10,000 Yosemite Visitors May Have Been Exposed to Deadly Hantavirus

Up to 10,000 people who stayed in Yosemite National Park between June and August may have been exposed to a deadly, mouse-borne hantavirus


Nearly 4 million people from around the world stay in Yosemite National Park each year, and seventy percent of those visitors stake tents in Yosemite Valley, where Curry Village, a lovely hamlet of “Signature” tents, is located. Friday, the village became less appealing for travelers when park officials released a harrowing statement: Up to 10,000 people who stayed in Yosemite National Park between June and August may have been exposed to a deadly, mouse-borne hantavirus.

The Centers for Disease Control and Prevention says the virus was most likely first transmitted in 91 of the National Park’s tent-style cabins in the Curry Village camping area, where officials found an infestation of deer mice, carriers of the disease. The virus kills one-third of the people it infects. What’s worse: There is no cure.

According to Reuters, U.S. health officials have sounded the alarm worldwide—citizens from 39 countries who stayed in Yosemite’s tent cabins may have been exposed to the rare and deadly disease:

“Four of those known to be infected at Yosemite this summer slept in the insulated tent cabins. One slept elsewhere in Curry Village, located in a valley beneath the iconic Half Dome rock formation, and the sixth case remains under investigation.”

Campers who stayed in the tents this summer risk developing the hantavirus in the next six weeks, the CDC says. The virus begins its work with flu-like symptoms, including headache, fever, muscle aches, shortness of breath and cough, all of which can lead to severe breathing difficulties, then death. Five hundred eighty-seven cases were diagnosed nationwide from 1993 and 2011, meaning thirty-six percent of reported cases are fatal.

There is some hope if the symptoms are detected early enough. Through blood tests, and proper treatment, victims may survive, reports Reuters:

“Early medical attention and diagnosis of hantavirus are critical,” Yosemite superintendent Don Neubacher said in a statement. “We urge anyone who may have been exposed to the infection to see their doctor at the first sign of symptoms and to advise them of the potential of hantavirus.”

The park set up an emergency phone line Tuesday that drew 900 calls its first day, Yosemite spokeswoman Kari Cobb said. The LA Times reports:

“The final guests were moved from the cabins Tuesday, Gediman said. By Friday, all tents had been cleaned and retrofitted to repair gaps in the walls that allowed virus-carrying deer mice to get inside.

Officials are still waiting to see if the efforts are successful at keeping the mice out — if not, Gediman said, the cabins could be moved or closed permanently.”

Yosemite National Park Public Health Service officers are conducting rodent surveys, monitoring deer mouse abundance and virus activity in the parks mouse populations. Call the CDC’s hotline number (404-639-1510) for information about HPS or visit their Hantavirus website.

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