Prevalence of enterotoxigenic Bacillus cereus and its enterotoxins in milk and products in and around Nairobi

NYARONGI PROFOMBUIJ. "Prevalence of enterotoxigenic Bacillus cereus and its enterotoxins in milk and products in and around Nairobi.". In: journal. University of Nairobi Press; 2005.


Objectives: To determine the prevalence of enterotoxigenic Bacillus cereus (B. cereus) and enterotoxingens in milk and milk products.
Design: A random sampling of milk products was carried out.
Setting: Market milk and milk products were collected from retail shops in Nairobi and analysed for contamination with enterotoxigenic B. cereus and its enterotoxins using reverse passive latex agglutination and TECRA ELISA immunoassay test.
Subjects: Ninety six milk samples including 36 raw milk, 42 pasteurized milk, 10 yoghurt and eight fermented milk samples. Forty seven B. cereus isolated from milk and milk products.
Main outcome measures: Isolation of enterotoxigenic B. cereus from milk and milk products and detection of B. cereus hemolytic (hemolysin BL) and non-hemolytic enterotoxins in milk.
Results: Fifty seven percent of the samples were contaminated with B. cereus. Eighty one percent (38 out of 47) of the isolates produced non-hemolytic enterotoxins, while 25(53.2%) of the isolates produced hemolysin BL. Eigtheen (38.3%) of the isolates produced both hemolysin BL and non-henolytic enterotoxins. About 14.3% of the pasteurized milk samples tested positive for non-hemolytic enterotoxin.
Conclusions: Enterotoxigenic B. cereus and enterotoxins occur in market milk and their presence poses a potential risk of causing food poisoning. The risk can be reduced if milk products undergoes thorough quality control checks and be kept always at below 4oC till consumption. Post pasteurization contamination which is commonly blamed for spoilage of milk products by B. cereus is not necessarily the most important source of the organism.




UoN Websites Search