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JM O. Multi-component polymers containing polylactic acid. Huang PSJ, ed. Storrs, Connecticut, USA: University of Connecticut, Institute of Materials Science, ; 1996.
JM K, CM M, JD M, J W. "A Retrospective Study of Canine Ehrlichiosis in Kenya." International Journal of Veterinary Science. 2014;3(33):122-124.mulei_c_2014_a_retrospective_study_of_canine_ehrlichiosis_in_kenya.pdf
JM K, JK K, AO W, Q Z. "Impact of pregnancy related acute kidney injury on feotal survival: a single centre experience in Kenya." IOSR Journal of Dental and Medical Sciences (IOSR-JDMS). 2019;18(7):13-17. Abstract

Background: Pregnancy related acute kidney injury (PRAKI) is a heterogenous obstetric
complication, which can occur at any stage during pregnancy and in postpartumperiod. It often impacts
negatively on foetaloutcomes.
Objective: To determine impact of PRAKI on foetal outcomes at Kenyatta National Hospital (KNH), Nairobi.
Methods: We carried out a descriptive study on women with viable pregnancies, gestation age equal to, or
above 28 weeks and postpartum women within six weeks after delivery admitted in labour ward or the postnatal wards at KNH. The study started afterit was approved by the KNH- University of Nairobi Ethics and
Research Committee.Patient management was at the discretion of attending clinician.Data was obtained
fromthe participants and their medical records. Followupwas until dischargeor for a maximum of two weeksfor
those who remained in the wards.
Results: Total participantswere 66 out of2068 admissions. Their mean age was 28years with peak age between
26-30 years.The prevalence of PRAKI was 3.2%. Sixty (91%) participants weredelivered andsix pregnancies
were ongoing past the follow-up period.The average gestation age at birth was 35 weeks. Forty-three (71.7%)
were life infants while 17(28.3%) were fresh still births. Comparing between participant women with PRAKI
and women without PRAKI, the ratio of fresh still births among participants was 1:4 and the ratio of fresh still
births among women without PRAKI was 1 in 23deliveries.
Conclusion: Wetherefore demonstrate that pregnancy related acute kidney injury was associated with a six (6)
fold increase in fresh still births at Kenyatta National Hospital in Kenya.
Key Words: PRAKI, KNH, Preterm births,Fresh still births,Nairobi, Kenya

JM O, Mulaa F, J M, P S. "Biodegradability of PLA, Preparation and Properties of PLA/Gum Blends." Journal of Polymers and the Environment. 2008;16:205-212.
JM, Kivai &, JK K, AO W, Q Z. "Maternal characteristics of women with pregnancy related acute kidney injury at Kenyatta National hospital, Kenya." IOSR Journal of Dental and Medical Sciences. 2019;18(9):69-75. Abstract

Background: Pregnancy is a physiologic state that can becomplicated by pregnancy related acute
kidney injury (PRAKI)which may occur at any stage of pregnancy and in postpartum,in previously healthy
women.It is associated with variable obstetric outcomesoften with significant butpreventable foeto-maternal
morbidity and mortality.
Objective:To determine maternal characteristics of in-patients with PRAKI at Kenyatta National Hospital
(KNH), Nairobi, Kenya
Methods:We carried out a descriptive study on in-patient pregnant women with gestation age of 28 completed
weeks or more and postpartum women within six weeks after deliveryadmitted inlabour ward or the post-natal
wards at KNH. Study started after approval by the KNH- University of Nairobi Ethics and Research Committee.
Data was obtained from the patientthrough verbal interviews andfrom the medical records using a pretested
data capture form.The participants were followed up for a maximum of two weeks or until discharge. The
patient management wasleft at the discretion of attending clinician.
Results: We enrolled 66 (3.2%) participants out of 2068 admissions.The mean agewas 28(SD5.9)years with
peak age between 26-30 years.Forty-two were referred from other health facilities. Nineteen (27.8%) had prepregnancy medical conditions mainly cardiovascular and all participants developed obstetric complication(s).
Hypertensive disorders of pregnancy were the main associated factors. Sixty (91%) participants were delivered
within two weeks after enrollment. The average gestation age at delivery was 35 weeks.Twenty-one (35%) were
delivered through caesarian section.Live infants were 43(71.7%) and fresh still births were 17(28.3%). The
ratio of fresh still births among participantswas 1:4 while the ratio of fresh still births among women without
PRAKI was 1:23deliveries.
Conclusion and recommendations:This study demonstrated prevalence of pregnancy related acute kidney injury
was 3.2% at K.N.H. The main associated factors were hypertensive disorders of pregnancy. Participants with
PRAKI were characterized with increased premature deliveries and a six (6) fold increase in fresh still births.
There is need for screening, monitoring and close follow-up of women with hypertensive disorders in pregnancy
and related kidney complications.
Key Words: PRAKI, KNH,hypertensive disorders of pregnancy, still births,Kenya

JM N, HA O, AN W. "E-LEARNING READINESS ASSESSMENT MODEL IN KENYAS’ HIGHER EDUCATION INSTITUTIONS: A CASE STUDY OF UNIVERSITY OF NAIROBI." Nov. 201 4 . Vol. 5 , No. 6 ISSN 230 5 - 1493 International Journal of Scientific Knowledge. 2014;5(6):29-41. Abstractelearning_readiness__assessment_model_in_kenya.pdf

In order to benefit from eLearning, institutions should conduct considerable up -front analysis to assess their eLearning readiness. Studies show that there are numerous models that have been developed, however, they are used in developed counties whose eReadiness is high hence not applicable in developing
countries. This paper includes a model that has been developed to assess eLearning readiness of lecturers from institutions of higher learning in Kenya. It investigates the eLearning readiness of lecturers from the University of Nairobi, and the objective was to carry out a diagnostic eLearning readiness assessment of lecturers and determine the factors that influence eLearning readiness. The questionnaires were administered to the lecturers. The results obtained indicate that an overwhelming majority are ready. In addition, the study results show that there is no significant relationship between age, gender, and level of education on eLearning readiness.The study results indicate that technological readiness is the most
important factor followed by culture readiness. Most of the lecturers felt that more training on content development need to be conducted. In conclusion, the lecturers are ready for eLearning but the ICT infrastructure is not adequate enough to support the use of eLearning.

JM K, JK K, AO W, Q Z. "Foetal outcomes in women with pregnancy related acute kidney injury in a referral facility in Kenya. ." IOSR Journal of Dental and Medical Sciences (IOSR-JDMS). 2019;18(11):52-56. Abstract

Background: Pregnancy related acute kidney injury (PRAKI) is an obstetric complication,which can occur at
any stage of pregnancy and in postpartum,often associated with significant adverse foetaloutcomes.
Objective:To determine foetal outcomes among patients with PRAKI at Kenyatta National Hospital (KNH),
Kenya.
Methods:We carried out a descriptive study on pregnant women with gestation age equal or above 28 weeks
and postpartum women within six weeks after deliverywho were admitted in labour ward or the post-natal
wards at KNH. Study commenced following approval by the KNH- University of Nairobi Ethics and Research
Committee. Data was obtained from both the patient and the medical records. Participants were followed up
until discharge orfor a maximum of two weeks. Patient management was at the discretion of attending clinician.
Results: ATotalof 66participants with a mean age of 28years and peak age between 26-30 years were enrolled
into the study out of 2068 admissions. The prevalence of PRAKI was 3.2%. Sixty (91%) participants gave birth
during the follow-up period and sixremained pregnant pastthe two weeks after enrollment. Average gestation
age at delivery was 35 weeks. Life infant were 43(71.7%) and fresh still births were 17(28.3%). Preterm births
were the majority33(55%),of whom 23were life infants and 10 were fresh still births.Comparing between
participants and women without PRAKI, the ratio of fresh still births was 1:4 while the ratio of fresh still births
among women without PRAKI was 1:23deliveries.
Conclusion:We demonstrate anaverage gestation age of 35 weeks and a six (6) fold increase in fresh still births
among women with pregnancy related acute kidney injury at KNH.
Key Words: PRAKI, KNH, Gestation age, Fresh still births, Kenya

JM N, HA O. "E-LEARNING READINESS ASSESSMENT MODEL IN KENYAS’ HIGHER EDUCATION INSTITUTIONS: A CASE STUDY OF UNIVERSITY OF NAIROBI." International Journal of Scientific Knowledge. 2014;5(6):29-41. Abstractelearning_readiness__assessment_model_in_kenya.pdf

In order to benefit from eLearning, institutions should conduct considerable up -front analysis to assess their eLearning readiness. Studies show that there are numerous models that have been developed, however, they are used in developed counties whose eReadiness is high hence not applicable in developing
countries. This paper includes a model that has been developed to assess eLearning readiness of lecturers from institutions of higher learning in Kenya. It investigates the eLearning readiness of lecturers from the University of Nairobi, and the objective was to carry out a diagnostic eLearning readiness assessment of lecturers and determine the factors that influence eLearning readiness. The questionnaires were administered to the lecturers. The results obtained indicate that an overwhelming majority are ready. In addition, the study results show that there is no significant relationship between age, gender, and level of education on eLearning readiness.The study results indicate that technological readiness is the most
important factor followed by culture readiness. Most of the lecturers felt that more training on content development need to be conducted. In conclusion, the lecturers are ready for eLearning but the ICT infrastructure is not adequate enough to support the use of eLearning.

JM Schoorl, A Veldkamp, L Claessens, JR Wijbrans, Olago DO, Lievens C. "Late Quaternary lahars and lava dams: Fluvial responses of the Upper Tana River (Kenya)." Geomorphology. 2019;341:28-45. Abstractlate_quaternery.pdfWebsite

Abstract

Geomorphological and sedimentary records near the confluences of the Tana River and major tributaries draining the eastern slopes of Mt. Kenya and the Nyambeni Range, indicate impacts of Late Quaternary volcanic activity in their fluvial records. The main reconstructed event was triggered by a 366.9 ka basalt flow (40Ar/39Ar dated) which flowed along Kazita River from the Nyambeni Range blocking both Kazita River and Tana River near Kibuka Grand Falls, causing a temporary lake. Consequently, Tana River and Kazita River started to build volcanoclastic Gilbert type deltas. The preserved pro-delta sediments rich in trachytic pumice fragments display a mineralogical and age match with known Ithanguni trachytic tuffs, indicating delta build up right after a contemporary Ithanguni eruption. This trachytic eruption caused the deposition of lahars and fluvial volcaniclastic sediments in all river records draining the Eastern side of Mt. Kenya. The multiple lahars seem to be triggered by eruptions under glacial conditions (basalt age indicates MIS 10). The lava dammed lake was only short lived (estimated to have lasted only a few years to decades) and breached before a complete lake infill could occur. The current Kibuka Grand Falls can be viewed as the delayed incisional response of this lava dam breach, indicating that after >366.9 ka, Tana River is still responding and adjusting to this short-lived disruptive phase. The current Kazita River has re-incised adjacent to a MIS 4 basalt flow down into the crystalline Basement System rocks. The MIS 10 pre-volcanic sedimentary record indicates that more sediments were in the fluvial system during glacial conditions than during the interglacial conditions. An implication of our reconstruction is that the Late Quaternary fluvial record of Tana River is of only limited use to reconstruct uplift rates because reconstructed Quaternary incision rates are reflecting both volcanic disruptions as climate change trends of aridification and decreasing glaciation extents.

JM.Kivai, Kayima JK, Were AO, Q.Zahida. "Impact of Pregnancy Related Acute Kidney Injury on foetalsurvival: a single Centre Experience in Kenya." IOSR Journal of Dental and Medical Sciences (IOSR-JDMS). 2019;18(7):13-17. AbstractWebsite

Abstract: Background: Pregnancy related acute kidney injury (PRAKI) is a heterogenous obstetric
complication, which can occur at any stage during pregnancy and in postpartumperiod. It often impacts
negatively on foetaloutcomes.
Objective: To determine impact of PRAKI on foetal outcomes at Kenyatta National Hospital (KNH), Nairobi.
Methods: We carried out a descriptive study on women with viable pregnancies, gestation age equal to, or
above 28 weeks and postpartum women within six weeks after delivery admitted in labour ward or the postnatal
wards at KNH. The study started afterit was approved by the KNH- University of Nairobi Ethics and
Research Committee.Patient management was at the discretion of attending clinician.Data was obtained
fromthe participants and their medical records. Followupwas until dischargeor for a maximum of two weeksfor
those who remained in the wards.
Results: Total participantswere 66 out of2068 admissions. Their mean age was 28years with peak age between
26-30 years.The prevalence of PRAKI was 3.2%. Sixty (91%) participants weredelivered andsix pregnancies
were ongoing past the follow-up period.The average gestation age at birth was 35 weeks. Forty-three (71.7%)
were life infants while 17(28.3%) were fresh still births. Comparing between participant women with PRAKI
and women without PRAKI, the ratio of fresh still births among participants was 1:4 and the ratio of fresh still
births among women without PRAKI was 1 in 23deliveries.
Conclusion: Wetherefore demonstrate that pregnancy related acute kidney injury was associated with a six (6)
fold increase in fresh still births at Kenyatta National Hospital in Kenya.
Key Words: PRAKI, KNH, Preterm births,Fresh still births,Nairobi, Kenya

jmbogoh. "CUSTOMER EXPERIENCE TRANSFORMATION." Foresight Magazine. 2011;2(2):9-10.
JN R, J N, EA R, W J. "Comparative evaluation of direct Ziehl-Neelsen (ZN) smear and modified ZN against fluorescent technique in the detection of acid-alcohol fast bacilli in lymph node aspirates." East African Journal of Pathology. 2014;1:19-22. Abstractcomparative_evaluation_of_direct_ziehl-neelsen_zn_smear_and_modified_zn_against_fluorescent_technique_in_the_detection_of_acid-alcohol_fast_bacilli_in_lymph_node_aspirates.pdf

Background: Tuberculosis is a major public health problem in Kenya as well as other developing countries. Diagnosis of extra-pulmonary tuberculosis is a common challenge especially where direct Ziehl Neelsen (ZN) technique is employed.
Objective: This study was aimed to establish whether modification of ZN by use of 3.5% NaOCl-Xylene Floatation would improve the detection of acid-alcohol fast bacilli (AAFBs) from lymph node aspirates.
Design: This was a descriptive cross-sectional study.
Setting: Kenyatta National Hospital, Kenya.
Subjects: One hundred cases suspected of clinically having TB with lymphadenopathy referred for fine needle aspiration cytology (FNAC) in FNA Clinic at Kenyatta National Hospital.
Methodology: The study was approved by Kenyatta National Hospital/ University of Nairobi/ Ethics and Research Committee (KNH/UON/ERC) and informed consent sought from patients. Analysis was done using SPSS version 12.0 for Windows (SPSS Inc.). McNemar’s test was used to assess the level of significance for the two test procedures. Chi-square was used to assess for the heterogeneity of the association between the two study methods.
Results: Thirty (30%) of the specimens were positive with fluorescent microscopy, 17% were modified ZN positive while 6% were direct ZN positive. The sensitivity, specificity, positive and negative predictive values for the modified technique (3.5% NaOCl-Xylene Floatation) were 53.3%, 98.6%, 94.1%, and 83.1% respectively.
Conclusions: Liquefaction of the aspirated specimens with NaOCl followed by Xylene floatation significantly increased the yield of AAFBs. This finding is of great interest in developing countries where smear-negative for acid-alcohol fast bacilli (AAFBs) has become common.
Recommendation: Local settings should consider adopting use of modified ZN technique in order to increase the sensitivity and detection rate of AAFBs from lymph node aspirates.

