Squirrel Found to Be Infected With Plague : Health: Animal is caught at Cuyamaca Rancho State Park, where county launches a flea-eradication program.

Health officials dusted animal burrows in Cuyamaca Rancho State Park with insecticide Thursday after a squirrel was found to be infected with bubonic plague.

Health officials immediately launched a program to wipe out fleas in the popular Paso Picacho Campground, where the infected squirrel was found. On Thursday, they began dusting squirrel burrows around the 85 campground sites with insecticide.

The squirrel was captured in May, but test results, usually available within six weeks, took three months because budget cuts forced a federal agency to pass the task to the state.

Bubonic plague, which ravaged Western Europe in the 14th Century, is deadly if it goes untreated but is readily cured when diagnosed.

The plague can be carried by fleas from infected animals to humans. No such cases have ever been reported in San Diego County, where a mountain lion was found to be infected in 1987 and three dogs in 1982.

“If we can keep the flea population down, we are OK,” said Gary Stephany, deputy director of the county’s environmental health services. “It’s probably not a large (public health) risk; that’s why we are allowing campers to camp in this area . . . If people just don’t get near the squirrels, then the chances of getting the disease are probably slim.”

In a routine surveillance program under way for the past year, local health authorities have tested 10 areas in the county each month, looking for signs of plague. This week, they learned that a ground squirrel snared May 16 from the Paso Picacho campground was infected.

The test results on the squirrel, which was released back into the wild, took longer than the usual four to six weeks because, for budgetary reasons, health officials were switching from a federal testing program, run by the Centers for Disease Control, to a state-run program, said Minoo Madon, a public health biologist with the state health department.

In California, cases of plague-infected animals are not unusual. Last year, 20 counties reported infected animals, Madon said. The disease is known to infect wild animals, including rats, squirrels, coyotes, skunks, badgers, raccoons, bobcats, foxes and bears.

So far this year, the plague has been discovered in eight counties: San Diego, Kern, Pumas, Sierra, Modoc, Monterey, Mono and Siskiyou. Earlier this month, the Plumas-Eureka State Park in Plumas County was temporarily closed after two chipmunk deaths were linked to the plague.

Fourteen of the state’s 30 confirmed human victims since 1970 contracted the disease after camping or hiking, Madon said.

California’s most recent human cases of the plague occurred in 1988, when two individuals were treated and recovered. But earlier this year, a 12-year-old Nevada boy contracted the disease after going squirrel hunting with his father 4 miles from the California-Nevada border, Madon said. The boy’s father, a doctor, immediately recognized the symptoms and sought treatment for his son.

After health authorities learned of the infected squirrel in the popular San Diego park, they rushed to prevent the spread of the disease. Experts say that killing the fleas, rather than the infected animals, is the best way to halt transmission. If the animals are killed, the fleas carrying the disease will simply hop off their dead host, seeking another blood source.

“The fleas have to be killed to stop the disease,” Madon said. “The plague is in the area; it is existing there and to what extent, we don’t know. There is a potential danger.”

Janet Ortiz, a vector surveillance and control manager with San Diego county’s Department of Health Services, said officials considered closing the campground but decided the health hazard could be avoided if campers were warned and heeded those warnings.

As a result, signs warning of plague in the area will be posted throughout the campground, and park visitors will be advised to stay away from wild animals.

People should see their doctor if within 10 days of being outdoors they suffer symptoms such as high fever, chills, headache, muscle aches and general malaise.

So far, health officials have used flea insecticide at only one campground. But in the weeks ahead, they will continue surveillance of 10 areas. At these areas, workers trap California ground squirrels and wood rats, or neotoma rats. The rodents are knocked out with anesthesia while health workers comb and collect their fleas. The fleas, as well as blood samples, are dispatched to state officials for testing.

Test results are expected to be available within six weeks.

The areas that are tested include Lake Murray, Palomar Mountain Observatory campground, Los Penasquitos Canyon, Lake Morena, Lake Sutherland, Loveland Reservoir, El Prado and Lake Wohlford.

Plague Detected A squirrel infected with wild rodent plague was tested during a rountine surveillance effort by the county Department of Health Services. The squirrel was found at Paso Picacho Campground in Cuyamaca Rancho State Park. Plague can be carried by fleas from infected animals to humans, but that has never happened in San Diego County. Steps to follow to avoid the disease Do not camp, rest or sleep near animal burrows-and AVOID FLEAS. Leave pets at home when you go camping, or protect them with flea powder. See a physician if you become ill within a week of your park visit. Plague is curable when diagnosed early. Source: San Diego County Dept. of Health Services.