Norovirus, or "stomach flu", is a highly contagious virus that spreads easily from person to person. Symptoms include nausea, vomiting, diarrhea, abdominal cramping, and sometimes low-grade fever, chills, headache, muscle ache and fatigue. Symptoms usually begin 24-48 hours after exposure and last for 1-2 days.
Noroviruses are found in the stool and vomit of infected people. The virus is primarily spread by direct contact with an infected person or contact with fecally contaminated food or water. Outbreaks have also occurred from eating undercooked oysters harvested from contaminated waters. In hospitals, the virus can also be transferred from the hands to the mouth via contact with contaminated environmental surfaces and equipment. Outbreaks of norovirus gastroenteritis are common in semi-closed environments such as hospitals, nursing homes, schools and cruise ships.
Anyone can become infected with noroviruses. Because there are many strains of the virus, infection and illness can recur throughout a person's lifetime. People infected with norovirus are contagious from the start of symptoms to at least three days after recovery. Infected persons who work in hospitals, take care of patients or handle food should be restricted from work for three days after symptoms end.
Currently, there is no specific medication or treatment for norovirus. Norovirus cannot be treated with antibiotics. Supportive care, such as getting plenty of rest and drinking fluids to prevent dehydration, is recommended.
Measures to reduce the spread of norovirus include:
In the home setting, the Centers for Disease Control and Prevention (CDC) recommends cleaning surfaces potentially contaminated with norovirus, such as toilets and bathroom surfaces, with bleach-based household cleaners.