Norovirus

Norovirus is a virus that causes highly contagious illness. Norovirus illness is often called other names like viral gastroenteritis, stomach flu, or food poisoning.

Symptoms of Norovirus

The most common symptoms are watery diarrhea, explosive projectile vomiting (vomit that shoots out), and stomach pain. Most people get better within 1 to 2 days. Dehydration can be a problem among some people, especially young children, older adults, and people with other illnesses.

How People Get Norovirus

Norovirus is highly contagious, and anyone can get it. You can have the illness more than once.

People with norovirus are contagious from the moment they begin feeling ill. They are still contagious after they recover, lasting anywhere from 3 days to 2 weeks.
Norovirus can survive in the environment for a long time. It can survive freezing or heat up to 140°F. The sources of norovirus are people who are infected (specifically, their poop and vomit), as well as raw or undercooked shellfish.
Norovirus can spread rapidly in closed environments like dormitories, daycare centers, prisons, cruise ships, and nursing homes.

The illness is spread when people:

Have direct contact with an infected person, such as caring for or sharing food, drinks, or eating utensils with an infected person.
Eat or drink something contaminated with norovirus, including pool water, lake water, or shellfish from an unsafe area.
Touch surfaces or objects that are contaminated with norovirus and then place their hand in their mouth or eat something with their hands.

How to Prevent Norovirus Infection

Practice Good Hand Hygiene

Wash your hands carefully with soap and water, especially after using the toilet and changing diapers, and always before eating or preparing food.
Make sure that anybody with diarrhea, especially children, washes their hands carefully and frequently with soap and water.
Alcohol-based hand sanitizers are not a substitute for washing with soap and water.

Take Care in the Kitchen

Wash fruits and vegetables carefully.
Cook oysters and other shellfish thoroughly before eating them.
Do not prepare food for others or share food with anyone if you are sick. People who have norovirus should not prepare food for others while they have symptoms and for 3 days after they recover from their illness.

Clean and Disinfect

Clean and disinfect contaminated surfaces, especially after an episode of vomiting or diarrhea, with a solution of bleach and water. Some recommended strengths are:

1 tablespoon of bleach per gallon of water for stainless steel, utensils, dishes, and washable toys.
1/3 cup of bleach per gallon of water for non-porous surfaces such as tile floors, countertops, sinks, and toilets.
1½ cups of bleach per gallon of water for porous surfaces such as wooden floors.

For more information, see EPA’s Registered Antimicrobial Products Effective Against Norovirus.

Immediately remove and wash clothes or linens that may have vomit or poop:

Handle soiled items carefully, without shaking them, to avoid spreading the virus.
Wash items with detergent at the highest cycle length and then machine dry.

Treatment for Norovirus

There is no vaccine to prevent norovirus infection.

There is no specific drug to treat people with norovirus infection. Rehydration is important – drink plenty of liquids to replace fluid lost through vomiting and diarrhea. In severe cases, intravenous fluids may be needed.