Recently, there has been a surge in norovirus epidemics, particularly at schools and on cruise ships. Worse, four hospitals have reported outbreaks in recent weeks. Norovirus clusters are frequently found where people are in close quarters for an extended period of time. It can be traced to contaminated food but also spreads between people in crowded conditions. In fact, only about a quarter of norovirus-caused gastroenteritis comes from food.
Norovirus refers to any of a group of related microbes that attack the stomach and the intestines. Together, they cause 20 million cases of gastroenteritis in the U.S. each year. Norovirus is a common cause of food poisoning, responsible for 58 percent of foodborne illness. Symptoms include diarrhea, nausea and vomiting, and severe stomach cramps. Some people also experience fever and chills, headaches and muscle aches, and fatigue.
While these problems usually clear up after a day or two, gastroenteritis can be serious or even fatal in young or old people, or in people who are already sick with something else or with a chronic condition.
Researchers are working on a vaccine that could help halt future outbreaks. A norovirus vaccine has undergone limited human trials in Arizona. Scientists predict it will be available to the general public, most likely as a nasal spray, in about four to five years.