SHOULD WE DO ABOUT RABIES?
April 3, 2011
the following questions about rabies.
Q. We watched
a raccoon climb a tree in our backyard one afternoon. We approached and
it just sat there, seemingly unafraid, on a limb five feet above the ground.
It started drooling and growling, so we backed away. Later that week we
found a dead raccoon in the backyard. Could the animal have had rabies?
A. It very
likely did have rabies, and leaving it alone was certainly the right thing
to do. Several aspects of its behavior are telling. First, it was out
in the middle of the day: Raccoons are usually nocturnal. Second, it let
you get close. Third, it was drooling, not something we want to see in
a raccoon, one of the most prevalent reservoirs for rabies. It probably
died because it was infected with the rabies virus.
to information received later from the same county, animal control picked
up two more strange-acting raccoons that were found to have rabies. Incidental
cases of rabies among wild mammals are not that unusual in many parts
of the country and are certainly no cause for alarm. Knowing about the
disease can help people avoid problems for themselves and for domestic
dogs and cats, all of which are susceptible to infection by the rabies
Q. What animals
A. Any warm-blooded
animal can harbor the virus. According to the Centers for Disease Control
the most common US wildlife species to be infected are foxes, skunks,
raccoons and bats. Unvaccinated domestic pets are also susceptible, as
are coyotes, which have become more prevalent in the Southeast in the
past two decades. The CDC notes that small mammals, including "squirrels,
rats, mice, hamsters, guinea pigs, gerbils, chipmunks, rabbits, and hares
are almost never found to be infected with rabies." They are not
known to have caused rabies in humans in the United States. One odd statistic
is that the woodchuck (aka, groundhog), has a high incidence of the disease.
According to some scientists, possums supposedly do not get rabies, although
they will certainly bite if given an opportunity.
virus is usually introduced by saliva during biting; rarely, it can enter
the body through mucous membranes. The virus multiplies in the nervous
system, and symptoms usually develop within three months, but occasionally
can appear in only a few days. Rabies victims have difficulty swallowing
water, because of paralysis of the throat muscles. The seeming aversion
to water led to the name "hydrophobia," which means fear of
water. The loss of muscular control of the throat muscles can also result
in excessive drooling, leading to the "foaming at the mouth"
line of safety precautions for dealing with rabies is pretty much common
sense. Don't pick up a drooling, growling raccoon (in fact, don't pick
up any wild raccoon). Likewise for sick or injured bats. Bats are beautiful
animals in flight, especially when they are eating mosquitoes, but if
you find one on the ground or in a house, don't let it bite you. CDC records
indicate that rabies has been documented in bats from all 48 of the conterminous
states. All domestic dogs and cats should be vaccinated, especially those
likely to go outside or come in contact with wild animals.
Q. I have heard some people suggest that we should start vaccinating wild
animals to prevent rabies epidemics. Is this feasible?
A. Such a plan would be costly--and it's unnecessary. Wild animals are
not the problem if we avoid situations in which we are likely to get bitten.
CDC records show that "control of dog rabies through programs of
animal vaccination . . . reduces the incidence of human rabies."
Rabid dogs are the cause of more than 90% of human infections of the rabies
virus and the source of more than 99% of human deaths from rabies worldwide.
We should have our pets vaccinated at a vet's or a rabies clinic, but
let's leave the wild animals to take care of themselves.
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