Over 12,000 tourists who stayed at a remote campsite in California's Yosemite National Park are at risk from then deadly hantavirus, officials have warned, following the death of a third holidaymaker.
A West Virginian who visited the park in June has became the third person to die from the virus, and eight cases have been confirmed so far, according to the BBC.
There is no known cure for the virus, which is spread by rodent droppings, and symptoms can take up to six weeks to show, with one third of cases being fatal.
It is carried by rodent faeces, urine and saliva, and can be inhaled by humans when it dries out and mixes with dust.
The disease can also be spread if people eat or touch contaminated products, or if they are bitten by an infected animal.
Yosemite National Park has said it is receiving around 1,000 calls a day to its hantavirus hotline from terrified visitors.
The park has contacted several thousands of groups of visitors warning them to seek medical advice if they experience flu-like symptoms, including headache, fever, shortness of breath, muscle ache and cough.
Severe cases can lead to extreme breathing difficulty and death, but Yosemite says that five individuals of the eight cases linked with the park are now recovering.
The first death was reported in August, and one of those that died was a 37-year-old man from San Francisco Bay.
The outbreak of the virus at Yosemite is thought to have been caused by mice nesting in the insulation of tents at a campsite in the Curry Village area of the reserve.
Read more at the BBC.
Yosemite National Park visitors could have been exposed to deadly virus
Holidaymakers at risk of deadly virus spread by mice
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