Norovirus is a microscopic organism that causes a common illness affecting the stomach and intestines in human beings. The illness is often described as “stomach flu,” but Norovirus is not related to viruses that cause the flu. Norovirus was originally called Norwalk virus after Norwalk, Ohio. A 1968 outbreak of the illness in that town led scientists to first isolate and identify the virus, in 1972.
Norovirus usually passes from person to person through the feces (solid body wastes) of infected individuals that contaminate food or drinking water. Outbreaks of illness often occur after people eat at a restaurant where a person infected with the virus has prepared or handled the food. Norovirus can also be found in raw shellfish, such as oysters, in regions where waste containing the virus is dumped in the ocean. Several outbreaks of disease have occurred on cruise ships, where the virus contaminated storage tanks that held water used for drinking and cooking.
Norovirus spreads easily from person to person. Any direct contact with an ill person, such as sharing food, hugging, or kissing, can lead to infection.
Symptoms.
Individuals usually become ill within one to two days after swallowing food or water contaminated with Norovirus. Symptoms include nausea, vomiting, and diarrhea. There may also be fever, chills, headache, or muscle aches. People can become dehydrated if they cannot drink enough liquids to replace those lost through vomiting and diarrhea. In severe cases, hospitalization may be necessary. No drugs or medications are effective against Norovirus, but most people recover from the illness within three days.
Diagnosis.
Medical experts believe that Norovirus is a major cause of foodborne illness in human beings. However, most instances of Norovirus illness go undiagnosed. Scientists can isolate the virus in the feces or vomit of infected people, but most people recover before laboratory tests are conducted to detect the virus.
Prevention.
People can reduce their chances of being infected with Norovirus by washing their hands with soap and warm water after toilet visits and before preparing or eating food. Anyone who thinks he or she may be infected with the virus should not prepare or handle food for other people. People who have recently recovered from Norovirus should wash their hands frequently to prevent passing it to other people. Cooking shellfish thoroughly before eating will reduce the chances of infection from seafood. Raw vegetables and fruits should always be washed thoroughly before being eaten. When visiting areas that may have contaminated water, people should drink only bottled beverages or liquids that have been boiled and avoid drinks with ice cubes.
See also Food poisoning .
