Gastrenteritis is an intestinal infection marked by watery diarrhea, abdominal cramps, nausea or vomiting, and sometimes fever.
The most common way to develop viral gastroenteritis — often called stomach flu —is through contact with an infected person or by ingesting contaminated food or water. If you're otherwise healthy, you'll likely recover without complications. But for infants, older adults and people with compromised immune systems, viral gastroenteritis can be deadly.
There's no effective treatment for viral gastroenteritis, so prevention is key. In addition to avoiding food and water that may be contaminated, thorough and frequent hand-washings are your best defense.
Although it's commonly called stomach flu, gastroenteritis isn't the same as influenza. Real flu (influenza) affects only your respiratory system — your nose, throat and lungs. Gastroenteritis, on the other hand, attacks your intestines, causing signs and symptoms, such as:
- Watery, usually nonbloody diarrhea — bloody diarrhea usually means you have a different, more severe infection
- Abdominal cramps and pain
- Nausea, vomiting or both
- Occasional muscle aches or headache
- Low-grade fever
Depending on the cause, viral gastroenteritis symptoms may appear within one to three days after you're infected and can range from mild to severe. Symptoms usually last just a day or two, but occasionally they may persist as long as 10 days.
Because the symptoms are similar, it's easy to confuse viral diarrhea with diarrhea caused by bacteria, such as Clostridium difficile, salmonella and E. coli, or parasites, such as giardia.