Bacillus cereus is an impoant cause of food poisoning. Two patterns: diarrheal and emetic. Diarrheal: associated with cooked meat and vegetables. Diarrhea and abdominal pain 8-16 hours after the ingestion of contaminated food. Vomiting rarely. Bacilli are not found in the fecal specimen of these patients. Emetic: associated with consumption of cooked rice, usually fried rice from restaurants. Nausea and vomiting 1-5 hours after the meal. Bacilli are present in large numbers in cooked rice and fecal samples from these patients. such strains produce a toxin resembling staphylococcal enterotoxin, which is a preformed toxin. The emetic toxin was produced only when the Bacillus cereus is grown in rice, not in other media. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 254