Vaccinations and Pets: Are We Overvaccinating Our Pets?

[Guest guest]

" ...started looking into exactly how the recommendations for annual vaccines

arose, they started realizing that they were just that — recommendations.

And in fact, they were not based on scientific evidence. "

http://abcnews.go.com/sections/living/DailyNews/pet_vaccination010906.html

After all, vaccines are a standard in health care. We vaccinate our children

against hepatitis, polio and influenza when they're infants and toddlers,

giving up to two boosters of some vaccines until puberty. But then we stop.

Not with our pets, though. In fact, we continue bolstering the immunity of

our pets until they are well into their senior years. That has spawned a

debate as fierce as any fighting pit bull: To vaccinate or not to vaccinate.

Many veterinarians believe the practice of annual vaccinations is an

unnecessary evil, responsible for such diseases as allergy, seizures,

anemia, even cancer. They say vaccinations make our animals vulnerable to

some of the top diseases plaguing our pets, and that rather than building up

immunity we are overwhelming their immune systems. Others would rather stick

to tradition and say that vaccinating has warded off the most deadly animal

diseases over the past 30 years, so why question it now.

Lack of Scientific Evidence

Dr. W. Dodds, president of the nonprofit animal version of the Red

Cross called Hemopet, was one of the pioneers of the vaccine debate, an

issue she says has been percolating for the past 10 years. She says as the

profession started looking into exactly how the recommendations for annual

vaccines arose, they started realizing that they were just that —

recommendations. And in fact, they were not based on scientific evidence.

Dodds says that after 20 years of following the United States Department of

Agriculture and the drug manufacturer's recommendations to make annual

vaccines a standard in veterinary care, professionals who first challenged

the standard school of thought were considered rebels. Her arguments were

challenged by other veterinary professionals whose belief in the duty to

vaccinate was galvanized by episodes such as the deadly parvo virus epidemic

in the late 1970s that killed thousands of dogs and was only halted by mass

administration of the parvo vaccine.

But Dodds says an unfortunate observation led many vets to begin to

reconsider current vaccination protocol. In 1991, three years after

Pennsylvania issued a mandatory rabies vaccination requirement for cats, Dr.

Mattie Hendrick's lab at the University of Pennsylvania noted a connection

between the surprising increase in the number of sarcomas, or cancerous

tumors, and vaccination in cats. It seemed that in some cats, rabies

vaccinations were leading to an inflammatory reaction under the skin.

Shortly after, researchers at the University of California at showed

that feline leukemia vaccines were also likely to cause sarcomas, and to an

even greater degree than the rabies vaccine. Further investigating led

researchers to estimate the prevalence of vaccine-induced sarcomas to be as

much as one cat in 1,000, or up to 22,000 new cases of sarcoma a year.

Soon, veterinary professionals began to suspect vaccination as a risk factor

in other serious auto-immune diseases. Researchers surmised that, in some

animals, vaccines were stimulating the animal's immune system against his or

her own tissues, leading to potentially fatal diseases such as auto-immune

hemolytic anemia (AIHA) in dogs. Researchers began to suspect delayed

vaccine reaction for the cause of such chronic conditions as thyroid

disease, allergy, arthritis and seizures in cats and dogs.

Such observations led to a 1995 Journal of the American Veterinary Medical

Association article that concluded there is " little scientific documentation

that backs up label claims for annual administration of most vaccines, " and

that the only vaccine tested routinely for duration is the rabies vaccine.

In addition, the article suggested that though some vaccines should be given

annually, giving others only every few years would be sufficient because of

potential risks associated with them.

Hesitation to Vaccinate

Dodds says that in her own practice, she only vaccinates when necessary.

Rather than automatically giving boosters, Dodds gives annual titers, or

tests, to check the level of antibodies (disease fighting cells) in the

blood to determine if boostering is necessary. Though she expects that

immunity would be conferred for life, she says that titers offer " an added

measure of security. "

Though many vets have in fact begun to change their vaccination habits, many

continue to administer annual shots. Dodds believes that the resistance is

not so much a financial issue since vets should still asks clients to come

in for an annual check-up and titers. Rather, it's more about changing

attitudes.

" For decades we were told that this is what we had to do, " Dodds says. " The

USDA put the recommendation on the label. Our confidence was totally shaken

up. "

Non-Vaccination a Greater Danger?

Still, many vets believe it's too early to change procedure. The say that

until more is known about the immunity conferred by some vaccines, it's best

to take a conservative approach. They emphasize the fact that annual

vaccinations have been effective at decimating the incidence of formerly

common, potentially lethal viral diseases such as feline panleukopenia,

rhinotracheitis, feline leukemia, canine distemper, hepatitis and canine

parvo virus. And with the incidence of the deadly feline leukemia virus so

high, it is too hard and too risky to determine which cats are at risk.

Dr. Klingborg, former Chairman of the Council of Biologic and

Therapeutic Agents of the American Veterinary Medical Association (AVMA) and

Assistant Professor at the University of California at , says that

while the vaccination issue is a complicated one, nonvaccination is a major

error.

" In most cases, the threat to the animals' health from nonvaccination is

much greater than vaccination, " he says. " The diseases are real, severe and

common. "

Klingborg says the vaccination debate could be settled by more information

on the duration of immunity most vaccines impart.

Conclusive Answers Difficult

But while vaccine companies are under no legal obligation to demonstrate

duration of immunity, that question may remain unanswered for some time.

Dr. Wynn, a Georgia-based veterinarian and former board member of the

American Holistic Veterinary Medical Association says that the problem with

obtaining immunity duration information is monetary and political.

" This information would have to be gained by challenge studies in which you

give viruses to animals inoculated over five to 10 years ago, " she says.

" You would have to keep those animals in a controlled environment for this

time — only drug companies have that kind of money. "

Wynn says that for the drug companies, the decision is based on priorities —

it's either more products or immunity studies, not both.

_________________________________________________________________

Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp