Viral gastroenteritis is an infection caused by a variety of viruses that results in vomiting or diarrhea. It is often called the "stomach flu," although it is not caused by the influenza viruses.
The main symptoms of viral gastroenteritis are watery diarrhea and vomiting. The person may also have headache, fever, and abdominal cramps ("stomach ache"). In general, the symptoms begin 1 to 2 days following infection with the virus and may last for 1 to 10 days, depending on which virus causes the illness. Dehydration is the most common complication, especially among the young and elderly, and may require medical attention. The viruses that cause gastroenteritis are spread through close contact with infected persons. Individuals may also become infected by eating or drinking contaminated foods or beverages.