Three squirrels from two local campgrounds have tested positive for plague, the San Diego County Department of Environmental Health said Wednesday.
According to environmental health officials, two plague-positive squirrels were trapped in a routine monitoring at Cedar Grove Campground near Palomar Mountain. The third was trapped at nearby Doane Valley campground.
Officials say it is not unusual to find plague in local mountains. Plague is mainly a disease carried by wild rodents, though it can spread to people through fleas that feed on the blood of an infected rodent and then bite humans.
Last month, a different squirrel captured at Cedar Grove Campground tested positive for plague, making that the first case of plague found locally this year.
With these latest plague-positive squirrels, that number has gone up.
Health officials say hikers and campers should avoid coming into contact with squirrels or their fleas.
Campers should set up their tents away from squirrel burrows and avoid feeding or playing with squirrels.
Those who visit local mountains should always be aware of posted "Plague Warning" signs and follow precautions.
There have been no locally acquired human cases of plague reported in San Diego County. If you become ill within one week of visiting a known plague area, officials say you should immediately contact a doctor. Symptoms include sudden fever, chills and tender, swollen lymph nodes.
For more information about plague surveillance, visit the Vector Control Program website.
Ed.Note: The county originally identified Laguna El Prado Campground east of Alpine as one of the locations affected. Officials later corrected that information. We have updated the article to reflect the correct information.