Public warned to watch for plague due to rodents

Published Aug. 24, 2017

MARTIS CREEK LAKE, California As a public safety precaution, the U.S. Army Corps of Engineers, under advice from the California Department of Public Health (CDPH), have posted signs alerting visitors to the possibility of chipmunks, ground squirrels, and other rodents being infested with fleas that may carry plague in the Martis Creek Lake Alpine Meadows Campground.


On August 22, CDPH officials will be placing insecticide-treated bait stations throughout Alpine Meadows Campground for flea control.  The treatment will help reduce the number of fleas on rodents and decrease the potential transmission of plague to humans. Health officials are not aware of any human contact with infected rodents or fleas at the campground.


Plague is naturally present in many parts of California, including higher elevation areas of Nevada and Placer Counties and is spread by squirrels, chipmunks and other wild rodents and their fleas. People may get plague if bitten by an infected flea or through close contact with an infected rodent or pet. Plague can be prevented by avoiding contact with wild rodents, and by keeping pets away from rodent burrows. Risk of acquiring plague is very low when precautions are taken.


Symptoms of plague usually show up within two weeks of exposure to an infected animal or flea, and include fever, nausea, weakness and swollen lymph nodes. Plague can be effectively treated with antibiotics if detected early.


Tips to prevent exposure to plague include the following:


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 at 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.



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.


State and local health officials will continue to monitor plague-prone areas. To report a sick or dead rodent or for questions about plague, please contact the Nevada County Environmental Health Department at 530-265-1222, Monday through Friday from 8 a.m. to 5 p.m. For questions about plague surveillance activities, contact CDPH Office of Public Affairs at 916-440-7259. For more information about plague, visit the CDPH website at:



J. Paul Bruton

Release no. 17-022