Infection Prevention and You: What is Norovirus

What is norovirus? 

Norovirus is a serious gastrointestinal illness that causes inflammation of the stomach and/or intestines. This inflammation leads to nausea, vomiting, diarrhea, and abdominal pain. Norovirus is extremely contagious (easy to spread) from one person to another. Norovirus is not related to the flu (influenza), even though it is sometimes called the stomach flu. Anyone can get norovirus, and they can have the illness multiple times during their lifetime. 

Norovirus causes approximately 21 million illnesses each year. It is the leading cause of illness and outbreaks related to food in the United States. Symptoms start between 12 to 48 hours after being exposed and can last anywhere from one to three days. Symptoms include diarrhea, nausea, vomiting, and/or stomach pain. Dehydration is a big concern for people with norovirus, especially in the elderly and the very young, and a major reason for people being hospitalized. People are most contagious when they are actively sick and for the first few days after getting over the illness. 

How serious is norovirus? 

Norovirus is a serious illness that makes people feel extremely ill and vomit or have diarrhea. 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 does norovirus spread? 

It generally spreads when infected food service workers touch food without washing their hands well or at all. Norovirus spreads from: 

• Person-to-person (e.g., shaking hands, sharing food or eating from the same utensils, or caring for someone who is ill with norovirus). 
• Touching contaminated surfaces or objects, and then touching your mouth, nose, and eyes. 
• Eating contaminated food or water. 
• Not washing hands before preparing food or eating, or after using the bathroom or changing diapers. 

 Why is norovirus so contagious? 

Norovirus spreads so easily because it can be in your feces (poop) before you start feeling sick, and it can stay for two weeks or longer after you’re feeling better. Combine that with people not doing a great job of washing their hands and you have big potential for spreading this virus. Norovirus can spread quickly in closed places such as daycares, nursing homes, schools, and cruise ships.

How can you protect yourself from norovirus? 

• 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. 
• Use precautions in the kitchen. Always wash fruits and vegetables and cook food thoroughly before eating. 
• 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. 
• 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. 
• 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 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. 

Hydration is key for infected individuals. They must drink plenty of fluids to replace fluids lost through vomiting and diarrhea. In some cases, hospitalization is required for intravenous fluids (fluids given in your vein). The best thing to do is contact your doctor, treat symptoms (especially dehydration), and stay home. If you suspect you have norovirus, contact your healthcare provider immediately. 

 Provided by the Association for Professionals in Infection Control and Epidemiology