• Staphylococcus aureus and Bacillus cereus can cause acute food poisoning within 6 hours of ingestion of food. B. cereus is the likely cause when rice is the reason behind it.
  • B. cereus is able to persist in food processing environments on account of its ability to survive at extreme temperatures as well as its ability to form biofilms and spores.
  • B. cereus has been recovered from a wide range of foods, including rice, dairy products, spices, bean sprouts and other vegetables.
  • Fried rice is an important cause of emetic-type food poisoning linked with B. cereus.
  • The pathogen is found in uncooked rice, and heat-resistant spores have the potential to survive cooking.
  • Cooked rice subsequently at room temperature can allow vegetative forms to multiply, and the heat-stable toxin that is produced can survive brief heating.
  • B. cereus causes two types of toxin-mediated food poisoning -marked by either diarrhea or vomiting, based on the toxin involved. Vegetative cells produce the diarrheal toxin in the small intestine following the ingestion of either bacilli or spores. The emetic toxin is ingested directly from contaminated food. Both toxins can lead to disease within 24 hours of ingestion.
  • Heating can reduce the number of viable spores and vegetative bacteria that produce diarrheal toxin; however, spores associated with emetic toxin can survive heat.
  • The toxin cereulide has thermal stability and resists gastric conditions.
  • The ingested toxin can cause disease despite heating.
  • The emetic syndrome manifests as abdominal cramps, nausea, and vomiting. Diarrhea may also occur in about one-third of patients. Symptomsdevelop within 1 to 5 hours of ingestion, but can also develop within half an hour and up to six hours after ingestion of contaminated food.
  • Symptoms usually resolve in 6 to 24 hours.
  • Rice-based dishes are associated with emetic toxin-mediated disease. This could be attributed to cooling fried rice dishes overnight at room temperature and reheating them the next day.
  • Cereulide can cause symptoms at a dose of 8 to 10 micrograms per kilogram of body weight.