title: Prevalence of Bacillus cereus and associated risk factors in Chinese-style fried rice available in the city of Colombo, Sri Lanka.
abstract: The present study aimed to assess the prevalence of Bacillus cereus and its associated risk factors in Chinese-style fried rice available in Colombo city. In 200 samples of fried rice the prevalence of B. cereus was 56%. The prevalence by variety of fried rice was chicken (20.0%), vegetable (18.0%), seafood (10.0%), egg (5.0%), mixed (2.0%), and beef (1.0%). Of analyzed samples, 28 (14%) had colony counts >10(6) colony forming units per gram (cfu/g), the infectious dose for B. cereus food borne outbreaks. Occurrence of >10(6) cfu/g of B. cereus were associated with storage of boiled rice at room temperature (p=0.030), >4 hours of storage at room temperature (p=0.042) and cooking frequency of more than once per dining session (p=0.017). The type of rice and the quantity boiled per day were not independent risk factors for high B. cereus counts. Majority of B. cereus isolates (53.7%) in this study were not typable. The serotypes observed included H15 (14.3%), H19 (14.3%), and H20 (10.7%). These serotypes are known to be associated with both emetic and diarrheal syndromes. All isolates were sensitive to ciprofloxacin (100%), erythromycin (100%), gentamicin (100%), chloramphenicol (100%), and amikacin (100%) whereas 100% resistance was observed for penicillin with minimal inhibitory concentration range of 32-256 μg/mL.
authors.affiliation: Molecular Biology Section, Medical Research Institute, Colombo, Sri Lanka. manosha_lakmali@yahoo.com
authors.forename: Manosha Lakmali
authors.initials: ML
authors.lastname: Perera
authors.forename: Gerard Ranjan
authors.initials: GR
authors.lastname: Ranasinghe
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D044466:Asian People; D001409:Bacillus cereus / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*; D002417:Cattle; D002645:Chickens / Q000382:microbiology; D015169:Colony Count, Microbial; D005506:Food Contamination / Q000032:analysis*; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D006801:Humans; D008460:Meat / Q000382:microbiology*; D012275:Oryza / Q000382:microbiology*; D010063:Ovum / Q000382:microbiology; D015995:Prevalence; D012307:Risk Factors; D017747:Seafood / Q000382:microbiology*; D013171:Spores, Bacterial; D013188:Sri Lanka / Q000453:epidemiology; D013696:Temperature; D013997:Time Factors; D014675:Vegetables / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents