Four people have exhibited Hantavirus Pulmonary Syndrome after staying in insulated tent cabins in Curry Village over the last several months.
Officials at Yosemite National Park say they updated hantavirus guidelines in April, before any of the four people who have contracted the illness came to the park.
“That entailed going through and reviewing how often people are getting training and how they are getting training,” park ranger Jana McCabe said. “Things like ‘Is it enough just to train the people who are cleaning the rooms or do other people need to be trained?’”
The first-ever recorded deaths are still baffling and officials are unsure what to blame.
Two have died as a result of the illness — which is contracted when an individual inhales dust particles that have been in contact with urine, feces or saliva of rodents carrying the virus. Symptoms include fever, chills, aches or a cough.
Anyone who stayed in Yosemite from mid-June to August who experiences these symptoms should see their doctor immediately and let them know about the possible exposure. About 1,700 visitors may have been exposed.
An estimated 30 percent of hantavirus cases are fatal.
“This is very unusual, it’s a very rare disease,” McCabe said. “We don’t know if there’s something in the environment that has changed or that is contributing to this.”
The deaths are the first-ever recorded from exposure in Yosemite, though there were two cases, in 2000 and 2010, where the individuals recovered.
McCabe said hantavirus can be found all across the United States, as an estimated 20 percent of deer and mice carry the virus.
She advised that before inhabiting an area that has experienced rodent activity, you should spray the entire area with a 10 percent solution of bleach and water or other disinfectant and to wait 15 minutes before wiping it down.
“If you find rodents at your home, take it seriously,” McCabe said.
McCabe said that the park is currently investigating the issue and trying to find an explanation for the outbreak.