2013-02-13 / Health

New Strain of Norovirus

by Wayne Coachman UGA/Early Co. Cooperative Extension

Many people may not realize that norovirus, often referred to as “food poisoning” or “stomach flu,” is the leading cause of illness from contaminated foods in the United States. While this illness typically does not make news headlines (unless there is an outbreak on a cruise ship), you may have noticed it is currently receiving a lot of media attention. The reason for this heightened awareness is that, in 2012, a new strain of norovirus was detected in Australia. It is called GII.4 Sydney. While all strains of norovirus are highly contagious, GII.4 Sydney appears to be particularly easy to spread. It is not yet known whether the new strain will cause more norovirus illness than in other years. However, it is an opportunity to remind food service workers about the importance of proper hand hygiene and not working while experiencing vomiting or diarrhea.

Food handlers who are sick with norovirus can easily spread the illness person to person or by contaminating food and drink they touch. In fact, people with norovirus are not only contagious while they are experiencing symptoms but also during the first three days after recovery. Therefore, to protect spreading this illness, it is critical that food service workers follow the exclude/restrict health policies of their establishment while they are experiencing symptoms and for three days thereafter. Of course, appropriate hand hygiene is critical for prevention of norovirus infection and for controlling transmission. Yet, be advised that the efficacy of alcoholbased and other hand sanitizers against norovirus remains controversial; hence, anyone handling food should always wash their hands with warm, running water and soap.

Anyone who works in the food service industry needs to know about norovirus. For the sake of public health, food service workers must understand and appreciate the importance of not handling food while sick and always practicing scrupulous hand hygiene.

The links below can and should be accessed for additional information. Foods commonly involved in outbreaks are leafy greens (such as lettuce), fresh fruits, shellfish (such as oysters). But, any food served raw or handled after being cooked can get contaminated.

Typical symptoms of norovirus include diarrhea, throwing up, nausea, and stomach pain. Other symptoms can include fever, headache, and body aches. Infected people can feel extremely ill and throw up and/ or have many diarrheal episodes a day. Dehydration can occur, especially in young children, older adults, and people with other illnesses. Most people with norovirus illness get better within one to three days. (There is no vaccine or drug treatment at this time.)

Remember that everyone whether in food service or not should also practice strict hygiene and safe food handling practices to avoid the spread of norovirus.

•Wash hands often and thoroughly with soap and water; always wash after using the toilet or changing diapers and before eating or preparing food.

•Rinse fresh fruits and vegetables before eating.

•Norovirus can survive low cooking temperatures or low temperature reheating. For example, be sure to cook seafood (often lightly cooked or eaten raw) to at least 140 degrees F.

•Wash dirty clothes and linens promptly; disinfect surfaces with a bleach-based sanitizer.

•When you are sick, do not prepare food or care for others; wait three days after symptoms disappear. Wash hands often even after recovery.


1. Centers for Disease Control and Prevention. Prevent the spread of norovirus. Internet: http://m.cdc.gov/en/Features/norovirus (accessed 29 January 2013)

2. Centers for Disease Control and Prevention. Norovirus for food handlers. Internet: http://www.cdc.gov/norovirus/food-handlers/work-with-food.html. (accessed 29 January 2013)

3. Centers for Disease Control and Prevention. Norovirus site. Internet: http://www.cdc.gov/norovirus/about/index.html (accessed 29 January 2013).

Released by Elizabeth L. Andress, Extension Food Safety Specialist, January 29, 2013.

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