Noroviruses are a group of related viruses that can cause gastroenteritis, which is inflammation of the stomach and intestines. Common symptoms of norovirus include cramping, nausea, vomiting, and diarrhea. Some people may also experience low-grade fever, chills, headache, muscle aches, and fatigue. Norovirus is also often referred to as food poisoning or stomach flu.
CDC estimates that Norovirus causes 19 to 21 million illnesses, 56,000 to 71,000 hospitalizations and 570 to 800 deaths each year. Anyone can get infected with norovirus and you can get it more than once. It is estimated that a person will get norovirus about 5 times during their lifetime. Many people usually get sick with norovirus in cooler months, especially from November to April.
Norovirus spreads quickly from person to person, especially in enclosed spaces such as health care facilities, schools, and cruise ships. It is also a major cause of outbreaks in restaurants and catered-meal settings if contaminated food is served. You can get it by:
- Eating food or drinking liquids that are contaminated with norovirus
- Touching surfaces or objects with norovirus on them and then putting your hand or fingers in your mouth
- Having direct contact with a person who is infected with norovirus, for example, when caring for someone with norovirus or sharing foods or eating utensils with them
People with the illness are contagious from the moment they begin feeling sick and for the first few days after they recover. Some people may be contagious for even longer. There is no vaccine to prevent norovirus infection or drug to treat sick people.
You can help protect yourself and others by following these simple tips:
- Practice proper hand hygiene. Wash your hands carefully with soap and water, especially after using the toilet and always before eating or preparing food. If soap and water aren’t available, use an alcohol-based hand sanitizer. These alcohol-based products can help reduce the number of germs on your hands, but they are not a substitute for washing with soap and water.
- Take care in the kitchen. Carefully rinse fruits and vegetables, and cook oysters and other shellfish thoroughly before eating.
- Do not prepare food while infected. People with norovirus illness should not prepare food for others while they have symptoms and for at least 2 days after they recover from their illness.
- Clean and disinfect contaminated surfaces. After throwing up or having diarrhea, immediately clean and disinfect contaminated surfaces using a bleach-based household cleaner as directed on the product label. If no such cleaning product is available, you can use a solution made with 5 tablespoons to 1.5 cups of household bleach per 1 gallon of water.
- Wash laundry thoroughly. Immediately remove and wash clothing or linens that may be contaminated. Handle soiled items carefully—try not to shake them —to avoid spreading virus. If available, wear rubber or disposable gloves while handling soiled clothing or linens and wash your hands after handling. Wash soiled items with detergent at the maximum available cycle length and then machine dry.
For most people norovirus illness is not serious and they get better in 1 to 3 days. But it can be serious in young children, the elderly, and people with other health conditions.