SAN FRANCISCO - Yosemite National Park officials extended a hantavirus alert on Thursday to 12,000 more former visitors, warning them of possible exposure to the deadly disease after an eighth case was confirmed in a man who was apparently infected in the park's high country.

The seven other victims, three of whom have died, are all believed to have contracted the rodent-borne virus while staying in double-walled tent-cabins in the popular Curry Village campground in a lower-elevation area of the park.

A previous hantavirus alert had been directed to 10,000 people who had stayed in those 91 tent cabins over the summer, but the latest advisory brings the total number of former park visitors warned of possible exposure to 22,000, Yosemite officials said.

Please LIKE our Facebook page - it makes us stronger