August 2012
Safe Food Handling Practices and Sanitation Can Help Prevent Norovirus Norovirus is a very contagious virus that can infect anyone. Noroviruses are a group of viruses previously known as Norwalk-like viruses. You can get it from an infected person, contaminated food or water, or by touching contaminated surfaces. The virus causes gastroenteritis, an inflammation of the stomach and intestines. This infection is often referred to as the “stomach flu� however; it is not related to the flu/influenza that is caused by the influenza virus. It is estimated that noroviruses cause about 21 million illnesses and contribute to about 70,000 hospitalizations and 800 deaths annually. Norovirus is found in the stool (feces) or vomit of infected people. From there it is transferred to food, water or surfaces by the hands of people who have not washed their hands thoroughly after using the restroom. Outbreaks can be caused by contaminated water, such as stored water on cruise ships and swimming pools. Infections can also occur when people consume uncooked contaminated shellfish (clams and oysters) or foods prepared by cooks infected with the virus. Norovirus infections occur year-round, but are more common in the winter. Individuals affected by the norovirus will experience stomach pain, nausea, diarrhea and vomiting. Less common symptoms include low-grade fever or chills, headache and muscle aches. Symptoms usually begin one to two days after ingesting the virus but may appear as early as 12 hours after exposure. The illness normally presents itself suddenly however; some people infected with norovirus have no symptoms at all, but can still pass the virus to others. Symptoms last for 24 to 72 hours. Occasionally infected people may experience milder symptoms for a week or more.