Bacillus cereus subsp. mycoides (gram staining)
Bacillus cereus is a gram positive, spore forming, optionally anaerobic rod that belongs to the bacillus group and can cause diarrhea and vomiting.
Epidemiology
As the bacterium Bacillus cereus is ubiquitusly present in nature it can be found in the raw ingredients of many foods. The spores are vera resistant - they are killed neither by processing nor boiling.
A germ count of more than 1000 per gram food can lead to symptoms, as in such cases there is a presence of high levels of the toxin that is produced by the bacteria. At the same time there are hightened levels of proteases, which cause the unpleasant taste of the affected food.
Clinically
After the ingestion of food that contains hightened toxin levels the first symptom is vomiting. After many spores have reached the small intestine and germinated there, and enterotoxin produced by the bacteria can lead to diarrhea.
Diagnostics
The presence of the enterotoxin can be proven by immunological tests like for example the EIA. Since the illness is often very harmless, it often remains undiagnosed.
Source: CDC/ Dr. William A. Clark
