A ground squirrel (Otospermophilus beecheyi) trapped during routine monitoring at the Cedar Groves Group Campground in the 1,897-acre Palomar Mountain State Park in San Diego County has tested positive for the plague, county vector control officials announced Thursday (May 3).

California flea populations are regularly monitored, and control measures are taken as necessary at campgrounds to reduce the potential for human exposure, examiner.com reported. According to environmental health officials, there have been 14 such plague cases reported within Palomar Mountain State Park since June 2008.

“It is not unusual to find plague in our local mountains in the summer months, so campers should always avoid contact with squirrels and their fleas,” said Jack Miller, director of the Department of Environmental Health. “Set up tents away from squirrel burrows, do not feed the squirrels and warn your children not to play with squirrels.”

The heavily forested Palomar Mountain State Park – located off Highway 76 to the northeast of San Diego – provides campers with spectacular views of the Pacific Ocean. Cedar Groves Campground – which is one of a number of camping locations inside the state park – incorporates three individual group camps which are available by reservation only; Group Camp 1: 25 people 10 cars $96 per night, Group Camp 2: 15 people 5 cars $60 per night, and Group Camp 3: 15 people 5 cars $60 per night.


Plague is a bacterial disease of wild rodents that can be transmitted to humans through the bite of infected fleas. There are three forms of plague; bubonic, pneumonic and septicemic which, if left untreated, can prove fatal. Plague was first found in California in 1900 though the last city to have an outbreak was Los Angeles in 1924-1925. To date, there have been no locally acquired human cases of plague reported in San Diego County.

According to the San Diego County website, “outbreaks of the plague tend to occur in the foothills, plateaus and mountains higher than 4,000 feet. It is absent from the southeastern desert region and the Central Valley. Major threats to humans are in the recreational, wilderness and rural parts of the state as well as the suburban foothill area of some large major cities.” In July, 2010 plague closed the Los Alamos Campground in the Angeles National Forest