JN R, A W, R W, CK B. "Evaluation of rapid diagnostic methods for the diagnosis of cryptococcal meningitis in HIV positive patients in a health facility, Nairobi-Kenya." East African Journal of Pathology. 2015;2:18-22. Abstractevaluation_of_rapid_diagnostic_methods_for_the_diagnosis_of_cryptococcal_meningitis_in_hiv_positive_patients_in_a_health_facility_nairobi-kenya.pdf

Background: Cryptococcal meningitis is a fatal opportunistic infection in immune-compromised patients. Lack of simple, affordable, rapid and specific methods for diagnosis in many government health facilities in Kenya has aggravated patients’ conditions.
Objective: This study was aimed at determining the performance of India ink (Microscopy), latex agglutination test (LAT) and enzyme immunoassay (EIA) in the diagnosis of cryptococcal meningitis in a Kenyan population.
Design: Laboratory based cross-sectional study.
Setting: A high-volume government health facility based in Nairobi.
Subjects: One hundred and thirteen CSF samples from HIV positive patients with signs and symptoms of cryptococcal meningitis sent to the laboratory for routine analysis.
Methodology: The study was approved by the KEMRI Scientific Committee/Ethics Review Committee and informed consent sought from the patients. The test for the agreement between the test methods and the gold standard (Culture) was calculated using the non-parametric McNemar’s test using SPSS version 17 (SPSS Inc., Chicago, IL) at 5% significant level.
Results: Twenty one point six percent of all samples tested positive on LAT while 9% were positive on microscopy, EIA and culture. The sensitivity, specificity, positive and negative predictive values for microscopy and EIA were: 90%, 99%, 90% and 99% respectively. By LAT, the values were: 100%, 86.1%, 41.7% and 100% respectively. Both EIA and microscopy had an agreement of 89% whereas that of LAT was 52.8% with the gold standard (C.S.F culture).
Conclusion: From the results of this study, it is evident that Latex Agglutination Test was the most sensitive among the study methods. Therefore, LAT is an appropriate diagnostic test but requires confirmatory testing. EIA could be an appropriate confirmatory test but is limited because it is not available in our setup. India ink though available is user-dependent, a major limitation. The use of test combinations did not increase the sensitivity of neither India ink nor enzyme immunoassay and is therefore not significant in the diagnostic work up for cryptococcal meningitis.
Recommendations: Local settings may consider frequent and unlimited use of LAT as a sensitive diagnostic tool for cryptococcal meningitis. It is also important to note that positive LAT tests are accompanied with a confirmatory test due to unfavourable specificities as evidenced from the research findings. In areas where cost is not a limitation, EIA may be used as a confirmatory test. Future research of comparing lateral flow immunoassay (LFA) and the current test methods using CSF in our hospital set up is warranted.

JO M, LU(1) W, Faxelid EA, PN C, AA O'any, EB. N. "Nurse-midwives' attitudes towards adolescent sexual and reproductive health needs in Kenya and Zambia." Reprod Health Matters. 2006 May;14(27):119-28.. 2006.dr.musandu.pdf
JO M, R W, J W, R O, C K, J M, E M. "Establishing adolescent friendly services and use of adolescent package of care to improve outcome of ALHIV at a rural health center.". In: 10th Annual HIV Prevention, Care & Treatment Consultative Forum, . Nairobi, Kenya; 2015.
JOAB PROFBWAYOJOB. "Eosinophilia and eosinophil helminthotoxoity in patients treated for Schistoma mansoni infections G. Kimani, C.N Chunge, A.E Buterworth, T. Kamau, Bwayo JJ, G.Gachuhi and M. Mugambi. Transactions of the Royal Society of Tropical Medicine and Hygiene 1991;.". In: Transactions of the Royal Society of Tropical Medicine and Hygiene 1991;85: 89-492. Asian Economic and Social Society; 1991. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Partner notification of pregnant women infected with syphilis in Nairobi, Kenya. Gichangi P, Fonck K, Sekande-Kigondu C, Ndinya-Achola J, Bwayo J, Kiragu D, Claeys P, Temmerman M. Int J STD AIDS. 2000 Apr;11(4):257-61.". In: Int J STD AIDS. 2000 Apr;11(4):257-61. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, M. DROTIDOJULIUS. "Traditional healers and the management of sexually transmitted diseases in Nairobi, Kenya. Kusimba J, Voeten HA, O'hara HB, Otido JM, Habbema JD, Ndinya-Achola JO, Bwayo JJ. Int J STD AIDS. 2003 Mar;14(3):197-201.". In: Int J STD AIDS. 2003 Mar;14(3):197-201. The Kenya Medical Association; 2003. Abstract
BACKGROUND: Health care-seeking behavior for sexually transmitted diseases (STDs) is important in STD/HIV control. GOAL: The goal of this study was to describe the proportion seeking care, patient delay, and choice of provider among men and women with STD-related complaints in Nairobi, Kenya. STUDY DESIGN: A population-based questionnaire was administered in 7 randomly selected clusters (small geographic areas covering approximately 150 households each). RESULTS: Of the 291 respondents reporting complaints, 20% of men versus 35% of women did not seek care, mainly because symptoms were not considered severe, symptoms had disappeared, or as a result of lack of money. Of those who sought care, women waited longer than men (41 vs. 16 days). Most men and women went to the private sector (72% and 57%, respectively), whereas the informal sector was rarely visited (13% and 16%, respectively). Relatively more women visited the government sector (28% vs. 15%). Because women were mostly monogamous, they did not relate their complaints to sexual intercourse, which hampered prompt care-seeking. CONCLUSION: Women should be convinced to seek care promptly, eg, through health education in communities.
JOAB PROFBWAYOJOB. "Studies of human immunodeficiency virus type 1 mucosal viral shedding and transmission in Kenya. Overbaugh J; Kreiss J; Poss M; Lewis P; Mostad S John G; Nduati R; Mbori-Ngacha D; Martin Jr H; Richardson B; Jackson S; Neilson J; Long EM; Panteleeff D; Wel.". In: Infect Dis. 1999 May;179 Suppl 3:S401-4. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Decreased incidence of sexually transmitted diseases among trucking company workers in Kenya: results of a behavioural risk-reduction programme. Jackson DJ; Rakwar JP; Richardson BA; Mandaliya K Chohan BH; Bwayo JJ; Ndinya-Achola JO; Martin HL Jr; Moses S.". In: AIDS. 1997 Jun;11(7):903-9. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB. "In vitro stimulation by Haemophilus ducreyi antigen of peripheral blood mononuclear cells from HIV-seronegative and HIV seropositive chancroid patients.Van Laer L, Vingerhoets, J, Vanham, G, estens L, Bwayo J.J, Otido J, Piot P, Roggen E.. J-Infect-Dis. 1.". In: J-Infect-Dis. 1996 Jun; 173(6): 1437-44. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "A human immunodeficiency virus 1 (HIV-1) clade A vaccine in clinical trials: stimulation of HIV-specific T-cell responses by DNA and recombinant modified vaccinia virus Ankara (MVA) vaccines in humans. Mwau M, Cebere I, Sutton J, Chikoti P, Winstone N, We.". In: J Gen Virol. 2004 Apr;85(Pt 4):911-9. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Acceptability of HIV vaccine trials in high-risk heterosexual cohorts in Mombasa, Kenya. Jackson DJ; Martin HL Jr; Bwayo JJ; Nyange PM Rakwar JP; Kashonga F; Mandaliya K; Ndinya-Achola JO; Kreiss JK. AIDS. 1995 Nov;9(11):1279-83.". In: AIDS. 1995 Nov;9(11):1279-83. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Vitamin A supplementation and human immunodeficiency virus type 1 shedding in women: results of a randomized clinical trial. J Infect Dis. Baeten JM, McClelland RS, Overbaugh J, Richardson BA, Emery S, Lavreys L, Mandaliya K, Bankson DD, Ndinya-Achola JO,.". In: Epub 2002 Mar 22. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, N MRMAINGIELIUD. "Gender differences in health care-seeking behavior for sexually transmitted diseases: a population-based study in Nairobi, Kenya. Voeten HA, O'hara HB, Kusimba J, Otido JM, Ndinya-Achola JO, Bwayo JJ, Varkevisser CM, Habbema JD. Sex Transm Dis. 2004 May;3.". In: Sex Transm Dis. 2004 May;31(5):265-72. Kisipan, M.L.; 2004. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

JOAB PROFBWAYOJOB. "Correlates of mother-to-child human immunodeficiency virus type 1 (HIV-1) transmission: association with maternal plasma HIV-1 RNA load, genital HIV-1 DNA shedding, and breast infections. John GC, Nduati RW, Mbori-Ngacha DA, Richardson BA, Panteleeff D, M.". In: J Infect Dis. 2001 Jan 15;183(2):206-212. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Effect of a syphilis control programme on pregnancy outcome in Nairobi, Kenya. Temmerman M, Gichangi P, Fonck K, Apers L, Claeys P, Van Renterghem L, Kiragu D, Karanja G, Ndinya-Achola J, Bwayo JJ. Sex Transm Infect. 2000 Apr;76(2):117-21.". In: Sex Transm Infect. 2000 Apr;76(2):117-21. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Association of Chlamydia trachomatis heat-shock protein 60 antibody and HLA class II DQ alleles Gaur LK, Peeling RW, Cheang M, Kimani J, Bwayo JJ, Plummer F, Brunham RC. Infect Dis 1999 Jul; 180(1): 234-7.". In: Infect Dis 1999 Jul; 180(1): 234-7. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Hormonal contraception, vitamin A deficiency, and other risk factors for shedding of HIV-1 infected cells from the cervix and vagina [see comments] Mostad SB; Overbaugh J; DeVange DM; Welch MJ; Chohan B; Mandaliya K; Nyange P; Martin HL Jr; Ndinya-Achola .". In: Lancet. 1997 Sep 27;350(9082):922-7. Asian Economic and Social Society; 1997. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB. "The epidemiology of Chlamydia trachomatis within a sexually transmitted diseases core group. Brunham-RC; Kimani-J; Bwayo JJ.; Maitha-G; Maclean-I; Yang-C; Shen-C; Roman-S; Nagelkerke-NJ; Cheang-M; Plummer-FA. J-Infect-Dis. 1996 Apr; 173(4): 950-6.". In: J-Infect-Dis. 1996 Apr; 173(4): 950-6. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Comparison of the decline in CD4 counts in HIV -1 seropositive female sex workers and women from the general population in Nairobi, Kenya. Journal of acquired Immune Deficiency Syndrome. Bwayo J.J, Nagelkerke NJD, Moses S, Embree J, Ngugi EN, Mwatha A, Ki.". In: J-Acquir-Immune-Defic-Syndr-Hum-Retrovirol. 1995 Dec 1; 10(4): 457-61. John Benjamins Publishing Company; 1995. Abstract

BACKGROUND: There is indirect evidence that HIV-1 exposure does not inevitably lead to persistent infection. Heterogeneity in susceptibility to infection could be due to protective immunity. The objective of this study was to find out whether in highly HIV-1-exposed populations some individuals are resistant to infection. METHODS: We did an observational cohort study of incident HIV-1 infection-among 424 initially HIV-1-seronegative prostitutes in Nairobi, Kenya, between 1985 and 1994. 239 women seroconverted to HIV-1 during the study period. Exponential, Weibull, and mixture survival models were used to examine the effect of the duration of follow-up on incidence of HIV-1 infection. The influence of the duration of exposure to HIV-1 through prostitution on seroconversion risk was examined by Cox proportional hazards modelling, with control for other known or suspected risk factors for incident HIV-1 infection. HIV-1 PCR with env, nef, and vif gene primers was done on 43 persistently seronegative prostitutes who remained seronegative after 3 or more years of follow-up. FINDINGS: Modelling of the time to HIV-1 seroconversion showed that the incidence of HIV-1 seroconversion decreased with increasing duration of exposure, which indicates that there is heterogeneity in HIV-1 susceptibility or acquired immunity to HIV-1. Each weighted year of exposure through prostitution resulted in a 1.2-fold reduction in HIV-1 seroconversion risk (hazard ratio 0.83 [95% CI 0.79-0.88], p < 0.0001). Analyses of epidemiological and laboratory data, show that persistent seronegativity is not explained by seronegative HIV-1 infection or by differences in risk factors for HIV-1 infection such as safer sexual behaviours or the incidence of other sexually transmitted infections. Interpretation: We conclude that a small proportion of highly exposed individuals, who may have natural protective immunity to HIV-1, are resistant to HIV-1. PIP: A cohort study conducted in 1985-94 among 424 prostitutes from Nairobi, Kenya, who were initially human immunodeficiency virus (HIV)-1 seronegative, tended to provide support for the observation that some individuals in highly exposed populations may be resistant to infection. During the 10-year study period, 239 of these women seroconverted. The overall HIV-1 incidence was 42/100 person-years. After the first 2 years of follow up, in which the majority of seroconversions occurred, HIV-1 prevalence reached a plateau and then began a steep decline. To determine whether the risk of HIV-1 infection declined over time as a result of the selection of resistance, incidence rates among women with less than 3 years' versus more than 3 years' duration of prostitution were compared for 1989-93. An increasing protective effect for each seronegative year of exposure was observed. The estimated cumulative protective effect for women practicing prostitution from 1984-93 and remaining seronegative, compared to women who entered prostitution in 1994, was over 100-fold. To rule out the possibility that the decrease in seroconversion with duration of exposure reflected differences in sexual behavior or immunity to sexually transmitted diseases that facilitate HIV transmission, Cox proportional hazards modelling was performed. The weighted duration of prostitution was independently associated with a decreased risk of seroconversion. Each weighted year of exposure resulted in a 1.2-fold decrease in risk. Women who seroconverted were more likely to report 1 or more regular partners and to use condoms with these partners than their counterparts who remained seronegative. Elucidation of the protective mechanisms and the factors mediating the development of immunity against HIV-1 could be important to HIV-1 vaccine research.

