Pathogen of the Month
August pathogen of the month:
The most common cause of gastroenteritis
What is it?
Norovirus is a highly contagious virus known for its tendency to spread quickly in densely populated areas, as well as through contaminated food. Since it has a reputation for moving freely in areas with large numbers of confined people, it is informally known as a “cruise ship virus,” although it is also common in college dorms and restaurants. However, it is also known to be able to spread quickly via water – in such settings as swimming pools, making it a particular threat in summer. Symptoms include vomiting, diarrhea, and other gastrointestinal symptoms. Norovirus can live in water for several months or possibly even years, the Centers for Disease Control has said -- and lakes and ponds can pose a particular risk, since they're not treated with germ-killing chlorine.
The Centers for Disease control estimates that norovirus causes 19 to 21 million cases of acute gastroenteritis annually, contributing to as many as 71,000 hospitalizations and up to 800 deaths in the United States alone. The case fatality rate worldwide is about 7 persons per 100,000.
What is the current status?
Two recent outbreaks in the United States have thrust norovirus into the news. A July outbreak in Maine sickened nearly 100 people who visited a beach and swam in a lake in the town of Bridgton or had contact with others who had done so. Several people became ill after caring for someone who'd been at that beach and got sick -- even though they hadn't been to the beach themselves. That makes sense, say health officials, since norovirus can also spread through direct contact with infected people.
Also in July, a food court illness that sickened 350 people in Kentucky was identified as norovirus. Citing a Lexington-Fayette County Health Department release, the Lexington Herald-Leader reported that test results from those who had gone to the Fayette Mall food court were consistently positive for the very contagious virus.
How serious can it be?
The illness, which is often characterized as “food poisoning” or “stomach flu,” is not usually serious. There is no treatment, but most people get better within one to 2 days.
Even so, persons with a norovirus illness should drink plenty of liquids to replace fluid lost from vomiting and diarrhea. This will help prevent dehydration, which can lead to serious problems. Severe dehydration may require hospitalization for treatment with fluids given through your vein (intravenous or IV fluids).
Watch for signs of dehydration in children who have norovirus illness. Children who are dehydrated may cry with few or no tears and be unusually sleepy or fussy.
The Centers for Disease Control recommends several common-sense steps designed to reduce the risk of being affected by a norovirus. These steps include practicing proper hand-washing, the safe handling and preparation of food, cleaning and disinfecting surfaces and thorough washing of laundry. It also emphasizes that those who are showing symptoms of norovirus should not engage in the preparation of food for others.
- - - - - - -
Sources: Seattle Pierce County Health Department; oie.int; Lexington Herald-Leader; Centers for Disease Control.