For the first time in a quarter-century, Allegheny County officials have discovered a rabid squirrel.

The squirrel met its end Monday after being caught by a dog in Highland Park.

Guillermo Cole, spokesman for the Allegheny County Health Department, said a woman was walking her dog in the park and the dog caught the infected squirrel.

"The dog went over, held the squirrel in its mouth for some time, and dropped it," Cole said.

The dog's owner, a 50-year-old city resident,, tried to help the wounded animal by moving it near a tree.

But in its waning moments of life, the squirrel bit back.

"She was bitten on her finger after an encounter with the dog and squirrel," Cole said.

The squirrel didn't die immediately, and was transported to a county lab for testing. In bite cases, the county tests dead animals for rabies because of an ongoing outbreak in the local animal kingdom.

Rabies is regularly reported in raccoons, bats, foxes and skunks, but only seven squirrels with the virus have been found in Pennsylvania since 1951.

The rabies finding was confirmed by two tests -- an awed technician double-checked, noting that even a 27-year veteran of the Health Department couldn't recall another rabid squirrel.

The dog owner has started receiving a month-long series of shots to ward off illness. Her dog's rabies shots were up-to-date, but the pet is being confined to its yard for up to three months as a precaution.

"We think this underscores the fact that high-risk species aren't the only animals that can carry the rabies virus," Cole said. "People need to avoid contact with all wild animals, and all stray dogs and cats."

Richard McGarvey, spokesman for the state Department of Health, likened the squirrel case to last year's unusual finding of a rabid otter in Delaware County. A game warden killed the otter after it charged children playing in a stream.

A rabies infection can cause either aggressive or sluggish behavior in an infected animal. McGarvey noted one time when a Pennsylvania resident spotted a raccoon languishing on the roadside, picked up the animal and took it to a veterinarian for care.

Sure enough, the raccoon had rabies. In such a case, public health authorities are careful to track down the people involved because rabies infections are so dangerous.

"Rabies is fatal in humans -- once you start to show symptoms, there's no coming back," said McGarvey. The last human case in Pennsylvania involved a young Lycoming County boy who died in 1984.

From the 1950s through the 1970s, there were fewer than 100 reported cases of animal rabies per year in the state, McGarvey said. Now, it's not unusual to have more than 400 cases, annually.

State officials believe the virus made a comeback after rabid raccoons from Florida were introduced into West Virginia and Virginia. There have been 372 animal rabies cases in Pennsylvania as of Nov. 18.

Allegheny County has seen fewer rabies cases this year than last, but officials are still urging caution.

Pet owners should avoid contact with animals their pet has encountered, Cole said. They also should refrain from touching their pet with bare hands after such an encounter -- especially if saliva from another animal is on their pet. Rabies virus is transmitted through saliva.

If a pet has such an encounter, the owner should wear rubber gloves while washing their pet with soap and water and call their veterinarian.

Encounters with strange animals, especially encounters that involve bites, should be reported promptly to the Health Department at 412 687-2243.