JACKSON, Wyo. (CBS/AP) A norovirus outbreak that may have originated at Yellowstone National Park in Wyo. may have affected around 200 people at both Yellowstone and Grand Teton National Park.
About 50 visitors have reported symptoms associated with norovirus, a highly contagious stomach flu that is easily spread by touching an infected person or contaminated surfaces. Up to 150 park employees may have been infected, though not all those cases have been confirmed.
The outbreak is believed to have started with a group of tourists who visited the Mammoth Hot Springs area in Yellowstone on June 7. They complained of stomach flu symptoms and, within 48 hours, employees who work with visitors also reported being sick.
Physician's assistant Michael Takagi told the Jackson Hole Daily that the outbreak is one of the most significant ones he's seen.
The National Park Service issued a June 19 statement urging visitors to northwestern Wyoming to be vigilant about washing their hands, due to "greater-than-normal reports of gastrointestinal illness" after visitors and employees visited medical clinics with symptoms of norovirus.
"It's been almost a decade since we've seen anything on this scale here," Al Nash, a Yellowstone spokesman, told The New York Times.
The National Park Service and all businesses serving park visitors have instituted a variety of safety precautions intended to limit the spread of norovirus. "These include increased cleaning and disinfection of all public areas including stores, gift shops, restaurants, and lodging facilities, and isolation of potentially infected employees until they have been symptom-free for at least 72 hours," according to the statement.
Norovirus is behind more than 20 million causes of gastrointestinal illness in the U.S. each year. About 70,000 people are hospitalized each year from it and 800 die. Young children and the elderly may be impacted more severely.
Anyone can get norovirus, according to the Centers for Disease Control and Prevention. The agency recommends proper hand hygiene by washing your hands with soap and water, especially after using the toilet and always before eating or preparing food. Alcohol-based hand sanitizer can reduce the number of germs on your hands in the absence of running water, but the CDC said hand sanitizer is no substitute for soap and water.
If you're feeling sick with a stomach bug, do not prepare food for others until at least three days after you've recovered. Wash all laundry thoroughly, wearing rubber gloves if handling soiled clothing.
The CDC has more information on norovirus.
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