JOAB PROFBWAYOJOB, N MRMAINGIELIUD. "Gender differences in health care-seeking behavior for sexually transmitted diseases: a population-based study in Nairobi, Kenya. Voeten HA, O'hara HB, Kusimba J, Otido JM, Ndinya-Achola JO, Bwayo JJ, Varkevisser CM, Habbema JD. Sex Transm Dis. 2004 May;3.". In: Sex Transm Dis. 2004 May;31(5):265-72. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Disseminated Mycobacterium avium infection among HIV-infected patients in Kenya.Gilks-CF; Brindle-RJ; Mwachari-C; Batchelor-B;Bwayo JJ; Kimari-J; Arbeit-RD; von-Reyn-CF J-Acquir-Immune-Defic-Syndr-Hum-Retrovirol.1995 Feb 1; 8(2): 195-8.". In: J-Acquir-Immune-Defic-Syndr-Hum-Retrovirol.1995 Feb 1; 8(2): 195-8. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "A prospective study of hormonal contraceptive use and cervical shedding of herpes simplex virus in human immunodeficiency virus type 1-seropositive women. McClelland RS, Wang CC, Richardson BA, Corey L, Ashley RL, Mandaliya K, Ndinya-Achola J, Bwayo JJ, K.". In: J Infect Dis. 2002 Jun 15;185(12):1822-5. Epub 2002 May 31. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Human immunodeficiency virus infection among high-risk seronegative prostitutes in Nairobi.Willerford DM; Bwayo JJ; Hensel M; Emonyi W; Plummer FA; Ngugi EN; Nagelkerke N; Gallatin WM; Kreiss J. J Infect Dis. 1993 Jun;167(6):1414-7.". In: J Infect Dis. 1993 Jun;167(6):1414-7. Asian Economic and Social Society; 1993. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "The effect of treatment of vaginal infections on shedding of human immunodeficiency virus type 1. Wang CC, McClelland RS, Reilly M, Overbaugh J, Emery SR, Mandaliya K, Chohan B, Ndinya-Achola J, Bwayo JJ, Kreiss JK. Infect Dis. 2001 Apr 1;183(7):1017-22.". In: Infect Dis. 2001 Apr 1;183(7):1017-22. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Pattern of sexually transmitted diseases and risk factors among women attending an STD referral clinic in Nairobi, Kenya. Fonck K, Kidula N, Kirui P, Ndinya-Achola J, Bwayo J, Claeys P, Temmerman M. Sex Transm Dis. 2000 Aug;27(7):417-23.". In: Sex Transm Dis. 2000 Aug;27(7):417-23. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Cervical Shedding of cytomegalovirus in human immunodeficiency virus type 1 infected women.Mostad SB, Kreiss JK, Ryncarz AJ,Overbaugh J, Mandaliya K, Chohan B, Ndinya-Achola J, Bwayo JJ, Corey LJ, Med virol 1999 Dec; 59(4): 469-73.". In: Med virol 1999 Dec; 59(4): 469-73. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Mother-child class I HLA concordance increase perinatal human immunodeficiency virus type 1 transmission. MacDonald KS; Embree J; Njenga S; Nagelkerke NJ; Ngatia I; Mohammed Z; Barber BH; Ndinya-Achola J; Bwayo JJ; Plummer FA. J Infect Dis. 1998 Mar;177(3.". In: J Infect Dis. 1998 Mar;177(3):551-6. Asian Economic and Social Society; 1998. Abstract
To determine the effect of human immunodeficiency virus type 1 (HIV-1) infection upon pelvic inflammatory disease (PID), a laparoscopic study of acute PID was conducted in Nairobi, Kenya. Subjects underwent diagnostic laparoscopy, HIV-1 serology, and testing for sexually transmitted diseases. Of the 133 women with laparoscopically verified salpingitis, 52 (39%) were HIV-1-seropositive. Tubo-ovarian abscesses (TOA) were found in 33% of HIV-1-infected and 15% of HIV-1-uninfected women (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.5). Among seropositive women, TOA was found in 55% of those with CD4 cell percent <14% vs. 28% with CD4 cell percent>14% (OR 3.1, 95% CI 0.6-15.3). Neisseria gonorrhoeae was detected in 37 women (28%) and Chlamydia trachomatis in 12 (9%); neither was significantly related to HIV-1 seropositivity. Length of hospitalization was not affected by HIV-1 serostatus overall but was prolonged among HIV-1-infected women with CD4 cell percent <14%. Among patients with acute salpingitis, likelihood of TOA was related to HIV-1 infection and advanced immunosuppression. In general, HIV-1-seropositive women with acute salpingitis responded well to treatment.
JOAB PROFBWAYOJOB. "Urethral Trichomonas vaginalis infection and HIV-1 transmission. Jackson DJ; Rakwar JP; Bwayo JJ; Kreiss JK; Moses S. Lancet. 1997 Oct 11;350(9084):1076.". In: Lancet. 1997 Oct 11;350(9084):1076. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Resistance to HIV-1 infection among persistently seronegative prostitutes in Nairobi, Kenya [see comments]. Fowke KR; Nagelkerke NJ; Kimani J; Simonsen JN; Anzala AO; Bwayo JJ; MacDonald KS; Ngugi EN; Plummer FA. Comment in: Lancet 1997 Mar 1;349 (9052):6.". In: Lancet. 1996 Nov 16;348(9038):1347-51. John Benjamins Publishing Company; 1997. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB. "Shedding of human herpesvirus 8 in oral and genital secretions from HIV-1-seropositive and -seronegative Kenyan women. Taylor MM, Chohan B, Lavreys L, Hassan W, Huang ML, Corey L, Ashley Morrow R, Richardson BA, Mandaliya K, Ndinya-Achola J, Bwayo JJ, Kre.". In: J Infect Dis. 2004 Aug 1;190(3):484-8. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Immunological changes during pregnancy in HIV-1 seropositive women and seronegative controls in Kenya. Temmerman M, Bwayo J.J, Emonyi W, Ndinya-Achola JO, Nagelkerke JND, Piot P. AIDS. 1995 Sep; 9(9): 1057-60.". In: AIDS. 1995 Sep; 9(9): 1057-60. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Vitamin A deficiency and the acute phase response among HIV-1-infected and -uninfected women in Kenya. Baeten JM, McClelland RS, Richardson BA, Bankson DD, Lavreys L, Wener MH, Overbaugh J, Mandaliya K, Ndinya-Achola JO, Bwayo JJ, Kreiss JK. J Acquir Immu.". In: J Acquir Immune Defic Syndr. 2002 Oct 1;31(2):243-9. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Preparation for AIDS vaccine evaluation in Mombasa, Kenya: Establishment of seronegative cohorts of commercial sex workers and trucking company employees. Martin HL Jr; Jackson DJ; Mandaliya K; Bwayo JJ; Rakwar JP; Nyange P; Moses S; Ndinya-Achola JO; Hol.". In: AIDS Res Hum Retroviruses. 1994;10 Suppl 2:S235-7. Asian Economic and Social Society; 1994. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Vitamin A and risk of HIV-1 seroconversion among Kenyan men with genital ulcers. MacDonald KS, Malonza I, Chen DK, Nagelkerke NJ, Nasio JM, Ndinya-Achola J, Bwayo JJ, Sitar DS, Aoki FY, Plummer FA. AIDS. 2001 Mar 30;15(5):635-639.". In: AIDS. 2001 Mar 30;15(5):635-639. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Theileria parva. Isolation of acroschizonts from in vitro propagated parasitized bovine lymphoblastoid cells. Nyormoi O., Bwayo JJ. and Hirumi H. (1981). Experimental Parasitology 52: 303?311.". In: Experimental Parasitology 52: 303?311. Asian Economic and Social Society; 1981. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Cervical shedding of Herpes Simplex Virus in Human Immunodeficiency Virus-Infected Women: Effects of Hormonal Contraception, Pregnancy, and vitamin A Deficiency. Mostad SB, Kreiss JK, Rycarz AJ, Mandaliya K, chohan B, Ndinya-Achola J, Bwayo JJ, Corey L. J.". In: J Infect Diseases 2000 Jan; 181(1): 58-63. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Cytotoxic T cell responses to multiple conserved HIV epitopes in HIV-resistant prostitutes in Nairobi [see comments] Rowland-Jones SL; Dong T; Fowke KR; Kimani J; Krausa P; Newell H; Blanchard T; Ariyoshi K; Oyugi J; Ngugi E; Bwayo JJ; MacDonald KS; McMic.". In: J Clin Invest 1998 Nov 1;102(9):1643-4 . Asian Economic and Social Society; 1998. Abstract
To determine the effect of human immunodeficiency virus type 1 (HIV-1) infection upon pelvic inflammatory disease (PID), a laparoscopic study of acute PID was conducted in Nairobi, Kenya. Subjects underwent diagnostic laparoscopy, HIV-1 serology, and testing for sexually transmitted diseases. Of the 133 women with laparoscopically verified salpingitis, 52 (39%) were HIV-1-seropositive. Tubo-ovarian abscesses (TOA) were found in 33% of HIV-1-infected and 15% of HIV-1-uninfected women (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.5). Among seropositive women, TOA was found in 55% of those with CD4 cell percent <14% vs. 28% with CD4 cell percent>14% (OR 3.1, 95% CI 0.6-15.3). Neisseria gonorrhoeae was detected in 37 women (28%) and Chlamydia trachomatis in 12 (9%); neither was significantly related to HIV-1 seropositivity. Length of hospitalization was not affected by HIV-1 serostatus overall but was prolonged among HIV-1-infected women with CD4 cell percent <14%. Among patients with acute salpingitis, likelihood of TOA was related to HIV-1 infection and advanced immunosuppression. In general, HIV-1-seropositive women with acute salpingitis responded well to treatment.
JOAB PROFBWAYOJOB. "Recent transmission of tuberculosis in a cohort of HIV-1-infected female sex workers in Nairobi, Kenya. C.F. Gilks, P. Godfre-Fausset, B.I.F. Batchelor, J.C. Ojoo, S.J. Ojoo, R.J. Brindle, J. Paul, J. Kimari, M.C. Bruce, Bwayo JJ, F.A. Plummer and D.A. Wa.". In: AIDS 1997, 11:911-918. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Recombination following superinfection by HIV-1. Fang G, Weiser B, Kuiken C, Philpott SM, Rowland-Jones S, Plummer F, Kimani J, Shi B, Kaul R, Bwayo JJ, Anzala O, Burger H. AIDS. 2004 Jan 23;18(2):153-9.". In: AIDS. 2004 Jan 23;18(2):153-9. John Benjamins Publishing Company; 2004. Abstract
OBJECTIVE: To determine the prevalence of HCV infection and HCV/HIV co-infection among voluntary blood donors at the National Blood Transfusion Centre and clients at the Kenyatta National Hospital HIV-Voluntary Counseling and Testing (VCT) Centre. DESIGN: A prospective cross-sectional descriptive study. SETTING: Kenyatta National Hospital, a tertiary referral and teaching hospital and the National Blood Transfusion Services Centre, Nairobi. SUBJECTS: Volunteer blood donors and VCT attendants. RESULTS: The prevalence of HCV/HIV co-infection among 6154 blood donors in the NBTSC was very low, at 0.02. The HIV prevalence among the 353 KNH HIV-VCT clients was 9.3%, none of the clients tested positive for HCV. The incidence of risk factors in the persons with HCV and/or HIV infection(s) was low. CONCLUSION: The prevalence of HCV infection among pre-screened volunteer blood donors was low. However the current practice of screening all donated blood for HCV remains indispensable to prevent its transmission to blood recipients.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Construction of an infectious HIV type 1 molecular clone from an African patient with a subtype D/C Recombinant Virus. Shi B, Philpott SM, Weiser B, Kuiken C, Brunner C, Fang G, Fowke KR, Plummer FA, Rowland-Jones S, Bwayo JJ, Anzala AO, Kimani J, Kaul R,.". In: AIDS Res Hum Retroviruses. 2004 Sep;20(9):1015-8. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Rapid progression to disease in African sex workers with human immunodificiency virus type 1 infection. Anzala AO, Nagelkerke NJD, Bwayo J.J, Holton D, Moses S, Ngugi EN, Ndinya-Achola JO and Plummer FA. Journal of Infectious Diseases 1995; 171: 686-9.". In: Journal of Infectious Diseases 1995; 171: 686-9. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "The effect of rapid HIV-1 testing on uptake of perinatal HIV-1 interventions: a randomized clinical trial. Malonza IM, Richardson BA, Kreiss JK, Bwayo JJ, Stewart GC. AIDS. 2003 Jan 3;17(1):113-8.". In: AIDS. 2003 Jan 3;17(1):113-8. Asian Economic and Social Society; 2003. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Bancroftian filariasis in Kwale District of Kenya: I clinical and parasitological survey in an endemic community. Estambale BBA, Simonsen PE, Knight R, Bwayo JJ. Annals of Tropical Medicine 1994,88:145-151.". In: Annals of Tropical Medicine 1994,88:145-151. Asian Economic and Social Society; 1994. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "HIV and cervical cancer in Kenya. Gichangi P, De Vuyst H, Estambale B, Rogo K, Bwayo JJ, Temmerman M. Int J Gynaecol Obstet. 2002 Jan;76(1):55-63.". In: Int J Gynaecol Obstet. 2002 Jan;76(1):55-63. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Preliminary report on the prevalence of sexually transmitted diseases and human immunodeficiency virus infection among long distance truck drivers.Bwayo JJ,Mutere A.N.,Omari M.A., Jaoko W;Plummer F.A.,Kreiss J.K.,Kigondu C.S. (1990).Proceedings of tenth A.". In: Proceedings of tenth Annual Medical Scientific Conference, KEMRI/KETRI, Nairobi, Kenya. Asian Economic and Social Society; 1990. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Cervical shedding of herpes simplex virus in human immunodeficiency virus-infected women: effects of hormonal contraception, pregnancy, and vitamin A efficiency. Mostad SB, Kreiss JK, Ryncarz AJ, Mandaliya K, Chohan B, Ndinya-Achola J, Bwayo JJ, Corey L. .". In: J Infect Dis. 2000 Jan;181(1):58-63. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Subtypes of human immunodeficiency virus type 1 and disease stage among women in Nairobi, Kenya. Neilson JR; John GC; Carr JK; Lewis P; Kreiss JK; Jackson S; Nduati RW; Mbori-Ngacha D; Panteleeff DD; Bodrug S; Giachetti C; Bott MA; Richardson BA; Bwayo JJ.". In: J.Virol. 1999 May;73(5):4393-403. Asian Economic and Social Society; 1999. Abstract
OBJECTIVES: To monitor and analyse trends in HIV-1 seroprevalence among antenatal women in Nairobi, Kenya. DESIGN: Six sequential surveys were carried out among antenatal clinic attenders at four Nairobi City Council health centres between November 1991 and April 1997. METHODS: A total of 6828 women attending for first antenatal clinic visit were administered a standard questionnaire to obtain demographic information and were screened for HIV-1. RESULTS: HIV-1 seroprevalence rose from 12.1% in the first survey to 16.2% in the third, completed in October 1993. No rise was observed in subsequent surveys, and seroprevalence among women under the age of 20 declined after the third survey. Significant differences in seroprevalence (P < 0.001) were observed in all survey rounds between women who reported that their province of origin was Nyanza (22.4% overall), compared with those from other provinces in western Kenya (14.1%), and the eastern group of provinces (8.9%). The rise in HIV-1 seroprevalence observed between 1991 and 1993 was almost entirely attributable to the rising seroprevalence among women from Nyanza. There were considerable differences in HIV-1 seroprevalence among the four health centres, partly accounted for by differences in the proportion of clinic attenders from different provinces of origin, which also changed significantly over time. CONCLUSIONS: HIV-1 seroprevalence has stabilized in antenatal women attending these health centres in Nairobi, and may be declining among women in the youngest age group. This may reflect stabilization of HIV-1 incidence, but further observation is required. The levels of infection among Nairobi residents reflect the evolution of the HIV epidemic in their provinces of origin, and changing client composition influences HIV-1 seroprevalence at different clinics. HIV sentinel surveillance should be carried out at multiple sites in large urban centres to monitor accurately the evolution of the HIV epidemic and the impact of control efforts in reducing transmission.
JOAB PROFBWAYOJOB. "Isoniazid preventive therapy for tuberculosis in HIV-1-infected adults: results of a randomized controlled trial. M.P. Hawken, H.K. Meme, L.C. Elliot, J.M. Chakaya, J.S. Morris, W.A. Githu, E.S. Juma, J.A. Odhiambo, L.N. Thiong'o, J.N. Kimari, E.N. Ngugi,.". In: AIDS 1997; 11: 875-882. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB. "The epidemiology of Chlamydia trachomatis within a sexually transmitted diseases core group. Brunham RC; Kimani J; Bwayo JJ; Maitha G; Maclean I; Yang C; Shen C; Roman S; Nagelkerke NJ; Cheang M; Plummer FA. J Infect Dis. 1996 Apr;173(4):950-6.". In: J Infect Dis. 1996 Apr;173(4):950-6. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Impact of HIV infection on invasive cervical cancer in Kenyan women. Gichangi PB, Bwayo JJ, Estambale B, De Vuyst H, Ojwang S, Rogo K, Abwao H, Temmerman M. AIDS. 2003 Sep 5;17(13):1963-8.". In: AIDS. 2003 Sep 5;17(13):1963-8. Asian Economic and Social Society; 2003. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Comparison of the declines in CD4 counts in HIV-1-seropositive female sex workers and women from the general population in Nairobi, Kenya. Bwayo JJ; Nagelkerke NJ; Moses S; Embree J; Ngugi EN; Mwatha A; Kimani J; Anzala A; Choudhri S; Achola JO; et al. Ac.". In: Acquir Immune Defic Syndr Hum Retrovirol. 1995 Dec 1;10(4):457-61. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "The importance of core groups in the epidemiology and control of HIV-1 infection. Plummer FA; Nagelkerke NJ; Moses S;Ndinya-Achola JO;Bwayo JJ; Ngugi E. AIDS. 1991;5 Suppl 1:S169-76.". In: AIDS. 1991;5 Suppl 1:S169-76. Asian Economic and Social Society; 1991. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Effect of breastfeeding and formula feeding on transmission of HIV-1: a randomized clinical trial. Nduati R, John G, Mbori-Ngacha D, Richardson B, Overbaugh J, Mwatha A, Ndinya-Achola J, Bwayo J, Onyango FE, Hughes J, Kreiss J. JAMA. 2000 Mar 1;283(9):116.". In: Int J STD AIDS. 2000 Apr;11(4):257-61. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Broadly cross-reactive HIV-specific cytotoxic T-lymphocytes in highly exposed persistently seronegative donors. Rowland-Jones SL; Dong T; Dorrell L; Ogg G Hansasuta P; Krausa P; Kimani J; Sabally S; Ariyoshi K; Oyugi J; MacDonald KS; Bwayo JJ; Whittle H; .". In: Immunol Lett. 1999 Mar;66(1-3):9-14. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Antibody to chlamydial hsp60 predicts an increased risk for chlamydial pelvic inflammatory disease. Peeling RW; Kimani J; Plummer F; Maclean I; Cheang M; Bwayo JJ; Brunham RC. J Infect Dis. 1997 May;175(5):1153-8.". In: J Infect Dis. 1997 May;175(5):1153-8. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB. "Invasive pneumococcal disease in a cohort of predominantly HIV-1 infected female sex-workers in Nairobi, Kenya [see comments]. Gilks CF; Ojoo SA; Ojoo JC; Brindle RJ; Paul J; Batchelor BI; Kimari JN; Newnham R; Bwayo JJ; Plummer FA; et al. COMMENTS: Comme.". In: Lancet. 1996 Mar 16;347(9003):718-23. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Use of serum retinol-binding protein for prediction of vitamin A deficiency: effects of HIV-1 infection, protein malnutrition, and the acute phase response. Baeten JM, Richardson BA, Bankson DD, Wener MH, Kreiss JK, Lavreys L, Mandaliya K, Bwayo JJ, McCle.". In: Am J Clin Nutr. 2004 Feb;79(2):218-25. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "HIV-1 and immunological changes during pregnancy:a comparison between HIV-1-seropositive and HIV-1-seronegative women in Nairobi, Kenya. Temmerman M; Nagelkerke N; Bwayo JJ;Chomba EN;Ndinya-Achola J; Piot P. AIDS.1995 Sep;9(9):1057-60.". In: AIDS.1995 Sep;9(9):1057-60. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Vulnerability of women in an African setting: lessons for mother-to-child HIV transmission prevention programmes. Gaillard P, Melis R, Mwanyumba F, Claeys P, Muigai E, Mandaliya K, Bwayo JJ, Temmerman M. AIDS. 2002 Apr 12;16(6):937-9.". In: AIDS. 2002 Apr 12;16(6):937-9. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Beta-2 microglobulin as a marker of HIV disease status in Nairobi,Kenya.Garden GA;Moss GB;Emonyi W;Bwayo JJ;Velentgas P;Kreiss J.Int J STD AIDS.1993 Jan Feb;4(1):49-51.". In: Int J STD AIDS.1993 Jan Feb;4(1):49-51. Asian Economic and Social Society; 1993. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Baseline STD prevalence in a community intervention trial of the female condom in Kenya. Feldblum PJ, Kuyoh M, Omari M, Ryan KA, Bwayo JJ, Welsh M. Sex Transm Infect. 2000 Dec;76(6):454-6.". In: Sex Transm Infect. 2000 Dec;76(6):454-6. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Influence of HLA supertypes on susceptibility and resistance to human immunodeficiency virus type 1 infection. MacDonald KS, Fowke KR, Kimani J, Dunand VA, Nagelkerke NJ, Ball TB, Oyugi J, Njagi E, Gaur LK, Brunham RC, Wade J, Luscher MA, Krausa P, Rowlan.". In: J Infect Dis. 2000 May;181(5):1581-9. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "HIV-1 specific mucosal IgA in a cohort of HIV-1 resistant Kenyan sex workers. Kaul R, Trabattoni D, Bwayo JJ, Arienti D, Zagliani A, Mwkangi FM, Kariuki C, Ngugi EN, MacDonald KS, Ball TB, Clerici M, Plummer FA. AIDS. 1999 Jan 14;13(1):23-9.". In: AIDS. 1999 Jan 14;13(1):23-9. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Risk factors for genital ulceration in Kenyan sex workers. The role of human immuno-deficiency virus type I infection. Kaul R; Kimani J; Nagelkerke NJ; Plummer FA; Bwayo JJ; Brunham RC; Ngugi EN; Ronald A. Sex Transm Dis. 1997 Aug;24(7):387-92.". In: Sex Transm Dis. 1997 Aug;24(7):387-92. Asian Economic and Social Society; 1997. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB. "Bacteruria in a cohort of predominantly HIV-1 seropositive female commercial sex workers in Nairobi , Kenya. Ojoo J, Paul J, Batchelor B, Amir M, Kimari J, Mwachari C, Bwayo J.J, Plummer., FA Gachihi G, Waiyaki P, Gilks C. J-Infect. 1996 Jul; 33(1): 33-7.". In: J-Infect. 1996 Jul; 33(1): 33-7. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Breast feeding and immunity to intestinal infections.Kakai R,Bwayo J.J,Wamola I.A, Ndinya- Achola,Nagelkerke NJD,Anzala AO,Plummer FA.East African Medical Journal 1995;72:1.". In: East African Medical Journal 1995;72:1. John Benjamins Publishing Company; 1995. Abstract

