Bacillus cereus food intoxication
Bacillus cereus food intoxication is a common foodborne intoxication causing vomiting or diarrhea in people who eat improperly refrigerated cooked rice or meat.
CASES/YEAR
27,360 (US); 547,200 (Global)
OTHER NAMES
B. cereus preformed toxin or diarrheal toxin;
INCUBATION
Preformed toxin: 1-6 hours; Diarrheal toxin: 8-16 hours; [Harrisons, p. 404]
INITIAL SYMPTOMS
Preformed toxin in contaminated fried rice: sudden onset of severe vomiting; Diarrheal toxin: abdominal cramping and diarrhea; [Harrisons, p. 404]
COMMENTS
The preformed toxin is the result of improperly refrigerated cooked rice and meats. The diarrheal toxin is associated with meats, stews, and gravies. The illnesses are self-limited within 24-48 hours and require supportive care only. [Foodborne Illnesses. MMWR. 4/16/04] The emetic toxin that causes vomiting is heat stable. It is formed when the level of B. cereus in food reaches 100,000 colony-forming units per gram. The diarrheal toxin is heat labile, and it is formed by the bacteria growing in the intestine of the host. B. cereus bacteria are spore-forming, and the spores are resistant to boiling. The bacteria are common in the soil and also in raw and processed food. The emetic toxin is associated with contaminated fried rice. Outbreaks of vomiting occur after cooked rice is held at room temperature before reheating. [CCDM, p. 222] After boiling or frying rice, it should be kept at >60 deg C or rapidly cooled <8 deg C to prevent the germination of spores at room temperature. [ABX Guide: Bacillus species]
DIAGNOSTIC
Clinical; Send samples to reference lab for culture and toxin identification if necessary.
SIGNS & SYMPTOMS
-
G abdominal pain
-
G diarrhea
-
G nausea, vomiting
SOURCE
Soil or Dust (Ingesting or Inhaling), Eating Contaminated Food, Eating Contaminated or Infected Meat, Eating Contaminated Produce
RISK FACTORS
- Ingest toxins in food or water
TREATMENT
No antimicrobial therapy;
REFERENCES FOR CASES/YEAR
1. (US) Estimated 27,360 cases in 1997; [Mead1999: PMID 10511517]
2. (Global) Use US cases/yr X 20 = 547,200;