El Dorado County environmental health officials are urging residents and visitors to take precautions after a chipmunk found in the Lake Tahoe Basin last week tested presumptive positive for the bacteria that causes the plague.

The test results for the chipmunk found at the U.S. Forest Service's Taylor Creek Visitor Center led Dr. Bob Hartman, the county's interim public health officer, to warn that the Taylor Creek Recreation Area may have an elevated plague risk. Fall visitors to area picnic spots and campgrounds, as well as area residents, are advised to take measures to protect themselves from the disease, which is transmitted by infected fleas.

"Individuals can greatly reduce their risk of becoming infected with plague by taking simple precautions, including avoiding contact with wild rodents and their fleas," Hartman said in a written statement. "Do not feed rodents in picnic or campground areas and never handle sick or dead rodents. Also, leave your pets at home when visiting areas with elevated plague risk."

Plague is a rare but highly infectious bacterial disease that is spread by squirrels, chipmunks and other wild rodents and their fleas. People may be exposed to plague through an infected flea bite, handling an infected rodent, or exposure to an infected pet, especially a sick cat, according to a county news release.

Early symptoms of plague include high fever, chills, nausea, weakness and swollen lymph nodes in the neck, armpit or groin. Individuals who develop these symptoms within two weeks of possible exposure should seek immediate medical attention and inform the physician that they have been in a plague endemic area. Plague is curable in its early stages with prompt diagnosis and proper treatment but may be fatal if not treated early.

If a pet becomes ill after visiting an area, owners are advised to take it to a veterinarian and inform the vet that the pet has been in an area where rodents have plague.

The U.S. Forest Service is working with El Dorado County and the California Department of Public Health to educate the public about the disease. State and local health officials regularly monitor plague-prone areas. To assess the public risk, additional rodent surveillance will be done in the area this week by state health personnel with assistance from El Dorado County Environmental Health Management and Vector Control.

People are advised to: • Report any sick or dead animals to forest, campground or local health officials. • Avoid walking, hiking or camping near rodent burrows. • Wear long pants tucked into boot tops to reduce exposure to fleas. • Apply insect repellent containing DEET on socks and trouser cuffs. • Keep wild rodents out of homes, trailers and outbuildings. • For protection of pets, keep pets leashed and away from dead rodents.

To report a sick or dead rodent, call the El Dorado County Vector Control at (530) 573-3197.

For more information on the plague in California, click on http://www.cdph.ca.gov/healthinfo/discond/Pages/Plague.aspx.

© Copyright The Sacramento Bee. All rights reserved.

• Read more articles by Cathy Locke

Order Reprint