Nature: stirring, majestic, full of shit that can kill you.

Public health officials are warning 22,000 visitors to Yosemite National Park that they may have been exposed to the very deadly hantavirus. A third infected person, who visited Yosemite in July, died last week.

Originally, investigators thought only cabins in the Curry Village section of Yosemite had been affected, but the eighth infected person camped at the High Sierra Camp, which meant public health officials had to expand their warning.

The hantavirus is rare: there have been only 602 reported cases since it was discovered in 1993. But with 216 deaths, it has an impressive 36 percent mortality rate.

Hantavirus is mostly carried by deer mice. A 2010 study found that 18 percent of the mice tested in Yosemite had the virus, although transmission is still rare. To contract it, a person has to have been in contact with infected mice feces or urine, which adds an extra level of discomfort to those who get it.

And it basically looks like a flu. The CDC describes the symptoms as—

Fatigue, fever and muscle aches, especially in the large muscle groups — thighs, hips, back and sometimes shoulders ... There may also be headaches, dizziness, chills and abdominal problems, such as nausea, vomiting, diarrhea and abdominal pain.

But within four to ten days, things get more severe, with patients experiencing shortness of breath and coughing as the lungs fill up with fluid.

None of this should deter you from visiting our nation's gorgeous national parks. Just do your best to stay away from filthy rodents.

And if you are feeling extra paranoid, remember there's no shame in being an indoor kid.

[Image via Shutterstock]