There are two types of illnesses associated with Bacillus cereus. The most common is a diarrheal illness accompanied with abdominal pain. An incubation period of 4 to 16 hours is followed by symptoms lasting 12 to 24 hours.
The second type of illness is an emetic illness often associated with ingestion of rice not properly refrigerated after cooking. This illness is characterized by vomiting and nausea that usually occur within 1 to 5 hours upon ingestion of the contaminated food.
