Several of the cases of Hantavirus have been traced to the cabins at Yosemite. (Wonderlane, Creative Commons)

The virus is mouse-born, and has already killed two people and sickened four more. Four cases have been traced to visitors who stayed in the tent cabins.

Park rangers have been handling thousands of calls from worried summer visitors, and letters and emails have been sent to the thousands of people who reserved space in the cabins between June and August. Visitors have said that they will pay attention to any sign of Hantavirus symptoms in the next few weeks.

Hantavirus is rare and oftentimes fatal. The park is executing efforts to keep the mice out of the cabins, and will tell after time passes if its efforts are successful. There has never been more than one case of the Hantavirus in the same location within one year.

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