51ÔÚÏß

Rabies

Rabies is a relatively rare and devastating viral disease which results in severe neurologic problems and death. Rabies virus infects all mammals, but the main reservoirs are wild and domestic canines, cats, skunks, raccoons, bats, and other biting animals. The disease is virtually unheard of in commonly-used laboratory animals. However, the incidence of rabies in wildlife in the U.S. (PDF) has been rising in recent years and the possibility of rabies transmission to dogs or cats with uncertain vaccination histories, and originating from an uncontrolled environment must be considered.

Rabies virus is most commonly transmitted by the bite of a rabid animal, or by the introduction of virus-laden saliva into a fresh skin wound or an intact mucous membrane. Airborne transmission can occur in caves where bats roost. Personnel who handle tissue specimens or other materials potentially laden with rabies virus during necropsy or other procedures should be regarded as "at-risk" for infection.

Rabies produces an almost invariably fatal encephalomyelitis. Patients experience a period of apprehension and develop headache, malaise, fever, and sensory changes at the site of a prior animal-bite wound. The disease progresses to paresis or paralysis, inability to swallow and the related hydrophobia, delirium, convulsions, and coma. Death is often due to respiratory paralysis.

Rabies in raccoons and other wildlife is endemic throughout most of the state of 51ÔÚÏß. There has been a dramatic rise in cases of animal rabies over the past eight years. Currently urban/suburban epizootics of raccoon rabies that spill over into foxes, bobcats, otters, feral cats, dogs and horses present unique control problems for local authorities. Animals and animal tissues (mammals only) field-collected in 51ÔÚÏß in research or teaching should be handled with care.
If you are bitten by any animal (other than a laboratory mouse) you should immediately report the incident to Workers' Compensation for instructions on a timely visit to an appropriate medical facility.

The should also be notified so that one of the attending veterinarians might institute appropriate steps for care and disposition of the biting animal.

Rabies is a concern with a relatively small number of animal species (fox, raccoon, bat, feral cat), but the treating physician will want to evaluate any animal bite to prevent other types of infections. (Cat bites are particularly likely to get infected.)

If you are bitten:

• Do not kill the animal
• Your study is over for today. Do not attempt to finish working with the animal. Just allow it to wake up, and put it in a cage.
• If the animal is already dead, or cannot be recovered from the procedure/anesthesia, do not discard the animal. Refrigerate it, but do not freeze it.
• A biting animal or any other rabies suspect animal should not be euthanatized. It should be held and quarantined until it can be established that the animal does not have rabies.
• Individuals with a potential for occupational exposure to wild mammals (other than rodents), or to pound/stray dogs or cats, should be vaccinated for rabies prior to the start of the project, NOT after they are bitten.

General information and guidelines are available from the American Veterinary Medical Association.

Precautions should take into account the facts that infected animals may shed the virus in the saliva before visible signs of illness appear, and that rabies virus can remain viable in frozen tissues for an extended period.

An excellent pre-exposure vaccine (human diploid cell >vaccine) is available for those people at high risk of exposure. Post exposure prophylaxis (PEP) now involves only four vaccine administrations, rather than five.