BACKGROUND: There is indirect evidence that HIV-1 exposure does not inevitably lead to persistent infection. Heterogeneity in susceptibility to infection could be due to protective immunity. The objective of this study was to find out whether in highly HIV-1-exposed populations some individuals are resistant to infection. METHODS: We did an observational cohort study of incident HIV-1 infection-among 424 initially HIV-1-seronegative prostitutes in Nairobi, Kenya, between 1985 and 1994. 239 women seroconverted to HIV-1 during the study period. Exponential, Weibull, and mixture survival models were used to examine the effect of the duration of follow-up on incidence of HIV-1 infection. The influence of the duration of exposure to HIV-1 through prostitution on seroconversion risk was examined by Cox proportional hazards modelling, with control for other known or suspected risk factors for incident HIV-1 infection. HIV-1 PCR with env, nef, and vif gene primers was done on 43 persistently seronegative prostitutes who remained seronegative after 3 or more years of follow-up. FINDINGS: Modelling of the time to HIV-1 seroconversion showed that the incidence of HIV-1 seroconversion decreased with increasing duration of exposure, which indicates that there is heterogeneity in HIV-1 susceptibility or acquired immunity to HIV-1. Each weighted year of exposure through prostitution resulted in a 1.2-fold reduction in HIV-1 seroconversion risk (hazard ratio 0.83 [95% CI 0.79-0.88], p < 0.0001). Analyses of epidemiological and laboratory data, show that persistent seronegativity is not explained by seronegative HIV-1 infection or by differences in risk factors for HIV-1 infection such as safer sexual behaviours or the incidence of other sexually transmitted infections. Interpretation: We conclude that a small proportion of highly exposed individuals, who may have natural protective immunity to HIV-1, are resistant to HIV-1. PIP: A cohort study conducted in 1985-94 among 424 prostitutes from Nairobi, Kenya, who were initially human immunodeficiency virus (HIV)-1 seronegative, tended to provide support for the observation that some individuals in highly exposed populations may be resistant to infection. During the 10-year study period, 239 of these women seroconverted. The overall HIV-1 incidence was 42/100 person-years. After the first 2 years of follow up, in which the majority of seroconversions occurred, HIV-1 prevalence reached a plateau and then began a steep decline. To determine whether the risk of HIV-1 infection declined over time as a result of the selection of resistance, incidence rates among women with less than 3 years' versus more than 3 years' duration of prostitution were compared for 1989-93. An increasing protective effect for each seronegative year of exposure was observed. The estimated cumulative protective effect for women practicing prostitution from 1984-93 and remaining seronegative, compared to women who entered prostitution in 1994, was over 100-fold. To rule out the possibility that the decrease in seroconversion with duration of exposure reflected differences in sexual behavior or immunity to sexually transmitted diseases that facilitate HIV transmission, Cox proportional hazards modelling was performed. The weighted duration of prostitution was independently associated with a decreased risk of seroconversion. Each weighted year of exposure resulted in a 1.2-fold decrease in risk. Women who seroconverted were more likely to report 1 or more regular partners and to use condoms with these partners than their counterparts who remained seronegative. Elucidation of the protective mechanisms and the factors mediating the development of immunity against HIV-1 could be important to HIV-1 vaccine research.

JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Recombination following superinfection by HIV-1. Fang G, Weiser B, Kuiken C, Philpott SM, Rowland-Jones S, Plummer F, Kimani J, Shi B, Kaul R, Bwayo JJ, Anzala O, Burger H. AIDS. 2004 Jan 23;18(2):153-9.". In: AIDS. 2004 Jan 23;18(2):153-9. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Effect of human immunodeficiency virus on local immunity in children with diarrhoea. Kakai R; Bwayo JJ; Wamola IA; Ndinya-Achola JO Plummer FA. East Afr Med J. 1995 Nov;72(11):699-702.". In: East Afr Med J. 1995 Nov;72(11):699-702. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Reduced HIV risk-taking and low HIV incidence after enrollment and risk-reduction counseling in a sexually transmitted disease prevention trial in Nairobi, Kenya. Kaul R, Kimani J, Nagelkerke NJ, Fonck K, Keli F, MacDonald KS, Ronald AR, Plummer FA, Bwayo.". In: J Acquir Immune Defic Syndr. 2002 May 1;30(1):69-72. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Late seroconversion in HIV-resistant Nairobi prostitutes despite pre-existing HIV- specific CD8+ responses. Kaul R, Rowland-Jones SL, Kimani J, Dong T, Yang HB, Kiama P, Rostron T, Njagi E, Bwayo JJ, MacDonald KS, McMichael AJ, Plummer FA. J Clin Invest. .". In: J Clin Invest. 2001 Feb;107(3):341-9. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, N DRMBATIAPAUL, O. PROFANZALAAGGREY. "Acute sexually transmitted infections increase human immunodeficiency virus type 1 plasma viremia, increase plasma type 2 cytokines, and decrease CD4 cell counts. Anzala AO, Simonsen JN, Kimani J, Ball TB, Nagelkerke NJ, Rutherford J, Ngugi EN, Bwayo JJ, .". In: J Infect Dis. 2000 Aug;182(2):459-66. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Intracluster correlation of STD prevalence in a community intervention trial in KenyaFeldblum PJ, Chen-Mok M, Bwayo JJ, Omari M, Kuyoh M, Ryan KA. Lancet. 1999 Octo 16;354(9187): 1356-7.". In: Lancet. 1999 Octo 16;354(9187): 1356-7. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB OOKO. VALUE PREMIUM AND INDUSTRY TYPE: EVIDENCE FROM THE NAIROBI STOCK EXCHANGE. Nairobi: University of Nairobi; 2011. Abstractvalue_premium_and_industry_type_2.pdf

Investors will always want to invest in projects than can guarantee higher returns than others, holding risk constant. They therefore tend to employ strategies that will contribute to the realization of higher returns. One of the most frequently used strategies is value investing where investors purchase value stocks rather than growth stocks in order to be benefit from potential long term performance of value stocks in the form of superior average returns. In finance, the word value premium refers to the excess return expected as a result of investing in value stocks as opposed to growth stocks. This study sought to find out whether there exists a value premium at the NSE when stocks are sorted on the basis of book to market value, and whether
industry type plays a role in value premium. It’s indicative from the study that value stocks outperformed growth stocks for the period under study. This is consistent with other studies done in Kenya. Muhoro (2004) tested a value premium of 0.64 for the period 1999-2002 at the NSE and Ngigi (2006) also tested the existence of value premium at the NSE. The result of the test in this study , conducted at 0.05 confidence level is that there exist value premium at the NSE. When stocks are grouped according to industries, there still exists value premium. Industrial and allied sector have the highest value premium of 4.125 while agricultural sector have the lowest value premium of -1.162. Therefore for a value strategist at the NSE, industrial and allied sector stocks are the best to invest in while agricultural sector stocks are the worst to invest in. The findings are also consistent with findings from similar studies in other markets in the world. Previous studies show that for 60 plus years value has outperformed growth. The conclusion of this study is that there exists a value premium at the N.S.E when stocks are sorted on the basis of B/M ratio . However there exists no significant difference in value premium across industries. This implies industry type is not a significant determinant of value premium.

