Health officials in California are closing a campground at one of America's most popular wilderness destinations, Yosemite National Park, after tests on dead rodents found them to be carrying the plague.
Authorities said the four-day shutdown beginning Monday would allow workers to fumigate rodent burrows for fleas that carry the infectious bacterial disease.
State health officials began examining the park for signs of plague last month when a child from Los Angeles was diagnosed with the disease after visiting the Stanislaus National Forest and camping at the nearby Crane Flat site. That site was shut for four days and treated with an insecticide.
The U.S. National Park Service said the unidentified child, the first reported plague case linked to Yosemite since 1959, is recovering.
In a statement Friday, the park service said the risk to human health remains low. It described the fumigation treatments as an "extremely precautionary health measure" and said the rest of Yosemite would remain open to visitors.
Plague cases are typically linked to chipmunks and squirrels, and experts say fleas can transfer the disease from the rodents to other animals and humans. Early symptoms including chills, high fever, fatigue and swollen lymph nodes. Authorities say the infection can be fatal if not treated in its early stages.
The U.S. Centers for Disease Control and Prevention says 1,006 probable human plague cases have been recorded between 1900 and 2012. More than 80 percent of them were identified as bubonic plague.