Staphylococcal foodborne illness is characterized by the abrupt and sometimes violent onset of severe nausea, abdominal cramps, vomiting, and prostration, often accompanied by diarrhea. Low-grade fever or mild hypothermia can occur. The duration of illness typically is 1 to 2 days, but the intensity of symptoms may require hospitalization. The short incubation period, brevity of illness, and usual lack of fever help distinguish staphylococcal from other types of food poisoning except that caused by Bacillus cereus . Chemical food poisoning usually has an even shorter incubation period. Clostridium perfringens food poisoning usually has a longer incubation period and commonly is not accompanied by vomiting. Patients with foodborne Salmonella or Shigella infection usually have fever and a longer incubation period (see Appendix IX, Clinical Syndromes Associated With Foodborne Diseases).