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Norovirus (Stomach Virus): Facts and Details

What is norovirus?

Norovirus is a contagious disease caused by a group of viruses (caliciviruses). Common names for norovirus in-clude stomach virus, “stomach flu,” or food poisoning. Norovirus is not related to the flu (influenza), which is a respiratory illness caused by the influenza virus.

How common is norovirus?

Norovirus is the leading cause of foodborne illness (food poisoning) in the United States. There are many different norovirus strains, so a person can be ill with norovirus more than once.

How do people become infected?

Norovirus is highly contagious and can spread easily from person to person. Both stool (poop) and vomit are infectious. Ways people become infected include:

What are the signs and symptoms of norovirus?

Symptoms include sudden onset of nausea, vomiting, diar-rhea, and some stomach cramping which may be worse in children. Other symptoms include low-grade fever, chills, headache, muscle aches, and fatigue.

How long can I spread norovirus?

After exposure, symptoms appear in 12 to 48 hours and last about one to two days. People with norovirus are con-tagious from symptom onset until at least two days (up to two weeks) after they recover.

How is norovirus treated?

Norovirus is caused by a virus, so antibiotics won’t work. There is no antiviral medication available for norovirus, but people should drink plenty of fluids to avoid dehydra-tion.

Who is at risk for severe disease?

Anyone can become infected with norovirus, but children less than five years old, people with weakened immune systems, and the elderly are most at risk for se-vere disease.

How can you prevent norovirus?

There is no vaccine for norovirus. Prevent infection by the following methods: