The California Department of Public Health detected plague during a routing testing of a ground squirrel from the San Jacinto Mountains said Riverside County Director of Disease Control Barbara Cole.

The ground squirrel tested positive for exposure to fleas infected with bacteria that can cause plague, Riverside officials said.

“CDPH did confirm recently the presence of plague antibody in the blood of a California ground squirrel from the Fern Basin Campground near Idyllwild,” wrote Ronald Owens, CDPH public affairs officer.

The Fern Basin campground is located about 4 miles north of Idyllwild in the Azalea Trails and Stone Creek Campground Road area. Warning signs have been posted around the campground, according to John Miller, San Bernardino National Forest public affairs officer.

“Riverside County Vector Control ... told forest officials the finding so far was evidence of a past infection, and the risk to visitors is low,” Miller wrote. “They are going to continue to monitor the site and will provide additional direction as to any changes we may need to make in management of the site.”

Cole stressed there is no need to worry, but campers and residents should refrain from touching ground or tree squirrels. Contact between squirrels and pets should also be prevented, she advised.

This is the first positive test for plague since 2002.

For more information, contact Dottie Merki, Environmental Health program chief at (951) 358-5172.

Precautions against ill squirrels, plague
County officials ensured that warning signs are clearly posted and recommend that visitors, hikers and campers follow the precautions to prevent contact with fleas, including:

  • Avoid contact with ground squirrels, tree squirrels and other wild animals.
  • Do not feed or touch wild animals, or touch dead animals.
  • Do not rest or camp near animal burrows.
  • Protect your pets by leaving them at home, or by keeping them on a leash and using flea-control methods.
  • Contact your doctor immediately if you become ill after visiting a known plague area. Symptoms include a sudden onset of fever, chills and tender swollen lymph nodes.