JOAB PROFBWAYOJOB. "Anti-HLA alloantibody is found in children but does not correlate with a lack of HIV type 1 transmission from infected mothers. Luscher MA; Choy G; Embree JE; Nagelkerke NJ; Bwayo JJ; Njenga S; Plummer FA; Barber BH; MacDonald KS. AIDS Res Hum Retroviruse.". In: AIDS Res Hum Retroviruses. 1998 Jan 20;14(2):99-107. Asian Economic and Social Society; 1998. Abstract
To determine the effect of human immunodeficiency virus type 1 (HIV-1) infection upon pelvic inflammatory disease (PID), a laparoscopic study of acute PID was conducted in Nairobi, Kenya. Subjects underwent diagnostic laparoscopy, HIV-1 serology, and testing for sexually transmitted diseases. Of the 133 women with laparoscopically verified salpingitis, 52 (39%) were HIV-1-seropositive. Tubo-ovarian abscesses (TOA) were found in 33% of HIV-1-infected and 15% of HIV-1-uninfected women (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.5). Among seropositive women, TOA was found in 55% of those with CD4 cell percent <14% vs. 28% with CD4 cell percent>14% (OR 3.1, 95% CI 0.6-15.3). Neisseria gonorrhoeae was detected in 37 women (28%) and Chlamydia trachomatis in 12 (9%); neither was significantly related to HIV-1 seropositivity. Length of hospitalization was not affected by HIV-1 serostatus overall but was prolonged among HIV-1-infected women with CD4 cell percent <14%. Among patients with acute salpingitis, likelihood of TOA was related to HIV-1 infection and advanced immunosuppression. In general, HIV-1-seropositive women with acute salpingitis responded well to treatment.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Resistance to HIV-1 infection among persistently seronegative prostitutes in Nairobi, Kenya [see comments]. Fowke KR; Nagelkerke NJ; Kimani J; Simonsen JN; Anzala AO; Bwayo JJ; MacDonald KS; Ngugi EN; Plummer FA. Comment in: Lancet 1997 Mar 1;349 (9052):6.". In: Lancet. 1996 Nov 16;348(9038):1347-51. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Rapid progression to disease in African sex workers with human immunodeficiency virus type 1 infection [see comments] [published erratum appears in J InfectDis1996 Jun; 173(6):1529] Anzala OA; Nagelkerke NJ; Bwayo J.; Holton D Moses S; Ngugi EN; Ndinya-Ac.". In: J Infect Dis. 1995 Mar;171(3):686-9. John Benjamins Publishing Company; 1996. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB. "Monthly antibiotic chemoprophylaxis and incidence of sexually transmitted infections and HIV-1 infection in Kenyan sex workers: a randomized controlled trial. Kaul R, Kimani J, Nagelkerke NJ, Fonck K, Ngugi EN, Keli F, MacDonald KS, Maclean IW, Bwayo JJ, .". In: JAMA. 2004 Jun 2;291(21):2555-62. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Breast feeding and immunity to intestinal infections.Kakai R,Bwayo J.J,Wamola I.A, Ndinya- Achola,Nagelkerke NJD,Anzala AO,Plummer FA.East African Medical Journal 1995;72:1.". In: East African Medical Journal 1995;72:1. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "HLA-A and HLA-B in Kenya, Africa: allele frequencies and identification of HLA-B*1567 and HLA-B*4426.Tissue Antigens. Luo M, Embree J, Ramdahin S, Ndinya-Achola J, Njenga S, Bwayo JJ, Pan S, Mao X, Cheang M, Stuart T, Brunham RC, Plummer FA. 2002 May;59(5.". In: Plummer FA. 2002 May;59(5):370-80. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Human immunodeficiency virus infection in long-distance truck drivers in east Africa. Bwayo JJ; Plummer F; Omari M; Mutere A; Moses S; Ndinya-Achola J; Velentgas P; Kreiss J, Arch Intern Med. 1994 Jun 27;154(12):1391-6.". In: Arch Intern Med. 1994 Jun 27;154(12):1391-6. Asian Economic and Social Society; 1994. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Sequence and peptide-binding motif for a variant of HLA-A*0214 (A*02142) in an HIV-1-resistant individual from the Nairobi Sex Worker cohort. Luscher MA, MacDonald KS, Bwayo JJ, Plummer FA, Barber BH. Nucleotide. Immunogenetics. 2001 Feb;53(1):10-4.". In: Immunogenetics. 2001 Feb;53(1):10-4. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Isoenzyme pattern of Theileria Parva infected bovine lymphoblastoid cells and purified Theileria Macroschizont. Proceeding International Conference on Theileria. Nyormoi O., Bwayo JJ. (1981). Current Topics in Veterinary Medicine and Animal Sciences, 14: .". In: Proceeding International Conference on Theileria. Asian Economic and Social Society; 1981. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Effects of human immunodeficiency virus 1 infection on microbial origina of pelvic inflammatory disease and on efficacy of ambulatory oral therapy Bukusi EA, Cohen CR, Stevens CE, Sinei S, Reilly M, Grieco V, Eschenbach DA, Holmes KK, Bwayo JJ, Ndinya-ach.". In: Am J Obstet gynecol. 1999 Dec; 181(6): 1374-81. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Cervical and vaginal shedding of human immunodeficiency virus type 1-infected cells throughout the menstrual cycle. Mostad SB; Jackson S; Overbaugh J; Reilly M Chohan B; Mandaliya K; Nyange P; Ndinya-Achola J; Bwayo JJ Kreiss JK. Infect Dis. 1998 Oct;178(.". In: Infect Dis. 1998 Oct;178(4):983-91. Asian Economic and Social Society; 1998. Abstract
To determine the effect of human immunodeficiency virus type 1 (HIV-1) infection upon pelvic inflammatory disease (PID), a laparoscopic study of acute PID was conducted in Nairobi, Kenya. Subjects underwent diagnostic laparoscopy, HIV-1 serology, and testing for sexually transmitted diseases. Of the 133 women with laparoscopically verified salpingitis, 52 (39%) were HIV-1-seropositive. Tubo-ovarian abscesses (TOA) were found in 33% of HIV-1-infected and 15% of HIV-1-uninfected women (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.5). Among seropositive women, TOA was found in 55% of those with CD4 cell percent <14% vs. 28% with CD4 cell percent>14% (OR 3.1, 95% CI 0.6-15.3). Neisseria gonorrhoeae was detected in 37 women (28%) and Chlamydia trachomatis in 12 (9%); neither was significantly related to HIV-1 seropositivity. Length of hospitalization was not affected by HIV-1 serostatus overall but was prolonged among HIV-1-infected women with CD4 cell percent <14%. Among patients with acute salpingitis, likelihood of TOA was related to HIV-1 infection and advanced immunosuppression. In general, HIV-1-seropositive women with acute salpingitis responded well to treatment.
JOAB PROFBWAYOJOB. "Pattern of bacterial infections and antimicrobials susceptibility at the Kenyatta National Hospital , Nairobi, Kenya 1997. Omari M.A, I.M Malonza, Bwayo JJ, A.N Mutere, E.M Murage, A.K Mwatha and J.O NDinya- Achola. East African Medical Journal 1997;74:.". In: East African Medical Journal 1997;74:. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, N DRMBATIAPAUL, O. PROFANZALAAGGREY. "Acute sexually transmitted infections increase human immunodeficiency virus type 1 plasma viremia, increase plasma type 2 cytokines, and decrease CD4 cell counts. Anzala AO, Simonsen JN, Kimani J, Ball TB, Nagelkerke NJ, Rutherford J, Ngugi EN, Bwayo JJ, .". In: J Infect Dis. 2000 Aug;182(2):459-66. John Benjamins Publishing Company; 2000. Abstract
OBJECTIVE: To determine the prevalence of HCV infection and HCV/HIV co-infection among voluntary blood donors at the National Blood Transfusion Centre and clients at the Kenyatta National Hospital HIV-Voluntary Counseling and Testing (VCT) Centre. DESIGN: A prospective cross-sectional descriptive study. SETTING: Kenyatta National Hospital, a tertiary referral and teaching hospital and the National Blood Transfusion Services Centre, Nairobi. SUBJECTS: Volunteer blood donors and VCT attendants. RESULTS: The prevalence of HCV/HIV co-infection among 6154 blood donors in the NBTSC was very low, at 0.02. The HIV prevalence among the 353 KNH HIV-VCT clients was 9.3%, none of the clients tested positive for HCV. The incidence of risk factors in the persons with HCV and/or HIV infection(s) was low. CONCLUSION: The prevalence of HCV infection among pre-screened volunteer blood donors was low. However the current practice of screening all donated blood for HCV remains indispensable to prevent its transmission to blood recipients.
JOAB PROFBWAYOJOB. "HIV-1 Env-specific cytotoxic T-lymphocyte responses in exposed, uninfected Kenyan sex workers: a prospective analysis. Kaul R, Rutherford J, Rowland-Jones SL, Kimani J, Onyango JI, Fowke K, MacDonald K, Bwayo JJ, McMichael AJ, Plummer FA. AIDS. 2004 Oct 2.". In: AIDS. 2004 Oct 21;18(15):2087-9. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Comparison of the decline in CD4 counts in HIV -1 seropositive female sex workers and women from the general population in Nairobi, Kenya. Journal of acquired Immune Deficiency Syndrome. Bwayo J.J, Nagelkerke NJD, Moses S, Embree J, Ngugi EN, Mwatha A, Ki.". In: J-Acquir-Immune-Defic-Syndr-Hum-Retrovirol. 1995 Dec 1; 10(4): 457-61. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB, N DRMBATIAPAUL, O. PROFANZALAAGGREY. "Acute sexually transmitted infections increase human immunodeficiency virus type 1 plasma viremia, increase plasma type 2 cytokines, and decrease CD4 cell counts. Anzala AO, Simonsen JN, Kimani J, Ball TB, Nagelkerke NJ, Rutherford J, Ngugi EN, Bwayo JJ, .". In: J Infect Dis. 2000 Aug;182(2):459-66. Elsevier; 2000. Abstract
Ethnopharmacological relevance: Traditional medicines play an important role in the management of chronically painful and debilitating joint conditions, particularly in the rural Africa. However, their potential use as sources of medicines has not been fully exploited. The present study was carried to find the medicinal plants traditionally used to manage chronic joint pains in Machakos and Makueni counties in Kenya. Materials and methods: To obtain this ethnobotanical information, 30 consenting traditional herbal med-ical practitioners were interviewed exclusively on medicinal plant use in the management of chronic joint pains, in a pre-planned workshop. Results and discussion: In this survey, a total of 37 plants belonging to 32 genera and 23 families were cited as being important for treatment of chronic joint pains. The most commonly cited plant species were Pavetta crassipes K. Schum, Strychnos henningsii Gilg., Carissa spinarum L., Fagaropsis hildebrandtii (Engl.) Milve-Redh. and Zanthoxylum chalybeum Engl. Acacia mellifera (Vahl) Benth., Amaranthus albus L., Balanites glabra Mildbr. & Schltr., Grewia fallax K. Schum., Lactuca capensis, Launaea cornuta (Oliv. & Hiern) O. Jeffrey, Lippia kituiensis Vatke, Pappea capensis Eckl. & Zeyh. and Pennisetum glaucum (L.) R. Br. are documented for the first time as being important in the management of chronic joint pains. Conclusions: The findings of this study show that a variety of medicinal plants are used in the management of chronic joint pains and the main mode of administration is oral. Keywords: Ethnobotanical survey; Medicinal plants; Chronic joint pains; Rheumatoid arthritis; Akamba; Machakos-Kenya
JOAB PROFBWAYOJOB. "Childcare practices of commercial sex workers. Chege MN, Kabiru EW, Mbithi JN, Bwayo East Afr Med J. 2002 Jul;79(7):382-9.". In: East Afr Med J. 2002 Jul;79(7):382-9. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Bancroftian filariasis in Kwale district of Kenya: II Humoral immune responses to filarial antigens in selected individuals from endemic community. Estambale BBA, Simonsen Vennervald BJ, Knight R, Bwayo JJ. Annals of Tropical Medicine 1994;88:153-161.". In: Annals of Tropical Medicine 1994;88:153-161. Asian Economic and Social Society; 1994. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Syphilis control during pregnancy: effectiveness and sustainability of a decentralized program. Fonck K, Claeys P, Bashir F, Bwayo J, Fransen L, Temmerman M. Am J Public Health. 2001 May;91(5):705-7.". In: Am J Public Health. 2001 May;91(5):705-7. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Seroprevalence of HIV antibodies, HBs Ag and Syphilis in Western Kenya. Omari M., Bwayo JJ., Ndinya?Achola J.O., Wanzala P. (1989). Proceeding of 9th Annual Scientific Conference of KEMRI and KETRI.". In: Proceeding of 9th Annual Scientific Conference of KEMRI and KETRI. Asian Economic and Social Society; 1989. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "HIV-1 Specific Mucosal CD8+ Lymphocyte Responses in the Cervix of HIV-1 resistant Prostitutes in Nairobi. Kaul R, Plummer FA, Kimani J, Dong T, Kiama P, Rostron T, Njagi E, MacDonald KS, Bwayo J J, McMicheal AJ, Rowland-Jones SL, J Immunol 2000 Feb 1 ;164.". In: J Infect Dis. 2000 Jan;181(1):58-63. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "HIV type 1 resistance in Kenyan sex workers is not associated with altered cellular susceptibility to HIV type 1 infection or enhanced beta-chemokine production. Fowke KR; Dong T; Rowland-Jones SL; Oyugi J Rutherford WJ; Kimani J; Krausa P; Bwayo JJ; Simo.". In: AIDS Res Hum Retroviruses. 1998 Nov 20;14(17):1521-30. Asian Economic and Social Society; 1998. Abstract
OBJECTIVES: To monitor and analyse trends in HIV-1 seroprevalence among antenatal women in Nairobi, Kenya. DESIGN: Six sequential surveys were carried out among antenatal clinic attenders at four Nairobi City Council health centres between November 1991 and April 1997. METHODS: A total of 6828 women attending for first antenatal clinic visit were administered a standard questionnaire to obtain demographic information and were screened for HIV-1. RESULTS: HIV-1 seroprevalence rose from 12.1% in the first survey to 16.2% in the third, completed in October 1993. No rise was observed in subsequent surveys, and seroprevalence among women under the age of 20 declined after the third survey. Significant differences in seroprevalence (P < 0.001) were observed in all survey rounds between women who reported that their province of origin was Nyanza (22.4% overall), compared with those from other provinces in western Kenya (14.1%), and the eastern group of provinces (8.9%). The rise in HIV-1 seroprevalence observed between 1991 and 1993 was almost entirely attributable to the rising seroprevalence among women from Nyanza. There were considerable differences in HIV-1 seroprevalence among the four health centres, partly accounted for by differences in the proportion of clinic attenders from different provinces of origin, which also changed significantly over time. CONCLUSIONS: HIV-1 seroprevalence has stabilized in antenatal women attending these health centres in Nairobi, and may be declining among women in the youngest age group. This may reflect stabilization of HIV-1 incidence, but further observation is required. The levels of infection among Nairobi residents reflect the evolution of the HIV epidemic in their provinces of origin, and changing client composition influences HIV-1 seroprevalence at different clinics. HIV sentinel surveillance should be carried out at multiple sites in large urban centres to monitor accurately the evolution of the HIV epidemic and the impact of control efforts in reducing transmission.
JOAB PROFBWAYOJOB. "Urethral Infection in a Workplace Population of East African Men: Evaluation Strategies for Screening and Management. D.J. Jackson, J.P. Rakwar, B. Chohan, K. Mandaliya, Bwayo J J , J.O. Ndinya-Achola, N.J. D. Nagelkerke, J.K. Kreiss, and S. Moses. Journa.". In: AIDS 1997; 11: 875-882. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Construction of an infectious HIV type 1 molecular clone from an African patient with a subtype D/C Recombinant Virus. Shi B, Philpott SM, Weiser B, Kuiken C, Brunner C, Fang G, Fowke KR, Plummer FA, Rowland-Jones S, Bwayo JJ, Anzala AO, Kimani J, Kaul R,.". In: AIDS Res Hum Retroviruses. 2004 Sep;20(9):1015-8. John Benjamins Publishing Company; 2004. Abstract
OBJECTIVE: To determine the prevalence of HCV infection and HCV/HIV co-infection among voluntary blood donors at the National Blood Transfusion Centre and clients at the Kenyatta National Hospital HIV-Voluntary Counseling and Testing (VCT) Centre. DESIGN: A prospective cross-sectional descriptive study. SETTING: Kenyatta National Hospital, a tertiary referral and teaching hospital and the National Blood Transfusion Services Centre, Nairobi. SUBJECTS: Volunteer blood donors and VCT attendants. RESULTS: The prevalence of HCV/HIV co-infection among 6154 blood donors in the NBTSC was very low, at 0.02. The HIV prevalence among the 353 KNH HIV-VCT clients was 9.3%, none of the clients tested positive for HCV. The incidence of risk factors in the persons with HCV and/or HIV infection(s) was low. CONCLUSION: The prevalence of HCV infection among pre-screened volunteer blood donors was low. However the current practice of screening all donated blood for HCV remains indispensable to prevent its transmission to blood recipients.
JOAB PROFBWAYOJOB. "Associations of Sexual Risk Taking Among Kenyan Female Sex Workers After Enrollment in an HIV-1 Prevention Trial. Yadav G, Saskin R, Ngugi E, Kimani J, Keli F, Fonck K, Macdonald KS, Bwayo JJ, Temmerman M, Moses S, Kaul R; The Kibera HIV Study Group. J Ac.". In: J Acquir Immune Defic Syndr. 2005 Mar 1;38(3):329-334. Asian Economic and Social Society; 2005. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Rapid progression to disease in African sex workers with human immunodeficiency virus type 1 infection [see comments] [published erratum appears in J InfectDis1996 Jun; 173(6):1529] Anzala OA; Nagelkerke NJ; Bwayo J.; Holton D Moses S; Ngugi EN; Ndinya-Ac.". In: J Infect Dis. 1995 Mar;171(3):686-9. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Quantitative ex vivo analysis of functional virus-specific CD8 T lymphocytes in the blood and genital tract of HIV-infected women. Kaul R, Thottingal P, Kimani J, Kiama P, Waigwa CW, Bwayo JJ, Plummer FA, Rowland-Jones SL. AIDS. 2003 May 23;17(8):1139-44.". In: AIDS. 2003 May 23;17(8):1139-44. Asian Economic and Social Society; 2003. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Risk factors for mother-to-child transmission of human immunodeficiency virus-1 infection. Temmerman M; Nyong'o AO; Bwayo JJ; Fransen K; Coppens M; Piot P, Am J Obstet Gynecol. 1995 Feb;172(2 Pt 1):700-5.". In: Am J Obstet Gynecol. 1995 Feb;172(2 Pt 1):700-5. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Long distance truck drivers. 2:Knowledge and attitudes concerning sexually transmitted diseases and sexual behaviour. Bwayo JJ; Mutere AN; Omari MA; Kreiss JK; Jaoko W; Sekkade-Kigondu C; Plummer FA. East Afr Med J. 1991 Sep;68(9):714-9.". In: East Afr Med J. 1991 Sep;68(9):714-9. Asian Economic and Social Society; 1991. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "HIV-1-specific mucosal CD8+ lymphocyte responses in the cervix of HIV-1-resistant prostitutes in Nairobi. Kaul R, Plummer FA, Kimani J, Dong T, Kiama P, Rostron T, Njagi E, MacDonald KS, Bwayo JJ, McMichael AJ, Rowland-Jones SL. J Immunol. 2000 Feb 1;164(.". In: J Immunol. 2000 Feb 1;164(3):1602-11. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Cofactors for the acquisition of HIV-1 AIDS among heterosexual men: prospective cohort study of trucking company workers in Kenya. Rakwar J; Lavreys L; Thompson ML; Jackson D; Bwayo JJ Hassanali S; Mandaliya K; Ndinya-Achola J; Kreiss J. 1999 Apr 1;13(5):.". In: Kreiss J. 1999 Apr 1;13(5):607-14. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Detection of HIV infection during window period using polyclonal. B-cell activation test [letter] Jehuda-Cohen T; Mumo JM; Bwayo JJ; Pezzella M. AIDS. 1997 Jan;11(1):124-5.". In: 1997 Jan;11(1):124-5. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB. "Bacteriuria in a cohort of predominantly HIV-1 seropositive female commercial sex workers in Nairobi, Kenya. Ojoo J; Paul J; Batchelor B; Amir M; Kimari J Mwachari C; Bwayo JJ; Plummer F; Gachihi G; Waiyaki P; Gilks C. J Infect. 1996 Jul;33(1):33-7.". In: J Infect. 1996 Jul;33(1):33-7. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Complementary and alternative medicine instruction in nursing curricula. Dutta AP, Dutta AP, Bwayo JJ, Xue Z, Akiyode O, Ayuk-Egbe P, Bernard D, Daftary MN, Clarke-Tasker V, J Natl Black Nurses Assoc. 2003 Dec;14(2):30-3.". In: J Natl Black Nurses Assoc. 2003 Dec;14(2):30-3. Asian Economic and Social Society; 2003. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Human immunodeficiency virus DNA in urethral secretions in men: association with gonococcal urethritis and CD4 cell depletion. Moss GB; Overbaugh J; Welch M; Reilly M; Bwayo JJ; Plummer FA; Ndinya-Achola JO; Malisa MA; Kreiss JK. J Infect Dis. 1995 Dec;17.". In: J Infect Dis. 1995 Dec;172(6):1469-74. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Association between Mycoplasma genitalium and acute endometritis. Cohen CR, Manhart LE, Bukusi EA, Astete S, Brunham RC, Holmes KK, Sinei SK, Bwayo JJ, Totten PA. Lancet. 2002 Mar 2;359(9308):765-6.". In: Lancet. 2002 Mar 2;359(9308):765-6. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Multiple sexually acquired diseases occurring concurrently in an HIV positive man: case report, diagnosis and management. Oduor DO; Bwayo JJ; Bhatt SM; Kwasa TO; Maitha GM; Ombette JO. East African Medical Journal. 1992 Jun;69(6):345-6.". In: East African Medical Journal. 1992 Jun;69(6):345-6. Asian Economic and Social Society; 1992. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "A randomized, placebo-controlled trial of monthly azithromycin prophylaxis to prevent sexually transmitted infections and HIV-1 in Kenyan sex workers: study design and baseline findings. Fonck K, Kaul R, Kimani J, Keli F, MacDonald KS, Ronald AR, Plummer .". In: Int J STD AIDS. 2000 Dec;11(12):804-11. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Validity of the vaginal discharge algorithm among pregnant and non-pregnant women in Nairobi, Kenya. Fonck K, Kidula N, Jaoko W, Estambale B, Claeys P, Ndinya-Achola J, Kirui P, Bwayo J, Temmerman M. Sex Transm Infect. 2000 Feb;76(1):33-8.". In: Sex Transm Infect. 2000 Feb;76(1):33-8. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Increased interleukin-10 in the endocervical secretions of women with non-ulcerative sexually transmitted diseases: a mechanism for enhanced HIV-1 transmission? Cohen CR, Plummer FA, Mugo N, Maclean I, Shen C, Bukusi EA, Irungu E, Sinei S, Bwayo JJ, Brunh.". In: AIDS. 1999 Feb 25;13(3):327-32. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Antibody to Haemophilus ducreyi among trucking company workers in Kenya. Rakwar J; Jackson D; Maclean I; Obongo T; Bwayo JJ; Smith H; Mandaliya K; Moses S; Ndinya-Achola J; Kreiss JK. Sex Transm Dis. 1997 May;24(5):267-71.". In: Sex Transm Dis. 1997 May;24(5):267-71. Asian Economic and Social Society; 1997. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB. "Susceptibility to Chlamydia trochamatis pelvic inflammatory disease: relationship Brunham RC, Kimani J, Maclean IW, Bwayo J.J, Maitha GM, Nagelkerke NJD, Plummer FA. J-Infect-Dis. 1996 Jun; 173(6): 1437-44.". In: J-Infect-Dis. 1996 Jun; 173(6): 1437-44. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Low dose erythromycin regimen for the treatment of chancroid. Kimani J; Bwayo JJ; Anzala AO; MacLean I; Mwatha A; Choudri SH; Plummer FA; Ronald AR. East Afr Med J. 1995 Oct;72(10):645-8.". In: East Afr Med J. 1995 Oct;72(10):645-8. John Benjamins Publishing Company; 1995. Abstract

