A new strain of norovirus called GII.4 Sydney was the leading cause of norovirus outbreaks in the United States from September to December 2012, according to a study published in Morbidity and Mortality Weekly Report released today by the Centers for Disease Control and Prevention. Norovirus is very contagious. In the United States, norovirus is the number one cause of acute gastroenteritis, which leads to diarrhea and vomiting. Each year, more than 21 million people in the United States get infected and develop acute gastroenteritis; approximately 800 die. Young children and elderly adults have the highest risk for severe illness.
The CDC: Norovirus website (http://1.usa.gov/WZhZDL) contains information for food handlers, health care providers, and public health professionals and the MedlinePlus: Norovirus Infections website (http://1.usa.gov/XtCSXo) contains information for public on the norovirus.