What is norovirus?

Norovirus is a virus that causes diarrhea and vomiting in people. Some people mistakenly call it "the stomach flu."

What are the symptoms?

Symptoms of norovirus usually start within 12-48 hours after exposure, but can happen as early as 10 hours after exposure. Symptoms include nausea, vomiting, watery diarrhea and stomach cramps. Some people may have a fever, chills, headache and muscle aches. For most people the illness is brief, lasting only a few days (24-60 hours).

How serious is norovirus?

Norovirus is usually not serious, but people may feel very sick. Most people get better within a few days and have no long-lasting health effects from the illness. Sometimes people are unable to drink enough liquids to replace what they lose from vomiting and diarrhea, become dehydrated and need to see a doctor. Usually only the very young, the elderly and persons with weakened immune system experience this complication.

How is norovirus spread?

Noroviruses are highly contagious and spread easily from person to person. The virus is found in the stool and vomit of infected people. People become infected in several ways, including:

  • Direct contact with someone who is infected or taking care of an infected person;
  • Touching surfaces or objects contaminated with norovirus and then putting their hands in their mouths;
  • Eating food or drinking liquids that are contaminated with norovirus; and
  • Inhaling virus release when an infected person vomits.

People who have norovirus are contagious from the moment they begin feeling ill to at least 48 hours after symptoms end.

How is norovirus diagnosed?

Diagnosis is usually based on the person's symptoms. Laboratory testing for norovirus can be helpful when trying to determine the cause of an outbreak (like in a hospital or long-term care facility).

What treatment is available?

Currently, no specific medication or vaccine exist for norovirus, and it can't be treated with antibiotics. Instead:

  • Drink plenty of fluids so you don't become dehydrated;
  • Wash your hands often;
  • Get plenty of rest; and
  • Call your healthcare provider if you have questions or concerns.

Can norovirus be prevented?

You can decrease your chance of becoming ill with norovirus or spreading norovirus to others by:

  • Frequently washing your hands with warm water and soap (especially after using the toilet, changing diapers, before eating and before preparing food);
  • Promptly cleaning then disinfecting contaminated surfaces with household chlorine bleach-based cleaners;
  • Washing soiled clothing and linens with detergent and hot water, then dry thoroughtly in a dryer;
  • Avoiding food or water from sources that may be contaminated; and
  • Not preparing food for others for at least 48 hours after symptoms have ended.

Keep Norovirus at Bay

Beat the bug before it bites! Click the image for a printable infographic.

Noro Virus Infographic_Image



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