BACKGROUND: There is indirect evidence that HIV-1 exposure does not inevitably lead to persistent infection. Heterogeneity in susceptibility to infection could be due to protective immunity. The objective of this study was to find out whether in highly HIV-1-exposed populations some individuals are resistant to infection. METHODS: We did an observational cohort study of incident HIV-1 infection-among 424 initially HIV-1-seronegative prostitutes in Nairobi, Kenya, between 1985 and 1994. 239 women seroconverted to HIV-1 during the study period. Exponential, Weibull, and mixture survival models were used to examine the effect of the duration of follow-up on incidence of HIV-1 infection. The influence of the duration of exposure to HIV-1 through prostitution on seroconversion risk was examined by Cox proportional hazards modelling, with control for other known or suspected risk factors for incident HIV-1 infection. HIV-1 PCR with env, nef, and vif gene primers was done on 43 persistently seronegative prostitutes who remained seronegative after 3 or more years of follow-up. FINDINGS: Modelling of the time to HIV-1 seroconversion showed that the incidence of HIV-1 seroconversion decreased with increasing duration of exposure, which indicates that there is heterogeneity in HIV-1 susceptibility or acquired immunity to HIV-1. Each weighted year of exposure through prostitution resulted in a 1.2-fold reduction in HIV-1 seroconversion risk (hazard ratio 0.83 [95% CI 0.79-0.88], p < 0.0001). Analyses of epidemiological and laboratory data, show that persistent seronegativity is not explained by seronegative HIV-1 infection or by differences in risk factors for HIV-1 infection such as safer sexual behaviours or the incidence of other sexually transmitted infections. Interpretation: We conclude that a small proportion of highly exposed individuals, who may have natural protective immunity to HIV-1, are resistant to HIV-1. PIP: A cohort study conducted in 1985-94 among 424 prostitutes from Nairobi, Kenya, who were initially human immunodeficiency virus (HIV)-1 seronegative, tended to provide support for the observation that some individuals in highly exposed populations may be resistant to infection. During the 10-year study period, 239 of these women seroconverted. The overall HIV-1 incidence was 42/100 person-years. After the first 2 years of follow up, in which the majority of seroconversions occurred, HIV-1 prevalence reached a plateau and then began a steep decline. To determine whether the risk of HIV-1 infection declined over time as a result of the selection of resistance, incidence rates among women with less than 3 years' versus more than 3 years' duration of prostitution were compared for 1989-93. An increasing protective effect for each seronegative year of exposure was observed. The estimated cumulative protective effect for women practicing prostitution from 1984-93 and remaining seronegative, compared to women who entered prostitution in 1994, was over 100-fold. To rule out the possibility that the decrease in seroconversion with duration of exposure reflected differences in sexual behavior or immunity to sexually transmitted diseases that facilitate HIV transmission, Cox proportional hazards modelling was performed. The weighted duration of prostitution was independently associated with a decreased risk of seroconversion. Each weighted year of exposure resulted in a 1.2-fold decrease in risk. Women who seroconverted were more likely to report 1 or more regular partners and to use condoms with these partners than their counterparts who remained seronegative. Elucidation of the protective mechanisms and the factors mediating the development of immunity against HIV-1 could be important to HIV-1 vaccine research.

JOAB PROFBWAYOJOB. "Vitamin A supplementation and genital shedding of herpes simplex virus among HIV-1-infected women: a randomized clinical trial. Baeten JM, McClelland RS, Corey L, Overbaugh J, Lavreys L, Richardson BA, Wald A, Mandaliya K, Bwayo JJ, Kreiss JK. J Infect Di.". In: J Infect Dis. 2004 Apr 15;189(8):1466-71. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Low dose erythromycin regimen for the treatment of chancroid. Kimani J; Bwayo JJ; Anzala AO; MacLean I; Mwatha A; Choudri SH; Plummer FA; Ronald AR. East Afr Med J. 1995 Oct;72(10):645-8.". In: East Afr Med J. 1995 Oct;72(10):645-8. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Gonococcal cervicitis is associated with reduced systemic CD8+ T cell responses in human immunodeficiency virus type 1-infected and exposed, uninfected sex workers. Kaul R, Rowland-Jones SL, Gillespie G, Kimani J, Dong T, Kiama P, Simonsen JN, Bwayo JJ, M.". In: J Infect Dis. 2002 May 15;185(10):1525-9. Epub 2002 Apr 30. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Urine proves a poor specimen for culture of Trichomonas vaginalis in women. Mohamed OA, Cohen CR, Kungu D, Kuyoh MA, Onyango JA, Bwayo JJ, Welsh M, Feldblum PJ. Sex Transm Infect. 2001 Feb;77(1):78-9.". In: Sex Transm Infect. 2001 Feb;77(1):78-9. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Evaluation of performance of the Gen-Probe human immunodeficiency virus type 1 viral load assay using primary subtype A, C, and D isolates from Kenya. Emery S, Bodrug S, Richardson BA, Giachetti C, Bott MA, Panteleeff D, Jagodzinski LL, Michael NL, Nduati.". In: J Clin Microbiol. 2000 Jul;38(7):2688-95. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Effect of circumcision on incidence of human immunodeficiency virus type 1 and other sexually transmitted diseases: a prospective cohort study of trucking company employees in Kenya. Lavreys L, Rakwar JP, thompson ML, Jackson DJ, Mandaliya K, Chohan B, Bw.". In: J Infect Dis,. 1999 Jul; 180(2): 330-6. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Luscher MA, Choy G, Njagi E, Bwayo JJ, Anzala AO, Ndinya-Achola JO, Ball TB, Wade JA, Plummer FA, Barber BH, MacDonald KS.Naturally occurring IgG anti-HLA alloantibody does not correlate with HIV type 1 resistance in Nairobi prostitutes.AIDS Res Hum Retro.". In: AIDS Res Hum Retroviruses. 1998 Jan 20;14(2):109-15. Asian Economic and Social Society; 1998. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB. "Increased risk of infection with human immunodeficiency virus type 1 among uncircumcised men presenting with genital ulcer disease in Kenya. Tyndall-MW; Ronald AR; Agoki-E; Malisa-W; Bwayo JJ; Ndinya-Achola-JO; Moses-S; Plummer-FA. Clin-Infect-Dis. 1996 S.". In: Clin-Infect-Dis. 1996 Sep; 23(3): 449-53. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Rapid progression to disease in African sex workers with human immunodificiency virus type 1 infection. Anzala AO, Nagelkerke NJD, Bwayo J.J, Holton D, Moses S, Ngugi EN, Ndinya-Achola JO and Plummer FA. Journal of Infectious Diseases 1995; 171: 686-9.". In: Journal of Infectious Diseases 1995; 171: 686-9. John Benjamins Publishing Company; 1995. Abstract

BACKGROUND: There is indirect evidence that HIV-1 exposure does not inevitably lead to persistent infection. Heterogeneity in susceptibility to infection could be due to protective immunity. The objective of this study was to find out whether in highly HIV-1-exposed populations some individuals are resistant to infection. METHODS: We did an observational cohort study of incident HIV-1 infection-among 424 initially HIV-1-seronegative prostitutes in Nairobi, Kenya, between 1985 and 1994. 239 women seroconverted to HIV-1 during the study period. Exponential, Weibull, and mixture survival models were used to examine the effect of the duration of follow-up on incidence of HIV-1 infection. The influence of the duration of exposure to HIV-1 through prostitution on seroconversion risk was examined by Cox proportional hazards modelling, with control for other known or suspected risk factors for incident HIV-1 infection. HIV-1 PCR with env, nef, and vif gene primers was done on 43 persistently seronegative prostitutes who remained seronegative after 3 or more years of follow-up. FINDINGS: Modelling of the time to HIV-1 seroconversion showed that the incidence of HIV-1 seroconversion decreased with increasing duration of exposure, which indicates that there is heterogeneity in HIV-1 susceptibility or acquired immunity to HIV-1. Each weighted year of exposure through prostitution resulted in a 1.2-fold reduction in HIV-1 seroconversion risk (hazard ratio 0.83 [95% CI 0.79-0.88], p < 0.0001). Analyses of epidemiological and laboratory data, show that persistent seronegativity is not explained by seronegative HIV-1 infection or by differences in risk factors for HIV-1 infection such as safer sexual behaviours or the incidence of other sexually transmitted infections. Interpretation: We conclude that a small proportion of highly exposed individuals, who may have natural protective immunity to HIV-1, are resistant to HIV-1. PIP: A cohort study conducted in 1985-94 among 424 prostitutes from Nairobi, Kenya, who were initially human immunodeficiency virus (HIV)-1 seronegative, tended to provide support for the observation that some individuals in highly exposed populations may be resistant to infection. During the 10-year study period, 239 of these women seroconverted. The overall HIV-1 incidence was 42/100 person-years. After the first 2 years of follow up, in which the majority of seroconversions occurred, HIV-1 prevalence reached a plateau and then began a steep decline. To determine whether the risk of HIV-1 infection declined over time as a result of the selection of resistance, incidence rates among women with less than 3 years' versus more than 3 years' duration of prostitution were compared for 1989-93. An increasing protective effect for each seronegative year of exposure was observed. The estimated cumulative protective effect for women practicing prostitution from 1984-93 and remaining seronegative, compared to women who entered prostitution in 1994, was over 100-fold. To rule out the possibility that the decrease in seroconversion with duration of exposure reflected differences in sexual behavior or immunity to sexually transmitted diseases that facilitate HIV transmission, Cox proportional hazards modelling was performed. The weighted duration of prostitution was independently associated with a decreased risk of seroconversion. Each weighted year of exposure resulted in a 1.2-fold decrease in risk. Women who seroconverted were more likely to report 1 or more regular partners and to use condoms with these partners than their counterparts who remained seronegative. Elucidation of the protective mechanisms and the factors mediating the development of immunity against HIV-1 could be important to HIV-1 vaccine research.

