Robert Burakoff, MD, MPH, is board-certified in gastroentrology. He is the vice chair for ambulatory services for the department of medicine at Weill Cornell Medical College in New York.
Viral gastroenteritis—dubbed the "stomach flu"—is the second most common illness in the United States. It is not caused by the influenza virus, and it is not a respiratory illness. Instead, the stomach flu is caused by a contagious virus (frequently norovirus or rotavirus) that attacks the intestinal tract and causes inflammation, vomiting, and diarrhea.
Many people don’t wind up seeing a doctor for the stomach flu since symptoms usually pass on their own. However, if your symptoms are severe or last longer than a few days, make an appointment to see your health care provider. In addition, infants, children, and people with compromised immune systems, who are most at risk for dehydration, may require immediate medical treatment.
Symptom onset and duration depend on the virus causing your infection. For example, with norovirus—one of the most common causes of stomach flu—the typical time between exposure and the start of symptoms is about 12 to 48 hours. Symptoms of norovirus typically last one to three days, but diarrhea and intestinal discomfort can linger for up to 10 days.
In most cases, stomach flu doesn’t need to be treated by a physician. Home remedies, like getting plenty of fluids and eating a bland diet, can usually treat symptoms until the illness passes in otherwise healthy adults. Infants, children, and people who have a digestive disease or another serious illness should seek medical treatment to avoid complications.
You may not be able to eat when you’re in the initial stages of stomach flu since nausea and vomiting are common symptoms. When you’re able to keep fluids down, try ingesting clear liquids like water and chicken or vegetable broth. When you’re ready to try solid foods, start with small portions of bland, easily digestible, yet appealing food until your digestive system returns to normal.
Viral gastroenteritis can be caused by several different viruses. The two most common are norovirus and rotavirus. With norovirus, you are contagious as soon as your symptoms start. You are still contagious for three days after you recover and could spread the virus for up to two weeks. With rotavirus, you are contagious before symptoms appear and for two weeks after you recover.
This very rare disease of the intestinal tract has symptoms similar to other forms of gastroenteritis, such as nausea, vomiting, and diarrhea. Gastrointestinal bleeding and the intrusion of white blood cells, or eosinophils, into the gastrointestinal tract are additional features of this disease, which generally resolves quickly with corticosteroid treatment.
There are many viruses, bacteria, and parasites that can cause foodborne illness, which is also known as the stomach flu or food poisoning. Transmission can occur via food that is undercooked, improperly processed or canned, or prepared by someone who is sick. Contaminated water is another potential source, as is cross-contamination that occurs during food preparation.
Gastroenteritis is the medical term for the stomach flu. Symptoms, which include diarrhea and vomiting, occur as a result of inflammation of the stomach and intestines. Viruses, bacteria, and parasites may all cause gastroenteritis.
The influenza virus causes what’s known as the flu. Unlike the stomach flu, which attacks the digestive system, influenza affects the respiratory system. The influenza virus is spread through airborne droplets or contact with surfaces contaminated by these droplets. It is possible to get the flu if you've had it before, since there are many flu strains that are constantly mutating.
When gastroenteritis is caused by a virus, it is called viral gastroenteritis. The most common viruses that cause viral gastroenteritis include norovirus and rotavirus. Such viruses spread quickly via close contact with infected people, touching contaminated surfaces, or eating contaminated food.
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention. Updated norovirus outbreak management and disease prevention guidelines. MMWR Recomm Rep. 2011 Mar 4;60(RR-3):1-18.
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