What are Noroviruses?

Noroviruses are a group of viruses that cause an illness some people call the “stomach flu.” They are not related to the flu (influenza). Another name for noroviruses is gastroenteritis.

What are the symptoms?

Vomiting and diarrhea are the most common. Other symptoms may include nausea, stomach cramps, fever, chills, aches, and tiredness.

How soon do symptoms appear?

Symptoms start 1 to 2 days after contact with the virus.

How are noroviruses spread?

Noroviruses are spread through close contact with infected people. For example, noroviruses spread through changing diapers, sharing eating utensils, eating foods or drinking liquids that are contaminated with the virus, or touching infected surfaces or objects and then putting your hands in or near your mouth. Stomach viruses can also spread quickly in group settings like nursing homes, schools, day care centers, and dormitories.

For how long can an infected person spread the virus?

People can spread a stomach virus from the moment they feel sick until at least 3 days after they get better.

How are noroviruses diagnosed?

A health care provider usually makes a diagnosis based on symptoms.

What is the treatment for noroviruses?

There are no specific treatments for noroviruses. Antibiotics do not work. Your doctor may give you medicine to stop the vomiting and diarrhea, but most people get better on their own within 1-2 days. If you have diarrhea or are vomiting, drink plenty of fluids to avoid dehydration (too much fluid loss). If you think you are becoming dehydrated (dry mouth, dry skin, dry eyes), go to a doctor or hospital immediately.

Should an infected person stay home?

Yes. Sick people should stay home until completely recovered, especially food handlers and workers in schools, day care centers, and health care settings.

How can I avoid noroviruses?

  • Wash hands with soap and water often, especially after using the bathroom or changing diapers and before preparing or eating food.
  • Remind children to wash their hands after using the bathroom and before eating. This is especially important while they are ill.
  • Immediately clean up vomit and stool and anything they touch:
    • Disinfect surfaces with a germ-killing cleaner (such as bleach).
    • Wash clothing in hot soapy water.
    • Throw away cleaning rags in sealed plastic bags.
    • Always wash your hands after cleaning.