LOS ANGELES, CA

Some 10,000 people who stayed in tent cabins at Yosemite National Park over the summer may be at risk for the deadly rodent-borne hantavirus, the U.S. Centers for Disease Control and Prevention said in a health advisory on Friday.

The advisory urges lab testing of patients with symptoms consistent with the lung disease, hantavirus pulmonary syndrome, and recommends that doctors notify state health departments when it is found.

“An estimated 10,000 persons stayed in the ’Signature Tent Cabins’ from June 10 through August 24, 2012,” the CDC said in the advisory. “People who stayed in the tents between June 10 and August 24 may be at risk of developing HPS in the next 6 weeks.”

Two men have died from hantavirus linked to the Yosemite outbreak and four other people were sickened but survived, California health officials have said.

Most of the victims were believed to have contracted the virus while staying in tent-style cabins this summer in a popular Yosemite camping area called Curry Village.

Park officials earlier this week shut down 91 insulated tent cabins after finding deer mice, which carry the disease and can burrow through pencil-sized holes, nesting between the double walls of the structures.

Park authorities have already notified 2,900 parties of visitors who rented the tent cabins from June through August who they may have been exposed to hantavirus.

Nearly 4 million people visit Yosemite each year, attracted to the park’s dramatic scenery and hiking trails. Roughly 70 percent of those visitors congregate in Yosemite Valley, where Curry Village is located.

Hantavirus is carried in rodent feces, urine and saliva, which dries out and mixes with dust that can be inhaled by humans, especially in small, confined spaces with poor ventilation.

People can also be infected by eating contaminated food, touching contaminated surfaces or being bitten by infected rodents.

The virus starts out causing flu-like symptoms, including headache, fever, muscle ache, shortness of breath and cough. Initial symptoms may appear up to six weeks after exposure and can lead to severe breathing difficulties and death.

Although there is no cure for hantavirus, treatment after early detection through blood tests can save lives. The virus, which has never been known to be transmitted between humans, kills 38 percent of those it infects.