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What is norovirus?germy 5.jpg

Noroviruses are a group of viruses that cause diarrhea, vomiting and stomach pain. Norovirus is often called by other names such as viral gastroenteritis, stomach flu and food poisoning. It is not related to the flu (influenza), which usually causes respiratory illness.

Who gets norovirus?

Anyone can develop this disease. It occurs only in humans and is found worldwide. It is very easy to spread and is very common due to the ease of transmission.

What are the symptoms?

Symptoms usually begin 1 to 2 days after exposure to the virus, but can occur as early as 12 hours after exposure. Common symptoms include nausea, diarrhea, vomiting, and stomach pain. Sometimes people may develop low-grade fever, chills, headache, muscle aches and tiredness. The illness may come on suddenly, and it is possible to have norovirus infection many times. Sometimes people with norovirus have no symptoms at all, but can still pass the infection on to others.

How long does it last?

Most people recover in 1 to 2 days. Sometimes infected people are unable to drink enough fluid to replace what they are losing from diarrhea and vomiting, and can become dehydrated. This is more likely to occur in very young children, the elderly or those with certain other health problems.

How does it spread?

Noroviruses are found in the stool (feces) or vomit of infected people. Noroviruses are transferred to food, water, or surfaces by the hands of infected people who have not washed adequately after using the bathroom.

People become infected with norovirus by:

  • Eating food or drinking liquids contaminated by an infected person.
  • Eating uncooked shellfish that has been harvested from contaminated waters.
  • Touching contaminated surfaces or objects and then touching their mouth or eating without washing their hands first.

What should I do if I have these symptoms?

Drink plenty of fluids so you do not become dehydrated, wash your hands often and contact your healthcare provider if you have any concerns (especially if you do not recover quickly or are at risk for dehydration).

How long can an infected person spread norovirus?

Most people can spread the virus from the time they feel sick until 3 days after they get better. Good handwashing is important to prevent spread to others.

Should I stay home from work or school?

Yes. To prevent spreading the illness to others, a sick person should stay home until he or she has completely recovered and all symptoms have resolved. Under public health regulations, food handlers and healthcare workers must stay out of work for 72 hours after their symptoms have resolved.

How can I prevent norovirus infection?

  • Wash your hands often with soap and warm water, especially:
    • After using the bathroom
    • After changing diapers
    • Before preparing foods
    • Before eating
    • Be sure to wash your hands more often when someone in your household is sick
  • Clean and disinfect surfaces immediately after vomiting or diarrheal accidents
  • Cook food appropriately (especially shellfish)
  • Wash and/or peel fruits and vegetables before eating them
  • Avoid preparing food for others while you have symptoms and for at least 3 days after you recover

Click here for norovirus information from the Centers for Disease Control and Prevention.

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