A popular campground at Yosemite National Park in California will be temporarily closed after several dead squirrels were found to be carrying the plague, officials said.
The move comes about a week after a girl who visited the park tested positive for the plague. She was treated and has recovered.
"As an extremely precautionary public health measure, flea treatment will be applied to rodent burrows in Tuolumne Meadows Campground because several dead animals were tested and found to be carrying plague," park officials said in a statement.
The campground will be closed from August 17-21. The park itself will remain open, including all the other campgrounds.
Plague is carried by squirrels, chipmunks and other wild rodents and their fleas.
"By eliminating the fleas, we reduce the risk of human exposure and break the cycle of plague in rodents at the sites," said Karen Smith, the director and state health officer for the California Department of Public Health.
Separately on Friday, two young campers died when a huge tree branch fell on their tent, officials said.
The youths had been staying at the centrally located Upper Pines Campground in Yosemite Valley.
The names, ages and hometowns of the campers were not released.
Yosemite National Park, located in northern California's Sierra Nevada mountains, is the third-most visited of the US's national parks and one of the oldest.
The website of nearby Sequoia and Kings Canyon National Park warns, that "trees and branches have been falling more frequently, possibly due to the drought and beetle damage. Watch for falling trees!" afp