by [email protected]
Animal welfare means protecting animals from people,
animal control means protecting the people from the animals. If we can
assuage public concern about diseases that can be transmitted to people
by domestic and wild animals, we may be able to foster tolerance for all
As incredible as it seems in this day and age, we all
know of someone who still believes that cats shouldn't be around babies
because they “suck the breath out of the baby”; or that pregnant women
must surrender their housecats to shelters to avoid toxoplasmosis. Not
all stray dogs are rabid, not all rodents carry disease, and not all cat
scratches lead to cat-scratch fever.
By far, it is not contact with wild animals but with our
own pets that produce the most incidences of zoonotic disease
transmission. The most common route of zoonoses is bite wounds.
Statistics show that 4.7 million people are bitten by dogs every year in
the United States. Of these, approximately 800,000 people require
medical intervention. That is, each year 1.8% of the U.S. population is
bitten by a dog, and 0.3% of the U.S. population seeks medical care for
a bite (Centers for Disease Control).
Bite wounds can lead to serious bacterial infections
because of the oral bacteria in a pets’ mouth. Cat Scratch Fever is
caused by a bacteria called Bartonella Henselea found in cat saliva and
on cat claws. Intestinal worms of pets are also transmissible to people.
Roundworms and hookworms are passed in the feces of infected animals. If
ingested by humans, the worms can migrate through the body (visceral
larval migrans). They generally migrate to the eye, leading to
blindness. Toxoplasmosis is a single-celled protozoan. It is of
particular consideration to immunosuppressed people and pregnant women.
The prevailing source of toxoplasmosis in people is from eating
undercooked meat, but it is considered a zoonotic disease because a cat
can contract toxoplasmosis from eating infected raw meat, and pass it on
in their feces. It can then be transmitted to people who clean their
litter boxes, or children who play in areas where infected cats have
defecated. The simple way to avoid toxoplasmosis is to wear rubber
gloves when cleaning a litter box, or have another family member do it.
Another prevalent source of zoonotic infections is pet’s
skin. Ringworm (which is a fungus, not a worm) can be passed from pets
to people and from people to pets. Zoonotic diseases and the risk of
bite wounds can be reduced by early puppy/kitten socialization,
commonsense hygiene and annual visits to a vet for parasite checks and
Medical professionals working in human hospitals
frequently get prophylactic vaccinations such as hepatitis, influenza,
and tetanus and are routinely tested for tuberculosis. However,
animal-care workers, with the possible exception of pre-exposure rabies
vaccines, do not normally get vaccinated against zoonotic diseases. Yet,
surprisingly, the incidence of zoonoses is relatively small.
Veterinarians, and others whose jobs bring them in close working contact
with animals, have no higher degree of the illnesses of diseases that
also occur in animals than the general population does.
When an alarming number of persons are diagnosed with
the same disease within a short period of time, an epidemic is declared.
Epizootic is the word we use when the same thing happens to animals.
Because the threat to human life is so viable, there are several laws in
place, which are meant to protect the general public from diseases that
can be passed from animals to humans. Some of these laws cross state
lines. Most state laws require diligent reporting of instances of
animal-related diseases in humans. Some of the diseases or conditions
are declared so dangerous as to be a threat to the public health.
Treating physicians and veterinarians, as well as the caregivers of
people and animals who have been found, upon their death, to have had
this disease, are required by law to report the event within 48 hours of
the finding. The list of zoonotic diseases includes 52 major diseases,
but not all of them are subject to government regulations regarding
reporting of confirmed diagnoses of these diseases. Some of the diseases
of which some states require due notification are:
Animal bite by potentially rabid animal
Food or waterborne diseases Botulism
Meningococcal Disease Pertussus
* (only if found in human subject)
In order to keep zoonotic diseases in check, vaccines
have been developed to protect not only domesticated house pets and
their owners, but zoo animals and cattle as well. These vaccines not
only protect the animals, but the animal-care workers who are in close
proximity to large numbers of animals. Most of the vaccines that are
offered and used extensively are done so on a voluntary basis. The
rabies vaccine, however, is a mandatory vaccine in the United States.
Rabies is a highly contagious, deadly zoonotic disease.
It’s a common misconception that only dogs and raccoons can get rabies.
The truth is any mammal can get rabies. The most common carriers of
rabies are skunks, bats, coyotes and foxes. However, there are
documented cases of rabid horses and cows as well.
If any disease has fed into the hysteria surrounding
diseases that can affect both human and non-human animals alike, it’s
rabies. Known medically as hydrophobia, rabies is a serious virus
infection of the central nervous system, transmitted by the bite of
infected animals. So a certain amount of education is necessary to avoid
any unfortunate end results of this hysteria: the unnecessary and
unwarranted killing of animals who intrude on human territory simply
because they “may have rabies”. A collective, deeper understanding of
rabies and how it is identified and transmitted may go a long way toward
saving the lives of animals who are not infected with the rabies virus
but are at risk for being killed anyway. The two most common of these
classes of animals are domestic pets that bite; and wild animals that
appear in and around populated communities.
Rabies occurs rarely in the United States, but there is
still public fear and substantial prevention efforts continue. The
reason for this very serious effort at prevention is that rabies is
always a deadly disease for both humans and non-human animals. There is
no cure for rabies. The vast majority of rabies cases reported to the
Centers for Disease Control and Prevention (CDC) each year occur in wild
animals like raccoons, skunks, bats, and foxes. Domestic animals account
for less than 10% of the reported rabies cases, with cats, cattle, and
dogs most often reported rabid.
There are two forms of rabies: Furious rabies largely
affects the brain and causes an infected animal to be aggressive or
excitable (the very picture of the foaming-at-the-mouth, "mad dog" image
people have of rabies). Paralytic or "dumb" rabies, mainly affects the
spinal cord, causing the animal to be weak-limbed, lethargic, and unable
to raise its head or make sounds because neck and throat muscles are
paralyzed. In the beginning phase of paralytic rabies, an animal may
also appear to be choking (USDA).
In the case of transmission by wild animals, it is
important to note that very few of the wild animals that wander into a
person’s backyard is rabid. Wildlife experts agree that people should
not encourage wild animals into their yard by feeding them or leaving
garbage cans in such a way as to entice wild animals such as raccoons
and foxes. Most wildlife rehabilitators believe that wild animals should
be left alone. If they are creating a nuisance, the most humane way to
rid a property of unwanted feral animals is to wait until they leave
their nest (usually at night), and then render the space uninhabitable
by placing a blockage of some sort over the access point. Of course, you
can’t do this if the home is serving as a nest for infant animals.
The bottom line is that there are a lot of diseases,
some still being discovered, that are easily transmissible from animals
to humans. There are many more that are not so easily transmitted.
Education on the part of the public will go a long way toward keeping
safe from zoonotic diseases and saving wildlife that are sometimes
killed for no reason other than “they carry disease”. Complying with
local regulations for domestic animal vaccinations, and becoming more
educated and tolerant of wild animals is the key to keeping rabies and
other zoonotic diseases in check, and living in harmony with other
Go on to Great
European Circus Not So Great For Animals
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