Hikers, backpackers came down with gastrointestinal illness for 24 to 48 hours.
YOSEMITE NATIONAL PARK -- Park officials said Wednesday that they haven't seen new cases of a gastrointestinal illness that sickened hikers and hospitality employees in the Tuolumne Meadows area in the past two weeks.
About 30 people came down with symptoms consistent with the norovirus infection at the Tuolumne Meadows Lodge and High Sierra camps in the area, said Shane Sims, a specialist in the safety office at Yosemite National Park.
The lodge, at the 8,775-foot elevation, serves as a base camp for day hikers and backpackers. Park rangers began receiving illness reports the weekend of July 12-13, and the cases tapered off last week.
About five hikers with severe symptoms were airlifted from the High Sierra camps, Sims said. Of the six people known to have sought medical attention, all were released from care, officials said.
"Many of the people who were ill were traveling in tight groups, so it was easy for the illness to spread in those groups," Sims said. "People shouldn't fear coming into the park. It appears to be under control."
Experts with the National Parks Service Office of Public Health concluded it was norovirus infection, a common intestinal illness, based on one person testing positive and symptoms that included low-grade fever, nausea, vomiting and diarrhea.
The illness comes on quickly and goes away in 24 to 48 hours. The highly contagious virus can be spread through contaminated food, water or fecal matter. But park officials said they found no evidence that meals served at the lodge or the camps triggered the outbreak.
It's also spread by person-to-person contact and could easily have been brought by any of the thousands of people who visit the park each day, officials said. Sims noted there have been other norovirus outbreaks this summer in Mariposa County.
The Park Service was assisted in responding to the outbreak by the public health departments in Tuolumne, Mariposa and Mono counties.
The hiker camps are particularly vulnerable to the spread of norovirus illness, because people enjoying the outdoors aren't always careful about hygiene, Sims said.
To try to contain the outbreak, the Delaware North Companies, which runs the concessions in Yosemite, used bleach solution to disinfect countertops and tables in the lodge, cleaned bathrooms and scrubbed rooms in which people had been sick. About eight concession employees were among those who became ill.
Health officials also talked with the concession service about taking precautions at the food outlets in Yosemite Village, said Dr. David Wong, an epidemiologist with the National Park Service public health office. For example, any food workers who become ill should not return to work until free of symptoms for 72 hours.
Wong said containing the norovirus is difficult because it can live on surfaces for several days.
"We like to compare the norovirus to Kobe Bryant," he said. "We are not going to stop it. We can just hope to contain it."
E-mail story
Printer friendly page
Subscribe to Print
