Yellowstone and Grand Teton National Parks Warn Visitors of An Increase In Illness for Visitors and Employees

The National Park Service is warning travelers that may be planning a visit to Yellowstone or Grand Teton National Park that they should be vigilant about washing their hands due to a spike in sicknesses among visitors so far, according to CNN.

The park service noted "greater than normal reports of gastrointestinal illness" among those visiting the areas of the park in northern Wyoming as well as areas in Montana outside the two parks in a news release on Wednesday.

An incident occurred on June 7 when a tour group visiting Mammoth Hot Springs, an area of the park on the border of Montana and Wyoming, began complaining of stomach and other issues. Park employees who had come into contact with the tour group also reported experiencing similar symptoms within 48 hours.

Tests have indicated that the tour group and employees were suffering from norovirus, which is described by the Centers for Disease Control (CDC) as "a very contagious virus that [can be contracted] from an infected person, contaminated food or water or by touching contaminated surfaces."

There have been approximately 100 additional suspected cases of norovirus among Yellowstone employees and another 50 suspected cases among Grand Tetons employees, according to the National Park Service, who released a press statement on the matter.

Both the park service and businesses that serve visitors are taking precautionary steps against the illness by cleaning and disinfecting public area more frequently. Additionally, any park employees showing signs of infection must be symptom-free for 72 hours before returning to work.

One woman who was among those that became ill posted on the Yellowstone Facebook page, calling it "the worst pain I have ever had." She became ill on June 7.

"I'm going this weekend and will be washing my hands like crazy, not to mention using disinfecting wipes after leaving public areas," another woman wrote. "This sounds like a quick way to ruin a trip, hope everyone is ok!"

Park officials have reached out to all visitors who stayed at the park between mid-June and the end of August at the "signature tent cabins" that became the center of the investigation.

Illnesses have hit the national parks before. Last summer, at least eight visitors to Yosemite National Park contracted Hantavirus pulmonary syndrome, resulting in three deaths. This is a rare but serious condition that can have symptoms that mimic a cold or flu.