(Viral Gastroenteritis, "Stomach Flu")
What is viral gastroenteritis?
Gastroenteritis means inflammation of the stomach and small and large intestines. 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.
What causes viral gastroenteritis?
Many different viruses can cause gastroenteritis, including
noroviruses; adenoviruses, types 40 and 41; sapoviruses; and astroviruses. Viral gastroenteritis is not caused by bacteria (such as
Salmonella species or
Escherichia coli), or parasites (such as
Giardia lamblia), or by medications, or other medical conditions, although the symptoms may be similar. Your doctor can determine if the diarrhea is caused by a virus or by something else.
What are the symptoms of viral gastroenteritis?
The main symptoms of viral gastroenteritis are watery diarrhea and vomiting. The affected person may also have headache,
fever, and abdominal cramps ("stomach ache"). In general, the symptoms begin 1 to 2 days following infection with a virus that causes gastroenteritis and may last for 1 to 10 days, depending on which virus causes the illness.
Is viral gastroenteritis a serious illness?
For most people, it is not. People who get viral gastroenteritis almost always recover completely without any long-term problems. Gastroenteritis is a serious illness, however, for persons who are unable to drink enough fluids to replace what they lose through vomiting or diarrhea. Infants, young children, and persons who are unable to care for themselves, such as the disabled or elderly, are at risk for dehydration from loss of fluids. Immune compromised persons are at risk for dehydration because they may get a more serious illness, with greater vomiting or diarrhea. They may need to be hospitalized for treatment to correct or prevent dehydration.