Norovirus (Norwalk Virus)

Noroviruses are the most common cause of acute gastroenteritis (infection of the stomach and intestines) in the United States. Norovirus illness spreads easily and is often called stomach flu or viral gastroenteritis, 

People who are infected can spread it directly to other people, or can contaminate food or drinks they prepare for other people. The virus can also survive on surfaces that have been contaminated with the virus or be spread through contact with an infected person.

Sources	Produce, shellfish, ready-to-eat foods touched by infected food workers (salads, sandwiches, ice, cookies, fruit), or any other foods contaminated with vomit or feces from an infected person
Incubation Period	12-48 hours
Symptoms	Diarrhea, vomiting, nausea,and stomach pain. Diarrhea tends to be watery and non-bloody. Diarrhea is more common in adults and vomiting is more common in children
Duration of Illness	1-3 days. Among young children, old adults, and hospitalized patients, it can last 4-6 days.
What Do I Do?	Drink plenty of fluids and get rest. If you cannot drink enough fluids to prevent dehydration, call your doctor.
How Do I Prevent It?	Wash hands frequently with soap and running water for at least 20 seconds, particularly after using the bathroom and before preparing food. If you work in a restaurant or deli, avoid bare-hand contact with ready-to-eat foods. Clean and disinfect surfaces contaminated by vomiting or diarrhea (use a bleach-based household cleaner as directed on the label). Clean and disinfect food preparation equipment and surfaces. If you are ill with diarrhea or vomiting, do not cook, prepare, or serve food for others. Wash fruits and vegetables and cook oysters and other shellfish thoroughly before eating them. Wash clothing or linens soiled by vomit or fecal matter immediately. Remove the items carefully to avoid spreading the virus. Machine wash and dry.

General Information

Norovirus Infection (National Institute of Allergy and Infections Diseases)
General information on causes, symptoms, treatment, and prevention.

Norovirus (CDC)
General information, including questions and answers, as well as information for food handlers and healthcare facilities.

Norwalk virus family (FDA)
From the Bad Bug Book; provides basic facts, including associated foods, frequency of disease, complications, and target populations.

Facts About Noroviruses on Cruise Ships (CDC)
Find out why norovirus outbreaks are associated with cruise ships.

Norovirus: Facts for Food Handlers (CDC)
How norovirus is spread through foods and tips for preventing its spread.