A disturbing virus has been making its way through Yosemite visitors this summer with the help of mice, carriers of the hantavirus. Officials say that the 10,000 people who stayed in Curry Village from June through August could be at risk for this deadly virus, which can progress to the fatal Hantavirus Syndrome (HPS). There have been 602 hantavirus cases nationally since the virus was first identified in 1993 and about 36% (216) have died. Statistics reveal that in 2011, there were 24 cases of the virus which resulted in 12 deaths. Since most victims at the time were exposed at higher elevations, one theory about the outbreak of the hantavirus in Yosemite is that the climate change is leading the mice to move to lower elevations.

Mice and rats can spread the virus among themselves. It is estimated that up to 20 percent of all deer mice carry the virus; even so, it is not harmful to them. In 2010, 18 percent of the deer mice in Yosemite tested positive for hantavirus. It is passed down to humans from droppings, urine, saliva, and blood of infected animals. Most people get it by inhaling contaminated dust, but hantavirus cannot spread from person to person.

The illness can take six weeks to develop before organ failure. The first symptoms are the same as the flu. This includes fever, fatigue, headaches, nausea and muscle aches: symptoms that appear in every person who developed HPS. In the later stages of the illness, the infected begin to experience coughing and shortness of breath, which rapidly worsens. These patients must be hospitalized, but there is no specific treatment for hantavirus infection.

So far, seven confirmed cases of disease have been linked to Yosemite. These cases are rare because there has never been more than one case in the same area within the same year. The first hantavirus case was reported August 16. A West Virginian is the third person to die so far, and laboratory results have confirmed that the victim died due to HPS. The doctors say the victim had not visited the park since June, but no other details were given. The other deaths occurred in California and Pennsylvania, six of which involved people that had stayed in the cabins in Curry Village, while the last case involved a person who stayed in the High Sierra Camps in different parts of Yosemite.

In order to prevent other people from getting infected, health officials have cleared the tents so that they can be repaired.  This will ensure that mice are not able to penetrate through the gaps in the walls and infect others with this virus. The park has sent warning notices to more than 20,000 people who stayed or have reservations at the park. Many people have already called a hotline set up to answer questions about the virus.  “We want to make sure that visitors have clear information about this rare virus and understand the importance of early medical care. We continue to work closely with state and national public health officials, and we urge visitors who may have been exposed to hantavirus to seek medical attention at the first sign of symptoms,”  said Yosemite Superintendent Don Neubacher.

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“Hantavirus .” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 14 September 2012. Web. 16 Sep 2012.

“Hantavirus FAQ:Yosemite Deaths Raise Questions About Hantavirus Pulmonary Syndrome.” WebMD. WebDC, 2012. Web. 16 Sep 2012. <http://www.webmd.com/news/20120829/hantavirus-faq?page=2>.

Jones, Carolyn. “3rd Yosemite visitor dies of hantavirus.” SFGate. San Francisco Chronicle, 6 September 2012. Web. 16 Sep 2012. <http://www.sfgate.com/default/article/3rd-Yosemite-visitor-dies-of-hantavirus-3846079.php>.[/spoiler]