Stomach flu is an infection that is caused by a virus. Medically referred to as viral gastroenteritis, it afflicts both the stomach and the small intestine. This disease is not at all related to influenza, despite the similar common name, and it is not caused by one particular virus. The name is simply used as a catchall phrase to describe almost any viral illness that affects the digestive system.
The most common symptoms of the stomach flu are nausea, vomiting, and diarrhea. Often, a person with this condition will also have stomach cramps and chills, and a mild fever, fatigue, appetite loss, and muscle aches are also common symptoms of stomach viruses. The symptoms may develop gradually over many hours or the onset may be quite sudden; generally, symptoms last from one to three days. The stomach flu is diagnosed based on a healthcare provider's review of a patient's symptoms; lab tests also may be given to make certain a more serious illness is not responsible, as well as to look for more serious complications.
Among the causes of stomach flu are rotaviruses, adenoviruses, and the Norwalk virus. The viruses are contained in the bodily fluids of infected individuals, and can be spread whenever these fluids are swallowed by someone else. For example, an individual may get it from kissing or sharing food or eating utensils with an infected person. People can even contract it by shaking hands with an infected individual or touching a surface that person has also touched, and then eating without washing the hands properly.
The virus may be present in the body even before symptoms appear, and may be spread without the carrier knowing. Once an uninfected person encounters the bodily fluids of an infected individual and swallows the virus, trouble begins. The virus travels down to the stomach and on to the intestines, causing inflammation in both places. This temporarily impairs the function of these organs and symptoms become obvious and unpleasant.
Treatment for the stomach flu mostly involves resting the digestive system. This means avoiding solid foods for a period of time and staying hydrated with clear liquids. Once vomiting is under control, soft, bland foods may be consumed. If vomiting is frequent, patients should only drink small sips of water. Though it is important to stay hydrated while dealing with the stomach flu, too much liquid at once can cause vomiting to increase.
Water is generally a good choice for staying hydrated during the stomach flu, although an electrolyte-replacement drink may be a better idea if vomiting has continued for a long period of time. Weak tea may also be consumed, and some people find that drinking flat, decaffeinated soda can help relieve nausea. Patients should usually avoid milk, citrus juice, caffeine, and carbonated beverages while they are sick, or they risk making their digestive problems worse.