Bat rabies is rare, but county health officials say pet owners should be careful

Rabies may be rare in Washington County, but watch out for sick bats this summer.

A recent encounter a Gaston woman had with a rabid bat demonstrates the disease is alive and well in some wild creatures.

Rabies can exist in many mammals, but its most common form in Oregon occurs in bats, the winged creatures often associated with dark caves and Tim Burton movies. Even so, most bats don't have the disease - and recent run-ins with rabid bats by Washington County residents are considered more a warning of a rare public health concern than a sign that rabies is on the rise.

"We have no evidence of an elevated problem," said Dr. Gary Oxman, Washington County health officer.

Earlier this month, a Gaston woman was bitten by a bat as she tried to remove it from her dog's mouth, according to county health officials. The bat tested positive for rabies, making it the first case of bat rabies in the county this year.

The woman was given an antibody to immediately protect her, and has started a four-part vaccine session to help her body build up an immunity to the virus.

This sort of preventive treatment is almost always effective when it's administered on time, but otherwise rabies can be fatal, Oxman said.

The dog, although vaccinated, will be quarantined in the owner's home for 45 days as a precaution, Oxman said. If the dog does have rabies, symptoms will most likely show by the end of the quarantine.

But back in 2010, a 15-month-old puppy was less fortunate when it encountered a sick bat.

Calvin Nakao was walking Molly, his golden retriever puppy, through the orchards by his home in Cornelius when the dog started pawing at something on the ground.

Nakao saw that it was a bat, and pulled Molly away. Noticing that the bat was sick, he called his vet, who told him to take it to the Audobon Society.

He put it in a box, and transported it to Portland for testing.

After the bat tested positive for rabies, Nakao was told by the Oregon state veterinarian Brad LeaMaster that since Molly was too young to be vaccinated in time, she had to be quarantined in complete isolation for six months or be euthanized.

It wasn't an easy decision.

"I didn't think it was fair for a little puppy to be isolated for that long," he said. "We all decided it was better to put it down. It was a pretty sad choice."

Rabies rare in Oregon

Colin Gillin, state wildlife veterinarian, said there are seven strains of rabies, and the virus can be found in different mammals like skunks, raccoons and foxes, in addition to bats.

However, few bats actually have the virus. Gillin said only 1 percent of the total population of bats carries rabies, and one in 10 sick bats found by humans are rabid.

"As bat populations go, when you see bats flying around the percentage that are healthy or thriving is high," he said.

Though many people think of rabies and connect it to Old Yeller - the lovable yellow dog from Fred Gipson's 1958 children's novel who got the virus from a wolf - Gillin said rabies is not that easy to spot. He said people who find a sick bat won't be able to tell if its rabid.

Calling rabies a "smart virus," Gillin explained that it enters the blood stream through a bite or open wound and then travels up the nervous system to the brain, where it replicates. The virus then travels down a cranial nerve and straight to the pharynx, making it impossible for the animal to swallow. Rabies also attacks the salivary glands, which is why an infected mammal drools excessively.

"It's like it's got a mind of its own," he said of the virus. "It's got this all figured out and it's a microscopic virus."

Oxman said human exposure to rabies is especially rare, and when humans do get rabies, it can take weeks or even years for the symptoms to show.

Because the virus travels through the nervous system, the farther away the infected area is from the head, the better, Oxman said. If the infected person is treated before symptoms show, they will be just fine. But if rabies reaches the brain, it can cause severe neurological damage and is almost always fatal.

Oxman said the best way to avoid rabies is to leave sick bats alone. If you have to be in contact with a bat, he said, always wear leather gloves or use tongs, and put it in a cooler with ice to transport it. If bitten by a bat, Oxman said to wash the wound with soap and water.

Vaccination a key

Health officials say pet owners should always make sure their dogs and cats have up-to-date rabies vaccinations.

Soon after putting Molly down, Nakao got another golden retriever named Hana.

He said he often takes Hana, which means flower in Hawaiian, out to the orchard. Nakao thinks the case of rabies Molly stumbled upon was rare, and is not concerned that Hana will do the same.

And though Nakao hasn't noticed any bats on his property recently, Hana was vaccinated at 12 weeks of age.

"We made sure of that," he said.

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