Los Angeles County Department of Public Health and U.S. Forestry Service officials have closed the Broken Blade, Twisted Arrow, and Pima Loops of the Table Mountain Campgrounds in the Angeles National Forest after tests confirmed that one ground squirrel trapped on July 16, 2013 during routine surveillance activities tested positive on July 23, 2013 for plague. The sites were officially closed at 1:00 p.m. today, and will be closed for at least 7 days. Campers at the site have been notified of the closure by Forest Service officials. The campgrounds and recreational areas are located near Wrightwood. In coordination with the Los Angeles County Department of Agriculture/Weights and Measures, the squirrel burrows in the area will be dusted for fleas. Further testing of squirrels will be done before the area is re-opened to the public.

“Plague is a bacterial infection that can be transmitted to humans through the bites of infected fleas, which is why we close affected campgrounds and recreational areas as a precaution while preventive measures are taken to control the flea population,” said Jonathan E. Fielding, M.D., M.P.H., Director of Public Health and Health Officer. “It is important for the public to know that there have only been four cases of human plague in Los Angeles County residents since 1984, none of which were fatal.”

Plague has been known to reside in the ground squirrels population in the San Gabriel Mountains. Previous routine surveillance identified one plague-positive ground squirrel in 2010 from the Los Alamos campgrounds in Gorman; one in 2007 and two in 1996 from the Stoneyvale Picnic Area near La Cañada/Flintridge; and one plague- positive ground squirrel from an adjacent campground in Vogel Flats in 1995.

Transmission of plague through flea bites causes bubonic plague, with symptoms including enlargement of lymph glands (buboes) near the flea bite and rapid onset of fever and chills. Untreated bubonic plague can progress to infection of the blood, or rarely, the lungs, causing pneumonic plague. All forms of the disease can be fatal if not treated; however, most patients respond well to antibiotic therapy.

Individuals visiting recreational areas near the Broken Blade, Twisted Arrow, and Pima Loops of the Table Mountain Campgrounds need to take certain precautions to avoid contact with wild animals that could be carrying plague- positive fleas. Visitors to recreational areas should not feed wild animals, not leave edible trash out where wild animals can get to it, avoid camping or picnicking in the immediate vicinity of ground squirrel burrows, and should avoid taking pets into areas where they could be exposed to fleas. If you must take your pet into areas with fleas, please ensure your pet has appropriate flea control and vaccinations, as recommended by a veterinarian.

“Protection with an insect repellant containing DEET is also recommended for persons visiting the Angeles National Forest and engaging in outside recreational activities in other areas of LA County,” said Dr. Fielding. Insect repellant can help protect people against fleas, mosquitoes, and ticks. Products containing DEET are not safe for use on pets.”

Members of the public who see dead ground squirrels in recreational areas, or who want more information about precautions should contact the LA County Department of Public Health, Vector Management Program at (626) 430-5450.