A second visitor to Yosemite National Park in California was confirmed dead on Monday, after contracting hantavirus while staying in Curry Village. Yosemite officials now say 1,700 past visitors may have been exposed to the rodent-borne disease when they stayed in the cabins at the popular national park.

Rangers are treating the outbreak as a serious concern, distributing brochures to park visitors about hantavirus and the possibility of further harm. All guests checking into the Curry Village cabins are being warned about the possible outbreak.

Hantavirus is an obscure illness spread by rodent feces, urine, and saliva, which is fatal in 30% of all cases. The disease is spread primarily through deer mice, which live at higher elevations and are common in the eastern Sierra of California. There is no known treatment. The disease can incubate for up to six weeks before flu-like symptoms can develop. After two to seven days, many patients have difficulty breathing and can die.

There are 587 documented cases of the disease in the U.S. since 1993, and one-third have been fatal.

Two other people have been confirmed affected, but they are likely to survive.

Curry Village is a popular family-friendly tourist destination, because it is a collection of cabins at the base of Glacier Point which is cost-efficient. The Village has 408 tent cabins, and 91 of those are higher-end, with more amenities.

While officials are saying they don't anticipate finding any more confirmed cases of the disease, 1,700 tourists are on edge. 

If you have questions about hantavirus, officials are urging you to call Yosemite National Park at (209) 372-0822.