Monday, August 6, 2012

Rabies in Washington State

By Dr. Beth Guerra

I grew up in the Midwest, where rabies was more prevalent in wildlife such as bats, raccoons, coyotes, and skunks as well as the rare household pet. In Washington state the primary animal that has been identified is the bat. Although the risk is fairly low (less than 1% of bats are infected), the virus is nearly always fatal and care should be taken to avoid exposure.

In 2011, 11 bats in Washington state tested positive for rabies in the following counties: Chelan, Clallam, Island, King, Lewis, Pierce, Snohomish, Walla Walla, and Whatcom. As of July 2012, there have already been three infected bats in similar counties. The most recent case of rabies in a household pet (cat) was in 2002 in Walla Walla county, and the last two human cases were in 1995 and 1997. All of these cases were infected with bat rabies.

Bats that carry rabies are usually clinically ill and cannot fly properly. This makes them more likely to be found by humans or household animals. There have also been reports of bats getting into houses and being found in closets or shoes. The teeth of the bat are very small and a bite may not be easily detected, especially if a person is bitten while sleeping.

Rabies is a virus that affects the central nervous system. The virus is found in saliva and transmitted via bite or scratch wounds. Household pets are exposed through wildlife and are usually the source of exposure for humans. Early symptoms may include headache and fever, but within two to eight weeks can progress to confusion, paralysis, and difficulty swallowing. If exposure is suspected, the exposed person usually begins a regimen of injections, including rabies immunoglobulin as well as the vaccine, over a two week period.  The best treatment is prevention.

As of January 1, 2012, current rabies vaccines are required for all dogs, cats, and ferrets. Rabies vaccines are readily available at veterinary clinics and are inexpensive. If a household pet is exposed to rabies, there is mandatory six month quarantine, so vaccination is best.

The following information was taken from the Washington State Department of Health:

What should I do if an animal bites me?
Clean the site of any animal bite with soap and water. Contact your health care provider and Public Health Communicable Disease and Epidemiology at (206) 296-4774 to determine the potential for rabies exposure, the need for treatment, and to decide whether or not to test the animal for rabies.
What should I do if I find a bat in my living space?
Do not touch the bat. Close the doors and windows to the room. Wait until the bat lands on the floor or a wall. Wearing leather or other thick gloves, capture the bat in a can or box without touching it. Seal the container and call Public Health Communicable Disease and Epidemiology at (206) 296-4774. The health department will help you determine if any people or pets in your home may have been exposed and can arrange to test the bat for rabies, if needed. “Bat proof” your home by making sure open windows have screens and that other small entry points—such as cracks, crevices, or holes—are sealed.
What treatment is available after exposure to rabies occurs?
Safe and effective treatment following potential rabies exposure should begin as soon as possible after the exposure occurs. Treatment is a series of shots. These shots, called post-exposure prophylaxis (PEP), include one dose of human rabies immunoglobulin (HRIG) and four doses of rabies vaccine given on a specific schedule over a 14-day period. People with weak immune systems will also need a fifth dose of vaccine and a blood test to check that the vaccine worked.
Treatment can be arranged through your health care provider and your local health department.
What can I do reduce the risk of rabies exposure for my family and me?
  • Do not handle wild animals, especially bats.
  • Teach your children never to touch or handle bats, even dead ones. Have your children tell an adult if they find a bat at home, at school, or with a pet.
  • If you see a wild animal leave it alone.
  • Do not keep wild animals as pets.
  • Keep bats out of your living space by “bat proofing” your home.
  • Pets may get rabies if bitten by a rabid animal. Protect them and yourself by getting them vaccinated routinely. Dogs, cats, and ferrets are now required to be vaccinated in Washington. Consult your veterinarian for vaccine recommendations.

Sources: Washington State Department of Health