Rabies is an ancient viral infection, dreaded worldwide and “dreaded” is an excellent description. In animals, Rabes is a fatal viral encephalitis transmitted by bite or scratch from claws that have been contaminated with the virus from licking. In humans it is 99.9% fatal. Worldwide, rarely a report will surface of a survivor. Underdeveloped impoverished countries have a much higher rate of infection due to poor prevention in concentrated populations.
Fortunately, other than administering vaccines, my experiences with Rabies are limited. In college I had a fraternity brother that was bitten by a stray dog that got away. He went through a series of post-exposure injections. Back then they were administered daily for 12 doses into the abdominal musculature. Ouch! By injection #8 he couldn’t stand up straight and by the last dose he couldn’t get out of bed. When I was a junior in veterinary school, many members of the senior class were exposed from an infected horse. He was admitted for inability to swallow. Thinking he had an apple lodged in his esophagus the horse had a stomach tube passed orally several times. Unfortunately, an advanced symptom of rabies infection is inability to swallow. Several students were faced with the painful decision to take the post-exposure injections. My senior year we had a cow admitted to the hospital drooling and apparently unable to swallow, and thankfully because of the case the year before proper precautions were taken and nobody was exposed.
So, anyone with pets or children, or anyone that just happens to be Homo sapiens should know the basics about Rabies.
- All mammals can be infected but 5 are considered reservoirs: foxes, raccoon, skunks, coyotes, and bats.
- The disease is contracted by a bite or possibly a scratch from an infected animal. The virus replicates and travels up the nerves to infect the brain. A large number of viral particles are found in the salivary glands.
- Infection has also been reported to infect via aerosol in bat caves.
- Exposure of infected saliva in open wounds from other animals such as horses and cows, as discussed above, may be a source of infection.
Symptoms can vary but generally follow 3 stages:
- Prodromal: Changes in attitude such as sudden shyness, apprehension, and anxiety.
- Furious: Irritability progresses to erratic behavior. This can include biting snapping and overt aggression.
- Paralytic: In-coordination, change in tone of bark, excessive salivation, inability to swallow, seizures, and paralysis.
- Animals known to be infected are euthanized.
- New treatments have been developed in humans increasing the chance for survival. However, infection still carries a grave prognosis.
- Vaccinate pets. The vaccines are effective when giving the first dose after 12 weeks of age, boostering at a year of age, and then every 3 years for the lifetime of your pet.
- Do not keep wild animals as pets.
- Educate your children and yourself. Do not handle wild animals in distress. If you find a raccoon, fox, skunk, or coyote that is obviously sick leave it alone and contact proper wildlife authorities.
Other prevention facts:
- If a person is bitten by an apparently healthy dog or cat, the animal is isolated for 10 days. If no symptoms develop the bite victim is safe. Infected dogs and cats do not shed the virus earlier than 3 days before symptoms develop.
- In most states if an un-vaccinated dog or cat is exposed to a rabid animal euthanasia may be recommended or the pet must be quarantined for at least 6 months.
- Hawaii and some countries are rabies free. They have extremely strict import laws. We know because we’ve been involved in the paperwork and vaccine protocol and serology to get someone’s pet to Hawaii. It is a long and arduous process.
- Bats have extremely small sharp teeth and bites may not bleed or even be noticed. So, if you have a bat loose in a room with a pet or sleeping infant call the proper authorities for capture and testing of the bat.
- In the event a pet that is suspected of having rabies is euthanaized the animal's head must be sent in for testing.
The incidence of positive rabies in wildlife has been on the increase in this country. Climate change appears to be creating longer warm seasons allowing wildlife to roam longer and migrate further. Endemic areas have crept up the Atlantic states and across Pennsylvania. Ohio has warded off further migration in wildlife via an oral vaccine administered in bait.
In domestic animals the greatest incidence of the rabies virus has been in cats. Obviously, feral cats are probably the reason. However, nationwide the number of cat visits to veterinary hospitals have been on the decline. The economy and the declined use of other vaccines in cats are probably the reason. Cats are not small dogs. They tend to hide problems until crisis state, so I cannot emphasize enough, make that annual visit with your cat and semiannual visit for older cats.
It’s not in the news much, but it is out there. I get reports annually about reported positive rabies in wildlife in Ohio and southwestern Ohio’s numbers are on the increase. Avoid a potential tragedy, vaccinate your pets.
Blog post written by Dr. Miller, to learn more about Rabies visit the Center for Disease Control's website.