JOAB PROFBWAYOJOB. "Human herpesvirus 8 seroconversion in Kenyan women by enzyme-linked immunosorbent assay and immunofluorescence assay. Chohan BH, Taylor H, Obrigewitch R, Lavreys L, Richardson BA, Mandaliya KN, Bwayo JJ, Kreiss JK, Morrow RA. J Clin Virol. 2004 Jun;30(2):.". In: J Clin Virol. 2004 Jun;30(2):137-44. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Low dose of erythromycin in the treatment of chancroi. Kimani J, Maclean I, Anzala A, Bwayo J.J. East-AfricanMedical Journal. 1995 Oct; 72(10): 645-8.". In: East-AfricanMedical Journal. 1995 Oct; 72(10): 645-8. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Cross-clade HIV-1-specific neutralizing IgA in mucosal and systemic compartments of HIV-1-exposed, persistently seronegative subjects. Devito C, Hinkula J, Kaul R, Kimani J, Kiama P, Lopalco L, Barass C, Piconi S, Trabattoni D, Bwayo JJ, Plummer F, Cleric.". In: J Acquir Immune Defic Syndr. 2002 Aug 1;30(4):413-20. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Human immunodeficiency virus infection among high risk seronegative prostitutes in Nairobi. Wilferford DM, Bwayo JJ, Hensel M, Emonyi W, Plummer FA, et al. Infectious Diseases 1993;167:141?7.". In: Infectious Diseases 1993;167:141?7. Asian Economic and Social Society; 1993. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Validation of a modified commercial enzyme-linked immunoassay for detection of human immunodeficiency virus type 1 immunoglobulin g antibodies in saliva. Chohan BH, Lavreys L, Mandaliya KN, Kreiss JK, Bwayo JJ, Ndinya-Achola JO, Martin HL Jr. Clin Diagn L.". In: Clin Diagn Lab Immunol. 2001 Mar;8(2):346-8. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Present status of in vitro cultivation of animal infective. African trypanosomes. In the in vitro cultivation of the Pathogens of Tropical Disease, Schwabe and Co., Hirumi H., Hirumi K., Nelson T.R. and Bwayo JJ. (1980). AC Basel. pp 163-200.". In: AC Basel. pp 163-200. Asian Economic and Social Society; 1980. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "The female condom and STDs: design of a community intervention trial. Feldblum PJ, Bwayo JJ, Kuyoh M, Welsh M, Ryan KA, Chen-Mok , M. Ann Epidemiol. 2000 Aug;10(6):339-46.". In: Epidemiol. 2000 Aug;10(6):339-46. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Vaginal lactobacilli, microbial flora, and risk of human immunodeficiency virus type 1 and sexually transmitted disease acquisition.Martin HL, richardson BA, Nyange PM, Lavreys L, Hillier SL, Chohan B, Mandaliya K, Ndinya-Achola JO, Bwayo JJ, Kreiss J. In.". In: Infect. Diseases 1999 Dec; (180(6): 1863-8. Asian Economic and Social Society; 1999. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Evolution of envelope sequences from the genital tract and peripheral blood of women infected with clade A human immunodeficiency virus type 1. Poss M; Rodrigo AG; Gosink JJ; Learn GH; de Vange Panteleeff D; Martin HL Jr; Bwayo JJ; Kreiss JK; Overbaugh J.". In: J Virol. 1998 Oct;72(10):8240-51. Asian Economic and Social Society; 1998. Abstract
To determine the effect of human immunodeficiency virus type 1 (HIV-1) infection upon pelvic inflammatory disease (PID), a laparoscopic study of acute PID was conducted in Nairobi, Kenya. Subjects underwent diagnostic laparoscopy, HIV-1 serology, and testing for sexually transmitted diseases. Of the 133 women with laparoscopically verified salpingitis, 52 (39%) were HIV-1-seropositive. Tubo-ovarian abscesses (TOA) were found in 33% of HIV-1-infected and 15% of HIV-1-uninfected women (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.5). Among seropositive women, TOA was found in 55% of those with CD4 cell percent <14% vs. 28% with CD4 cell percent>14% (OR 3.1, 95% CI 0.6-15.3). Neisseria gonorrhoeae was detected in 37 women (28%) and Chlamydia trachomatis in 12 (9%); neither was significantly related to HIV-1 seropositivity. Length of hospitalization was not affected by HIV-1 serostatus overall but was prolonged among HIV-1-infected women with CD4 cell percent <14%. Among patients with acute salpingitis, likelihood of TOA was related to HIV-1 infection and advanced immunosuppression. In general, HIV-1-seropositive women with acute salpingitis responded well to treatment.
JOAB PROFBWAYOJOB. "Hormonal contraception, vitamin A deficiency, and other risk factors for shedding of HIV-1 infected cells from the cervix and vagina. Mostad-SB; Overbaugh-J; DeVange-DM; Welch-MJ; Chohan-B; Mandaliya-K; Nyange-P; Martin-HL Jr; Ndinya-Achola-J; Bwayo JJ.; .". In: Lancet. 1997 Sep 27; 350(9082): 922-7. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Luscher MA, Choy G, Njagi E, Bwayo JJ, Anzala AO, Ndinya-Achola JO, Ball TB, Wade JA, Plummer FA, Barber BH, MacDonald KS.Naturally occurring IgG anti-HLA alloantibody does not correlate with HIV type 1 resistance in Nairobi prostitutes.AIDS Res Hum Retro.". In: AIDS Res Hum Retroviruses. 1998 Jan 20;14(2):109-15. John Benjamins Publishing Company; 1998. Abstract
In an effort to identify an immunological basis for natural resistance to HIV-1 infection, we have examined serum antibody responses to HLA class I antigens in female prostitutes of the Nairobi Sex Workers Study. Anti-HLA antibodies are known to block HIV infectivity in vitro and can be protective against SIV challenge in macaques immunized with purified class I HLA. Thus, it was postulated that broadly cross-reactive alloantibodies recognizing common HLA alleles in the client population might contribute to the prevention of heterosexual transmission of HIV. In fact, 12% of the women were found to have serum IgG antibodies against class I alloantigens. However, this alloantibody did not correlate with the HIV status of the women and was found in a similar proportion of HIV-positive and HIV-resistant women. The observed levels of alloantibody did not increase with HIV infection in susceptible individuals, suggesting that potential antigenic mimicry between HIV and host HLA class I antigens does not significantly increase levels of anti-class I antibodies. The lack of correlation between serum anti-allo-class I HLA antibodies and the risk of sexual transmission indicates that this humoral immune response is unlikely to be the natural mechanism behind the HIV-resistance phenotype of persistently HIV-seronegative women. This result, however, does not preclude the further investigation of alloimmunization as an artificial HIV immunization strategy.
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Long-term survivors in Nairobi: complete HIV-1 RNA sequences and immunogenetic associations. Fang G, Kuiken C, Weiser B, Rowland-Jones S, Plummer F, Chen CH, Kaul R, Anzala AO, Bwayo JJ, Kimani J, Philpott SM, Kitchen C, Sinsheimer JS, Gaschen B, Lang D, .". In: Burger HJ Infect Dis. 2004 Aug 15;190(4):697-701. Asian Economic and Social Society; 2004. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Human immunodeficiency virus in urethral secretions in men:Associations with gonococcal urethritis and CD4 depletion.Moss GB, Overbaugh J, Welch M, Relly M, Bwayo J.J, Plummer FA, Ndinya-Achola JO, Melisa MA, Kreiss JK. Journal of Infectious Disease 1995;.". In: Journal of Infectious Disease 1995;172:1469-74. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Association between cervical shedding of herpes simplex virus and HIV-1. McClelland RS, Wang CC, Overbaugh J, Richardson BA, Corey L, Ashley RL, Mandaliya K, Ndinya-Achola J, Bwayo JJ, Kreiss JK. AIDS. 2002 Dec 6;16(18):2425-30.". In: AIDS. 2002 Dec 6;16(18):2425-30. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Human Immunodificiency Virus infection in long-distance truck drivers in East Africa. Bwayo JJ, Plummer FA, Omari MA, Mutere A, Mosses S, Ndinya-Achola JO, Velengtgas P, Kreiss JK. Archives of Internal Medicine 1994;154:1391-1396.". In: Archives of Internal Medicine 1994;154:1391-1396. Asian Economic and Social Society; 1994. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Lymphocyte subsets in human immunodeficiency virus type 1-infected and uninfected children in Nairobi. Embree J, Bwayo J, Nagelkerke N, Njenga S, Nyange P, Ndinya-Achola J, Pamba H, Plummer F.Pediatr Infect Dis J. 2001 Apr;20(4):397-403.". In: Pediatr Infect Dis J. 2001 Apr;20(4):397-403. Asian Economic and Social Society; 2001. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Isopycnic Isolation of African Trypanosomes on Percoll gradients formed in situ. Grab DJ. Bwayo JJ. (1982). Acta Topics, 39: 363?366.". In: Acta Topics, 39: 363?366. Asian Economic and Social Society; 1982. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Human leucocyte antigen class II DQ alleles associated with Chlamydia trachomatis tubal infertility. Cohen CR, Sinei SS, Bukusi EA, Bwayo JJ, Holmes KK, Brunham RC. Obstet Gynecol,. 2000 Jan (1): 72-7.". In: Obstet Gynecol,. 2000 Jan (1): 72-7. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Cohen CR; Sinei S; Reilly M; Bukusi E; Eschenbach D; Holmes KK; Ndinya-Achola JO; Bwayo JJ; Grieco V; Stamm W; Karanja J; Kreiss J.Effect of human immunodeficiency virus type 1 infection upon acute salpingitis: a laparoscopic study.Infect Dis. 1998 Nov;17.". In: Infect Dis. 1998 Nov;178(5):1352-8. Asian Economic and Social Society; 1998. Abstract
To determine the effect of human immunodeficiency virus type 1 (HIV-1) infection upon pelvic inflammatory disease (PID), a laparoscopic study of acute PID was conducted in Nairobi, Kenya. Subjects underwent diagnostic laparoscopy, HIV-1 serology, and testing for sexually transmitted diseases. Of the 133 women with laparoscopically verified salpingitis, 52 (39%) were HIV-1-seropositive. Tubo-ovarian abscesses (TOA) were found in 33% of HIV-1-infected and 15% of HIV-1-uninfected women (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.5). Among seropositive women, TOA was found in 55% of those with CD4 cell percent <14% vs. 28% with CD4 cell percent>14% (OR 3.1, 95% CI 0.6-15.3). Neisseria gonorrhoeae was detected in 37 women (28%) and Chlamydia trachomatis in 12 (9%); neither was significantly related to HIV-1 seropositivity. Length of hospitalization was not affected by HIV-1 serostatus overall but was prolonged among HIV-1-infected women with CD4 cell percent <14%. Among patients with acute salpingitis, likelihood of TOA was related to HIV-1 infection and advanced immunosuppression. In general, HIV-1-seropositive women with acute salpingitis responded well to treatment.
JOAB PROFBWAYOJOB. "HLA-DR 52-and 51-associated DRB1 alleles in Kenya, East Africa. V. A. Dunand, C,-M.Ng2, J.A. Wade, Bwayo JJ, F. A. Plummer, and K. S. MacDonald. Tissue Antigen 1997 49:397-402.". In: Tissue Antigen 1997 49:397-402. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB, O. PROFANZALAAGGREY. "Long-term survivors in Nairobi: complete HIV-1 RNA sequences and immunogenetic associations. Fang G, Kuiken C, Weiser B, Rowland-Jones S, Plummer F, Chen CH, Kaul R, Anzala AO, Bwayo JJ, Kimani J, Philpott SM, Kitchen C, Sinsheimer JS, Gaschen B, Lang D, .". In: Burger HJ Infect Dis. 2004 Aug 15;190(4):697-701. John Benjamins Publishing Company; 2004. Abstract
OBJECTIVE: To determine the prevalence of HCV infection and HCV/HIV co-infection among voluntary blood donors at the National Blood Transfusion Centre and clients at the Kenyatta National Hospital HIV-Voluntary Counseling and Testing (VCT) Centre. DESIGN: A prospective cross-sectional descriptive study. SETTING: Kenyatta National Hospital, a tertiary referral and teaching hospital and the National Blood Transfusion Services Centre, Nairobi. SUBJECTS: Volunteer blood donors and VCT attendants. RESULTS: The prevalence of HCV/HIV co-infection among 6154 blood donors in the NBTSC was very low, at 0.02. The HIV prevalence among the 353 KNH HIV-VCT clients was 9.3%, none of the clients tested positive for HCV. The incidence of risk factors in the persons with HCV and/or HIV infection(s) was low. CONCLUSION: The prevalence of HCV infection among pre-screened volunteer blood donors was low. However the current practice of screening all donated blood for HCV remains indispensable to prevent its transmission to blood recipients.
JOAB PROFBWAYOJOB. "Female-to-male infectivity of HIV-1 among circumcised and uncircumcised Kenyan men. Baeten JM, Richardson BA, Lavreys L, Rakwar JP, Mandaliya K, Bwayo JJ, Kreiss JK.J Infect Dis. 2005 Feb 15;191(4):546-53.". In: J Infect Dis. 2005 Feb 15;191(4):546-53. Asian Economic and Social Society; 2005. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Maternal HIV?1 infection and pregnancy outcome.Termmerman M. Chomba E.N, Plummer FA, Bwayo JJ, Nyongo AA, Coppens M,Nagelkerke N, Piot P.Obstet Gynecol, 1993.( Am-J-Obstet-Gynecol. 1995 Feb; 172(2 Pt 1): 700-5).". In: Am-J-Obstet-Gynecol. 1995 Feb; 172(2 Pt 1): 700-5. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB, M. DROTIDOJULIUS. "Traditional healers and the management of sexually transmitted diseases in Nairobi, Kenya. Kusimba J, Voeten HA, O'hara HB, Otido JM, Habbema JD, Ndinya-Achola JO, Bwayo JJ. Int J STD AIDS. 2003 Mar;14(3):197-201.". In: Int J STD AIDS. 2003 Mar;14(3):197-201. Asian Economic and Social Society; 2003. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Disseminated Mycobacterium avium infection among HIV-infected patients in Kenya. Gilks CF; Brindle RJ; Mwachari C; Batchelor B; Bwayo JJ; Kimari J; Arbeit RD; von Reyn CF. J Acquir Immune Defic Syndr Hum Retrovirol. 1995 Feb 1;8(2):195-8.". In: J Acquir Immune Defic Syndr Hum Retrovirol. 1995 Feb 1;8(2):195-8. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Health-seeking and sexual behaviors among primary healthcare patients in Nairobi, Kenya. Fonck K, Mwai C, Ndinya-Achola J, Bwayo JJ, Temmerman M. Sex Transm Dis. 2002 Feb;29(2):106-11.". In: Sex Transm Dis. 2002 Feb;29(2):106-11. Asian Economic and Social Society; 2002. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Long distance truck-drivers: 1. Prevalence of sexually transmitted diseases (STDs). Bwayo JJ; Omari AM; Mutere AN; Jaoko W; Sekkade-Kigondu C; Kreiss J; Plummer FA. East Afr Med J. 1991 Jun;68(6):425-9.". In: East Afr Med J. 1991 Jun;68(6):425-9. Asian Economic and Social Society; 1991. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Risk factors for postnatal mother-child transmission of HIV-1. Embree JE, Njenga S, Datta P, Nagelkerke NJ, Ndinya-Achola JO, Mohammed Z, Ramdahin S, Bwayo JJ, Plummer FA. AIDS. 2000 Nov 10;14(16):2535-41.". In: AIDS. 2000 Nov 10;14(16):2535-41. Asian Economic and Social Society; 2000. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "Jackson DJ, Ngugi EN, Plummer FA, Kirui P, Kariuki C, Ndinya-Achola JO, Bwayo JJ, Moses S.Stable antenatal HIV-1 seroprevalence with high population mobility and marked seroprevalence variation among sentinel sites within Nairobi, Kenya. AIDS. 1999 Apr 1;.". In: AIDS. 1999 Apr 1;13(5):583-9. Asian Economic and Social Society; 1999. Abstract
OBJECTIVES: To monitor and analyse trends in HIV-1 seroprevalence among antenatal women in Nairobi, Kenya. DESIGN: Six sequential surveys were carried out among antenatal clinic attenders at four Nairobi City Council health centres between November 1991 and April 1997. METHODS: A total of 6828 women attending for first antenatal clinic visit were administered a standard questionnaire to obtain demographic information and were screened for HIV-1. RESULTS: HIV-1 seroprevalence rose from 12.1% in the first survey to 16.2% in the third, completed in October 1993. No rise was observed in subsequent surveys, and seroprevalence among women under the age of 20 declined after the third survey. Significant differences in seroprevalence (P < 0.001) were observed in all survey rounds between women who reported that their province of origin was Nyanza (22.4% overall), compared with those from other provinces in western Kenya (14.1%), and the eastern group of provinces (8.9%). The rise in HIV-1 seroprevalence observed between 1991 and 1993 was almost entirely attributable to the rising seroprevalence among women from Nyanza. There were considerable differences in HIV-1 seroprevalence among the four health centres, partly accounted for by differences in the proportion of clinic attenders from different provinces of origin, which also changed significantly over time. CONCLUSIONS: HIV-1 seroprevalence has stabilized in antenatal women attending these health centres in Nairobi, and may be declining among women in the youngest age group. This may reflect stabilization of HIV-1 incidence, but further observation is required. The levels of infection among Nairobi residents reflect the evolution of the HIV epidemic in their provinces of origin, and changing client composition influences HIV-1 seroprevalence at different clinics. HIV sentinel surveillance should be carried out at multiple sites in large urban centres to monitor accurately the evolution of the HIV epidemic and the impact of control efforts in reducing transmission.
JOAB PROFBWAYOJOB. "Genital shedding of human immunodeficiency virus type 1 DNA during pregnancy: association with immunosuppression, abnormal cervical or vaginal discharge, and severe vitamin A deficiency. John GC; Nduati RW; Mbori-Ngacha D; Overbaugh J; Welch M; Richardson.". In: J Infect Dis. 1997 Jan; 175(1):57-62. Asian Economic and Social Society; 1997. Abstract
{ OBJECTIVE: To establish a cohort of high-risk individuals suitable for HIV-prevention trials, and to measure changes in sexual behaviour and sexually transmitted disease (STD) incidence after a behavioural intervention. DESIGN: Prospective cohort study in trucking company depots in Mombasa, Kenya. PARTICIPANTS: A total of 556 male HIV-seronegative employees of trucking companies. INTERVENTIONS: HIV serological testing, individual counselling, condom promotion, STD diagnosis and management. MAIN OUTCOME MEASURES: Sexual risk behaviour and symptomatic STD incidence. RESULTS: Using time-trend modelling, significant declines in self-reported high-risk sexual behaviour were demonstrated during a 1-year follow-up. The percentage of men reporting any extramarital sex during the 3-month period prior to a follow-up visit decreased from 49% durig the first quarter of follow-up to 36% during the last quarter (P < 0.001). The decline in reported female sex worker contact was from 12% to 6% (P = 0.001). Approximately 30% of men reported consistent condom use during extramarital sex and this percentage remained unchanged during the study period. The incidence of STD declined from 34 per 100 person years (PY) during the first quarter to 10 per 100 PY during the last quarter (P = 0.001). Significant reductions in gonorrhoea (15 to five cases per 100 PY
JOAB PROFBWAYOJOB. "Risk factors for Chlamydia trachomatis pelvic inflammatory disease among sex workers in Nairobi, Kenya. Kimani J; Maclean IW; Bwayo JJ; MacDonald K; Oyugi J; Maitha GM; Peeling RW; Cheang M; Nagelkerke NJ; Plummer FA Brunham RC. J Infect Dis. 1996 Jun;173.". In: J Infect Dis. 1996 Jun;173(6):1437-44. Asian Economic and Social Society; 1996. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
JOAB PROFBWAYOJOB. "Knowledge and practice about cervical cancer and Pap smear testing among patients at Kenyatta National Hospital, Nairobi, Kenya. Gichangi P, Estambale B, Bwayo JJ, Rogo K, Ojwang S, Opiyo A, Temmerman M. Int J Gynecol Cancer. 2003 Nov-Dec;13(6):827-33.". In: Int J Gynecol Cancer. 2003 Nov-Dec;13(6):827-33. Asian Economic and Social Society; 2003. Abstract
Background. The host immune response against mucosally-acquired pathogens may be influenced by the mucosal immune milieu during acquisition. Since Neisseria gonorrhoeae can impair dendritic cell and T cell immune function, we hypothesized that co-infection during HIV acquisition would impair subsequent systemic T-cell responses.   Methods. Monthly screening for sexually transmitted infections (STIs) was performed in high risk, HIV seronegative Kenyan female sex workers as part of an HIV prevention trial. Early HIV-specific CD8+ T cell responses and subsequent HIV viral load set point were assayed in participants acquiring HIV, and were correlated with the presence of prior genital infections during HIV acquisition.   Results. Thirty-five participants acquired HIV during follow up, and 16/35 (46%) had a classical STI at the time of acquisition. N. gonorrhoeae co-infection was present during HIV acquisition in 6/35 (17%), and was associated with an increased breadth and magnitude of systemic HIV-specific CD8+ T-cell responses, using both interferon- (IFNg) and MIP-1 beta (MIP1b) as an output. No other genital infections were associated with differences in HIV-specific CD8+ T cell response, and neither N. gonorrhoeae nor other genital infections were associated with differences in HIV plasma viral load at set point.   Conclusion. Unexpectedly, genital N. gonorrhoeae infection during heterosexual HIV acquisition was associated with substantially enhanced HIV-specific CD8+ T-cell responses, although not with differences in HIV viral load set point. This may have implications for the development of mucosal HIV vaccines and adjuvants.
JOAB PROFBWAYOJOB. "In vitro stimulation of peripheral blood mononuclear cells (PBMC) from HIV- and HIV+ chancroid patients by Haemophilus ducreyi antigens. Van Laer L; Vingerhoets J; Vanham G; Kestens L; Bwayo JJ; Otido J; Piot P; Roggen E. Clin Exp Immunol. 1995 Nov;102(2).". In: Clin Exp Immunol. 1995 Nov;102(2):243-50. Asian Economic and Social Society; 1995. Abstract
The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.
Joab O Odhiambo, Ngare P, Weke P, Otieno RO. "Modelling of covid-19 transmission in kenya using compound poisson regression model." Journal of Advances in Mathematics and Computer Science. 2020; 35(2):101-111. AbstractWebsite

