Ground Squirrel Tests Positive for Plague

A ground squirrel trapped during routine monitoring at the Cedar Grove Campground on Palomar Mountain has tested positive for plague, County vector control officials announced Thursday.

Environmental health officials said the public could take simple steps to protect themselves from possible exposure when camping and visiting parks.

“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.”

Plague is a bacterial disease of wild rodents that can be transmitted to humans through the bite of infected fleas. To date, there have been no locally acquired human cases of plague reported in San Diego County. Flea populations are monitored, and control measures are taken as necessary at campgrounds to reduce the potential for human exposure. 

Plague Warning signs are posted in all areas where plague has been confirmed.  Visitors, hikers and campers in rural mountain areas should look for these signs and always follow these precautions to prevent contact with the fleas:

  • Avoid contact with ground squirrels, chipmunks, and other wild animals.
  • Do not feed, touch or handle wild animals.
  • Do not rest, camp or sleep near animal burrows in the ground.
  • Protect pets by keeping them on a leash, use flea control, or best of all, leave pets at home.
  • Contact your doctor immediately if you become ill within one week of visiting a known plague area.  Symptoms include a sudden onset of fever, chills and tender swollen lymph nodes. 
  • Do not touch sick or dead animals.

For more information about plague surveillance, call the Vector Control Program at (858) 694-2888 or visit