Rabies, Vaccination and Public Health

When I was a kid, I remember watching a movie on a Saturday afternoon. It was about a man, bitten by an angry dog, who became obsessed by the notion that he had contracted rabies. I'm pretty sure this movie was black and white, from the 1950s or even 40s. The entire film followed the hapless fellow as he lurched from one room in his apartment to another, thirsty but unable to drink a glass of water (a nod to rabies' misnomer, "hydrophobia"). As it turned out, he didn't have rabies at all, just a hysterical rendition of the illness.

Rabies is a deadly disease, no doubt about it. Of course, there are other diseases just as horrible, but rabies occupies a special place in our psyche. The attack, possibly a maiming one, of a virus-maddened animal (remember, "Cujo"?); the creeping insidiousness of the disease as it takes hold, causing lack of control, madness, then an agonizing death. No wonder we fear it!

Cats, more than dogs, tend to exhibit the furious (aggressive behavioral symptoms) v. the dumb (progressive paralysis) type of rabies. Changes in behavior, particularly an aggressive fearlessness, lack of coordination and hypersensitivity to stimuli are symptoms of furious rabies. Once the virus replicates at the infection site, it moves through the body via the nervous system to the brain, then the salivary glands. This progression is the same in dumb rabies, where paralysis starts in the throat causing an inability to swallow (aha!). The infected animal can shed the virus for months or even years, as in cases where the animal recovers without exhibiting debilitating symptoms. So, even if an animal doesn't die of rabies, he can still infect others, who may not fare so well.

Rabies is one of the few true zoonoses (pathogens transmissible from animals to humans) and this fact, along with the disease's seriousness, make it a true public health threat. Since the virus may take several weeks to move from the point of entry to its destination in the brain, people handling these animals run a very real risk of infection. Hence the laws requiring pet (particularly dog) vaccination against rabies.

Next week we'll take a look at the efficacy, side effects and risks associated with the rabies vaccines being used on our cats and dogs.
Chat later!