Two confirmed cases of norovirus were reported Thursday by officials at Yosemite National Park as at least 170 people have now fallen ill with gastrointestinal issues since visiting the park this month.

Officials issued a statement confirming that two people have contracted the extremely contagious virus after spending time in Yosemite Valley on and around the first week of January.

YOSEMITE NATIONAL PARK VISITORS HIT WITH GASTROINTESTINAL ILLNESS PROMPTING ‘EXTENSIVE CLEAN-UP’: REPORT

According to the Centers for Disease Control and Prevention, norovirus can be transmitted through contaminated food, surfaces or objects, or by coming in direct contact with someone who has already been infected. Symptoms include diarrhea, nausea and vomiting.

Officials said in all, 170 people have reported having gastrointestinal issues and, while only two cases have been confirmed, the “overwhelming majority” are “consistent with norovirus.”

Both park visitors and employees are among the people who have fallen ill.

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“Yosemite National Park officials and medical professionals with the National Park Service Office of Public Health (OPH) are continuing to investigate the circumstances surrounding the illness and are continuing to conduct interviews with affected people,” the statement read.

The source of the contamination was not revealed but a report from the San Francisco Chronicle cited park officials who said an “extensive clean-up and disinfection” operation has begun in the park’s many food establishments, which include restaurants, snack stands and hotels.

This includes the famous Ahwahnee Hotel restaurant which was recently downgraded by AAA from its four-diamond rating to three diamonds.

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Michael Bennett, 69, and his partner, Luke Lowery, 60, told the Chronicle that they stayed at the hotel on Jan. 4 and became “violently ill” on their way home.

“It’s kind of disgusting to think that somebody who didn’t wash their hands may have passed on the virus,” Bennett said.