Gastroenteritis is a catchall term for infection or irritation of the digestive tract, particularly the stomach and intestine. It is frequently called stomach or intestinal flu, although the influenza virus is not associated with this illness. Major symptoms include nausea and vomiting, diarrhea, and abdominal cramps. These symptoms are sometimes also accompanied by fever and overall weakness. Gastroenteritis typically lasts about three days. Adults usually recover without problems, but children, the elderly, and people with underlying disease are more vulnerable to complications such as dehydration.

Gastroenteritis is rarely life-threatening in the United States and other developed nations. However, an estimated 220,000 children younger than age five are hospitalized with gastroenteritis symptoms in the United States annually. Of these, 300 die as a result of severe diarrhea and dehydration. In developing nations, diarrheal illnesses are a major cause of death. In 1990, approximately three million deaths occurred worldwide as a result of...