Tracking Bubonic Plague : Health: The state tests rodents in wilderness areas. Each year the effort finds the disease in nearly every county in California.

Covering himself head-to-toe with bug repellent, Randy Smith dons a pair of rubber surgical gloves, adds a pair of thick work gloves and begins preparing a syringe for Thursday morning’s first blood test of a California ground squirrel.

The precautions are necessary, Smith said, to ward off infection should any of the animals trapped and tested in a campground north of Ojai turn out to be carriers of bubonic plague.

Although widely thought of as the scourge of the Middle Ages, the plague turns up during testing each year in nearly every county in California.

Over the years, the flea-borne bacterial disease has been passed to humans and has even caused several deaths, most recently the 1984 death of a Kern County man who caught the plague from his cat.

Two human cases of bubonic plague have been reported this year, said Chuck Myers, a state environmental manager responsible for the control of wildlife-spread disease in Southern California. Like many bacterial infections, bubonic plague starts with a high fever, malaise, nausea and vomiting.

If not treated quickly, it can lead to the growth of buboes, or large balls, on the lymph nodes as the immune system fights the disease. Within days, it can bring on death.

This year, some rodents tested positive for bubonic plague in numerous wilderness areas of the state, including Frazier Park on the border between Ventura and Kern counties.

Smith, a Ventura County environmental health specialist, has been conducting plague surveillance in Frazier Park, along with other wilderness areas in the Los Padres National Forest and elsewhere for years. “What we want to try to do is catch it before the campgrounds are full of summer people,” he said during Thursday’s blood tests.

To find out if plague is being passed by fleas from wild mice to ground squirrels and other rodents, Smith and colleagues lay traps for the animals, take blood samples and collect fleas for future study.

Most of the seasonal testing is done in backcountry campsites where contact between larger rodents and humans is likely. One such area is Pine Mountain Recreation Area, a hilly, wooded campground about an hour’s drive north of Ojai.

“This area is a place where there’s a lot of interaction between humans and the rodent population,” Smith said.

Smith and fellow environmental health specialist Dan McCann laid 50 traps baited with rolled oats and apple slices earlier this week throughout the campground. The traps are put in areas that show signs of rodent life, such as burrows, droppings or wooden nests, McCann said.

A tree near each trap is marked with pink fluorescent surveying tape, “so we don’t forget any traps or lose any,” McCann said.

Later, Smith and McCann seek out the pink markers and their corresponding traps hoping to find at least one representative of each species implicated in spreading the plague. Often, their work involves climbing up dirt ridges or working their way into heavy brush where the traps have been laid.

On Thursday, they are somewhat unlucky. Only six of the 50 traps contain ground squirrels, a key link in the plague chain, and five other traps have closed on kangaroo rats, which are released. “We don’t bleed those,” Smith said. “They haven’t been implicated in the plague cycle.”

There are no wild rats, chipmunks or wood rats--all of which are thought to spread bubonic plague. Compounding the bad luck, two of the six squirrels managed to escape before the testing.

“That’s par for the course,” Smith said as one ground squirrel scampered away after the trap door opened unexpectedly. “These aren’t all our traps, and some of them seem to be a bit old.”

Still, by testing four squirrels from different areas of the campground, Smith believes that he probably will find out if any have contracted the plague. “In 1989 we only tested three animals and one had it,” he said.

A mini-operating room is assembled on a picnic table. Smith carefully places a heavy plastic bag over the trap and opens the door, shooing the first squirrel into the repository.

McCann hands Smith an anesthetic--a container filled with ether-soaked cotton balls--that is dropped into the bag.

The squirrel passes out within a minute. Smith flattens out the plastic and drives the syringe directly into the tiny animal’s chest, pulling a full vial of blood. “We do a straight heart shot because if we do a clean first-stick and quickly take it out it doesn’t do any harm,” Smith said.

McCann then takes the squirrel from the bag, holds it over a white steel tray, and combs it for fleas with a toothbrush.

The fleas are gathered in a small glass sample container, Smith said. Blood samples are tested by University of California at Davis biologists, and should any come back positive, the fleas will then be tested, to learn if they are passing the disease.

When an area is defined as a plague zone, environmental health officials and U. S. Forest Service employees usually do what is called a flea knockdown, in which they dust rodent burrows with insecticides, Smith said.

“Basically, you get the flea count down, and as you do, the possibility of transmission goes down too,” Smith said.

If a large population of rodents is thought to have been infected, eradication programs are possible, Smith said.

Smith warns backcountry visitors to avoid all contact with rodents regardless of the season. He suggests that hikers avoid animal burrows and use insect repellent.

“Somebody has to come in very close contact with an animal, or a flea, to contract bubonic plague,” Myers said. “You have to sort of just be at the wrong place at the wrong time.”