Palomar Mountain Squirrels Test Positive for Plague

San Diego County officials issued the following news release Wednesday:

Three ground squirrels trapped during routine monitoring on Palomar Mountain have tested positive for plague, County vector control officials said Wednesday. Officials said the squirrels represented a low risk of transmission because their blood tests showed their exposure to the plague bacteria was not recent, and because they did not carry large numbers of the types of fleas that could transmit the disease. Two of the squirrels were trapped at Cedar Grove Campground; the third was trapped at Doane Campground.

Jack Miller, director of the County Department of Environmental Health, said it was not unusual for animals to test positive for plague in the county’s local mountains during summer months. He said the public could take simple steps to protect themselves from possible exposure when camping and visiting parks by avoiding coming into contact with squirrels and the fleas they carry.

“Set up your tents away from squirrel burrows, do not feed the squirrels and warn your children not to play with squirrels,” Miller said.

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 the website at SDVector.com.