Since the inception of the novel Corona Virus Disease-19 in December in China, the spread has been massive leading World Health Organization to declare it a world pandemic. While epicenter of COVID-19 was Wuhan city in China mainland, Italy has been affected most due to the high number of recorded deaths as at 21st April, 2020 at the same time USA recording the highest number of virus reported cases. In addition, the spread has been experienced in many developing African countries including Kenya. The Kenyan government need to make necessary plans for those who have tested positive through self-quarantine beds at Mbagathi Hospital as a way of containing the spread of the virus. In addition, lack of a proper mathematical model that can be used to model and predict the spread of COVID-19 for adequate response security has been one of the main concerns for the government. Many mathematical models have been proposed for proper modeling and forecasting, but this paper will focus on using a generalized linear regression that can detect linear relationship between the risk factors. The paper intents to model and forecast the confirmed COVID-19 cases in Kenya as a Compound Poisson regression process where the parameter follows a generalized linear regression that is influenced by the number of daily contact persons and daily flights with the already confirmed cases of the virus. Ultimately, this paper would assist the government in proper resource allocation to deal with pandemic in terms of available of bed capacities, public awareness campaigns and virus testing kits not only in the virus hotbed within Nairobi capital city but also in the other 47 Kenyan counties.

Joab Odhiambo, Weke P, Wendo J. "Modeling of Returns of Nairobi Securities Exchange 20 Share Index Using Log-Normal Distribution ." Research Journal of Finance and Accounting. 2020;11(8). AbstractWebsite

Nairobi Securities Exchange 20 Index Share (NSE-20 Share Index/ An Exchange Traded Fund) has been one of
the investment avenues for both Kenyans and foreign investors look whenever they want to make sound
investments decisions in the market. However, the assumption that the daily securities index prices follows a
normal distribution has been disputed by data in several cases. This means new statistical distributions must be
used to discern the distribution of NSE-20 Share Index thus enabling investors make prudent financial decisions
to avoid financial loses. In this research paper, we will model the prices of daily securities index using a log-normal
distribution. This is because the distribution follows a positive trend before we can ascertain on how well it fits
the already available data at the NSE market. This research paper recommends that a log-normal distribution best
fits data of the daily prices of NSE-20 Share Index for those investors who would like to model the future of the
market before making financial decisions.

Joab Odhiambo, Weke P, Ngare P. "Modeling Kenyan economic impact of corona virus in Kenya using discrete-time Markov chains." Journal of Finance and Economics. 2020;8(2):, 80-85. AbstractWebsite

Since the outbreak of pandemic COVID-19 (Corona virus), many countries have continued to suffer
economically leading to massive losses in terms of trillions of dollars globally in terms of trade loses. In reaction to
this effect, many countries in the world have taken emergency measures to ensure that the impact does not lead to
huge economic and financial implications in terms of rapid recession. In Africa, where many countries have taken
measures to deal with global recession to the citizens especially through fiscal and monetary policies, which includes
Kenya. In addition, the social economic statues have continued to change instantaneously and stochastically
more so after huge number of populations losing their daily informal jobs with new measures to stop the spread of
COVID-19 virus. This paper seeks to model the effect of COVID-19 pandemic on Kenyan Gross Domestic Product
(GDP) contributors using a Discrete-time Markov Chain Analysis. In addition, the paper seeks to find the ultimate
effect of the Covid-19 to the top five key sectors of the Kenyan economy that contributes massively to GDP growth
by looking at the proportion of the contributors at steady state. Moreover, the results from this paper should help the
government of Kenya as well as global investors to understand different economic stimulus planning packages to
launch in the “hard-hit” sectors of the economy to reduce the impact of the potential economic recession. Ultimately,
the information should be help in formulating a post COVID-19 economic recovery plan for the Kenyan economy
but also act as a benchmark strategy for many other countries in Africa that has economic and financial dynamics
similar to that of Kenya

Joag V, Obila O, Gajer P, Scott M, Dizzell S, Humphrys M, Shahabi K, Huibner S, Shannon B, Tharao W, MW MUREITHI, Julius Oyugi,, J.N Kiiru, et al. Impact of bacterial vaginosis treatment on ex vivo HIV susceptibility in the female genital tract.Journal of Allergy and Clinical Immunology.; 2018.
and Joan M.Tenge, Isaac O.Jumba DKKDRO. "An Investigation to Establish the Presence, Quality and Rank of Coal from Parts of Mui Basin in Kenya." International Journal of Science and Research. 2013;2(8):329-334.
Joel O. Dissemination of Agricultural Information : a case study of KADOC. Nairobi: Technical University ; 1993.
Joelle Chateauneuf, Samuel Kimani AKJKES-SKM. "Kenya Heart and Sole Quick Look Guide for Cardiovascular Disease Patient Evaluation." Journal of Cardiovascular Nursing. 2011;26(4):278-279.
Johannessen AC, Vintermyr OK, Gjertsen BT, Bredholt T, Neppelberg E, Dimba EA, Costea D. "Khat induces G1-phase arrest and increased expression of stress-sensitive p53 and p16 proteins in normal human oral keratinocytes and fibroblasts.". 2008. Abstract
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Johannsson, et al. "Air breathing in Magadi tilapia Alcolapia grahami, under normoxic and hyperoxic conditions, and the association with sunlight and reactive oxygen species." Journal Fish Biology. 2014;84(3):844-863. Abstractwileyonlinelibrary.com

Observations of the Magadi tilapia Alcolapia grahami in hot, highly alkaline Lake Magadi revealed that they air breathe not only during hypoxia, as described previously, but also during normoxia and hyperoxia. Air breathing under these latter conditions occurred within distinct groupings of fish (pods) and involved only a small proportion of the population. Air breathing properties (duration and frequency) were quantified from video footage. Air breathing within the population followed a diel pattern with the maximum extent of pod formation occurring in early afternoon. High levels of reactive oxygen species (ROS) in the water may be an irritant that encourages the air-breathing behaviour. The diel pattern of air breathing in the field and in experiments followed the diel pattern of ROS concentrations in the water which are amongst the highest reported in the literature (maximum daytime values of 2·53–8·10 μM H2O2). Interlamellar cell masses (ILCM) occurred between the gill lamellae of fish from the lagoon with highest ROS and highest oxygen levels, while fish from a normoxic lagoon with one third the ROS had little or no ILCM. This is the first record of air breathing in a facultative air-breathing fish in hyperoxic conditions and the first record of an ILCM in a cichlid species.
Key words: diel patterns; gill remodelling; interlamellar cell mass.
© 2014 The Fisheries Society of the British Isles

Johannsson, et al. "Characteristics of Air Breathing in Lake Magadi Tilapia: is there a relationship with Diel Patterns in Reactive Oxygen Species (ROS) in the Lake?". In: The Canadian Society of Zoologists meeting. Mount Allison University, Sackville, NB Canada.; 2012.
Johansen, K; Maloiy GGMO; H. Temperature regulation in the naked mole rat.; 1976.
Johari Mfalamagoha, Oyieke J, Blasio Omuga, Omoni G. "Knowledge, attitude and practices of midwives toward HIV/AIDS positive mothers." Women and Birth. 2015:S49-S50.
JOHN PROFNJENGAMUNENE. "M.J Njenga, E K Kangethe, O Bwangamoi, S J M Munyua, G. M Mugera and E R Mutiga(1999). Experimental transmission of Besnoitia caprae in goats. Journal of South African Veterinary Association 70(4) 161-163.". In: Journal of South African Veterinary Association 71 (1): 47-52. ELOQUENT BOOKS NY, Strategic Book Group, Connecticut, USA. ISBN-978-1-60911-081-9.Pages1; 1999. Abstract
A case of dystocia resulting in rupture of he middle uterine artery and subsequent death in a cow is reported
JOHN MRNDOLOISAAC. "Ndolo, I.J. (1998): Some Aspects of the Urban Microclimate of Nairobi City.". In: African Urban Quarterly Journal. Association of Africa Universities; 1998. Abstract
Vertex epidural haematomas (VEDH) are rare and difficulties are encountered in diagnosis and management. This is a case report of a patient with a vertex epidural haematoma who presented with signs of severe head injury with upper limb decerebrate posture. We discuss the challenges of radiological investigation and neurosurgical management of VEDH.
JOHN PROFADWOK. "Githaiga JW, JA Adwok. .". In: East Afr. Med. J. 2002; 79:450-452. AIBUMA Publishing; 2002. Abstract
The decision to pay out earnings or retain dividends has been a subject of debate for many scholars. The effect of dividend on the firm value and cost of capital have been covered in attempt to resolve the dividend puzzle. This research paper tests the applicability of constant dividend model by companies listed at the Nairobi stock exchange. Data was collected from annual reports and share price schedules obtained from Nairobi stock exchange and Capital market Authority for a population of 20 companies that paid dividends consistently from 2002 to 2008. The data was then analyzed by re-computing the dividends that should have been paid if the dividend constant model was applied. This recomputed figure was later compared to the dividend as paid out by the companies thought the years of study. Paired sample t-test statistic was also performed to determine whether there is a significant difference between the two dividend figures. The findings of the research established that the dividend model was not employed by the companies listed at the Nairobi stock exchange. Most firms instead adopted stable and predictable policy where a specific amount of dividend per share each year was paid periodically. In some years there was a slight adjustment of the dividend paid after an increase in earnings, but only by a sustainable amount. The study shows that the relationship between the stock market prices and the dividend paid from the constant dividend model is uneven from one year to another and where there was a relationship it was insignificant. Though a share would be highly priced, a high dividend per share was not always declared.
John GC, Bird T, Overbaugh J, R W Nduati, Mbori-Ngacha DA, Rostron T, Dong T, Kostrikis L, Richardson B, Rowland-Jones SL. "CCR5 Promoter Polymorphisms in a Kenyan Perinatal Human Immunodeficiency Virus Type 1 Cohort: Association with Increased 2-Year Maternal Mortality.". 2001. AbstractWebsite

The CCR5 chemokine receptor acts as a coreceptor with CD4 to permit infection by primary macrophage-tropic human immunodeficiency virus type 1 (HIV-1) strains. The CCR5Δ32 mutation, which is associated with resistance to infection in homozygous individuals and delayed disease progression in heterozygous individuals, is rare in Africa, where the HIV-1 epidemic is growing rapidly. Several polymorphisms in the promoter region of CCR5 have been identified, the clinical and functional relevance of which remain poorly defined. We evaluated the effect of 4 CCR5 promoter mutations on systemic and mucosal HIV-1 replication, disease progression, and perinatal transmission in a cohort of 276 HIV-1–seropositive women in Nairobi, Kenya. Mutations at positions 59353, 59402, and 59029 were not associated with effects on mortality, virus load, genital shedding, or transmission in this cohort. However, women with the 59356 C/T genotype had a 3.1-fold increased risk of death during the 2-year follow-up period (95% confidence interval [CI], 1.0–9.5) and a significant increase in vaginal shedding of HIV-1–infected cells (odds ratio, 2.1; 95% CI, 1.0–4.3), compared with women with the 59356 C/C genotype.

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