Norovirus: How you can stay safe


What is norovirus?

Norovirus is a highly contagious viral illness. It is often called by other names, such as viral gastroenteritis or stomach flu. It is also called food poisoning, although it may not always be related to food. Norovirus is not related to the flu (influenza) which is a respiratory illness caused by the influenza virus. Norovirus causes acute gastroenteritis which is an inflammation of the stomach and intestines. Symptoms of norovirus include diarrhea, vomiting, nausea, and stomach pain. Anyone can get norovirus, and they can have the illness multiple times during their lifetime.

How serious is norovirus?

Norovirus can be a serious illness and make people feel extremely ill and vomit or have diarrhea many times a day. Most people get better within one to two days. Norovirus can be very serious among young children, the elderly, and people with other illnesses, and can lead to severe dehydration, hospitalization and even death.

How contagious is norovirus?

Norovirus is highly contagious and can spread quickly from person to person. Outbreaks of infection are common in crowded, closed places such as hospitals or long-term care facilities, daycare centers, schools, hotels, and cruise ships. People with norovirus are contagious from the moment they begin feeling ill to at least three days and perhaps for as long as two weeks after recovery.

How does norovirus spread?

Noroviruses are found in the stool and vomit of infected people, and on infected surfaces that have been touched by ill people. People can become infected by:

  • Eating food or drinking liquids that are contaminated with norovirus.
  • Touching surfaces or objects that are contaminated with norovirus, and then touching their own mouth, nose, or eyes. 
  • Having direct contact with an infected person; for example, by shaking hands, sharing food or eating from the same utensils, or caring for someone who is ill with norovirus infection. 
  • Not washing their hands before preparing food or eating or after using the bathroom or changing diapers.

How do you prevent the spread of norovirus?

  1. Wash your hands often and well. Wash your hands carefully with soap and water, especially before preparing or eating food, using the restroom or changing diapers. Alcohol-based hand sanitizers are not a substitute for washing with soap and water.
  2. Use precautions in the kitchen. Always wash fruits and vegetables, and cook oysters and other shellfish thoroughly before eating them.
  3. Do not prepare food if you are sick. People who are infected with norovirus should not prepare food for others while they have symptoms and for three days after they recover from their illness.
  4. Clean and disinfect contaminated surfaces thoroughly. After an episode of illness, such as vomiting or diarrhea, immediately clean and disinfect contaminated surfaces by using a bleach-based household cleaner as directed on the product label or a 1:10 solution by mixing 1/4 cup of bleach to 2 1/4 cups of water. Bleach is very caustic and emits potentially lethal fumes, so it should never be used full strength; mix in a well-ventilated area and use caution to prevent splashing.
  5. Wash laundry thoroughly. Immediately remove and wash clothing or items that may be contaminated with vomit or fecal matter. Handle soiled items carefully. Wash laundry with detergent for the longest cycle time available and then machine dry.

Is there a treatment for norovirus?

There is no vaccine to prevent infection with norovirus. There is no specific drug available to treat people with norovirus illness. Antibiotics will not help you if you are sick from the virus. This is because antibiotics fight against bacteria, not viruses.

Rehydration is important for infected people—they must drink plenty of liquids to replace fluid lost through vomiting and diarrhea. In some cases, fluid may need to be given intravenously.

Additional resources
CDC—Viral Gastroenteritis: Q&As
CDC—Norovirus: Food Handlers
CDC—Handwashing: Clean hands Save Lives
CDC—Tips for Healthy Cruising


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