The flea that was tested was taken from a chipmunk at the Fallen Leaf Campground in the Lake Tahoe area.
Officials from the Forest Service have posted warning signs throughout the area and have issued a list of tips for visitors to keep themselves safe:
- Do not feed squirrels, chipmunks or other wild rodents.
- Never touch sick, injured or dead rodents.
- Do not camp, sleep or rest near animal burrows or areas where dead rodents are observed.
- Look for and heed posted warning signs.
- Wear long pants tucked into boot tops and spray insect repellent containing DEET on socks and pant cuffs to reduce exposure to fleas.
- Leave pets home if possible; otherwise keep pets on a leash. Do not allow pets to approach sick or dead rodents or explore rodent burrows. Protect pets with flea control products.
- Pet cats are highly susceptible to plague and can pose a direct threat to humans. Keep cats away from rodents. Consult a veterinarian if your cat becomes sick after being in contact with rodents.
- If you get sick after being in an area where plague is known to occur, consult a physician and tell them you may have been exposed to plague.
Symptoms of the plague typically show up within two weeks of exposure, and include fever, nausea, weakness, and swollen lymph nodes.
Last year, a California ground squirrel at the Tallac Historic Site tested positive for plague, as well as two humans who were infected by rodents in Yosemite valley. They were the first humans in the state to contract the antibodies since 2006.
Officials have said that they are continuously monitoring the situation in plague-prone areas.