Norovirus, sometimes also called the Norwalk virus, causes the intestinal flu. People infected with a norovirus, generally experience stomach cramps, diarrhea, vomiting, and slight fever. Norovirus often occurs in outbreaks. It is a common cause of high numbers of people being ill on cruise ships. It can also sweep through a convalescent home or school with ease.

Failure to properly wash the hands after using the bathroom usually transmits norovirus to others. Coming into contact with hands or food that is prepared by hands that are contaminated with molecules of infected stool can cause outbreaks. Sometimes exposure to raw sewage may also cause outbreaks of norovirus. Most commonly however, an outbreak begins with a person who is infected preparing food for others without thoroughly washing the hands.

For example, on a cruise ship, a person who has not washed his hands and then cut fruit for a large fruit salad could infect high numbers of people. Incubation for the illness is usually about one to two days. This means people exposed to norovirus get sick quite rapidly after exposure.

In healthy populations, norovirus is uncomfortable, inconvenient, and miserable. However, usually no interventions are needed as healthy people normally recover in about 24-48 hours. The course of norovirus in the elderly, the very young, or in those with serious illnesses may be more complicated.

In young children, constant vomiting and diarrhea can quite easily lead to dehydration. If you believe a child has been exposed to norovirus, it may be best to visit a doctor, particularly if symptoms do not resolve within the first 24 hours. With the elderly and medically fragile, dehydration may also be a factor. Norovirus can also complicate other illnesses.

Some people may require hospitalization and intravenous fluids in order to recover from norovirus without risking serious dehydration. Dehydration can also prolong symptoms of vomiting, and severe dehydration can lead to organ shut down. If one’s symptoms fail to resolve in a day or so, one should see a physician.

In order to prevent transmission, people should always thoroughly wash the hands with warm, soapy water after using the bathroom, and before eating. If one is ill with the stomach flu, he or she should try to stay away from others. Children should be kept home from school until symptoms have resolved. Workers in the food industry especially should not attend work when they have the stomach flu.