this healthcare necessity to fit your dog’s needs
By Caroline Coile,.PhD
“Dog Watch: The Newsletter for Dog People”,
Holly Hill Lane
what dog owners have been told to do for years: Vaccinate
thoroughly and vaccinate
often. But that practice has now come under scrutiny,
leaving many tesponsible
dog owners vacillating about vaccinating.
Vaccination should not be a regimented, one-size-fits-all
to Cynda Crawford, DVM, PhD. Dr. Crawford, of the University
of Florida School of Veterinary Medicine, is one of a
growing number of veterinarians
and researchers who are striving to define guidelines in an effort
to help dog owners and veterinarians "give the right
vaccine at the right
time to the right individuaL" That means that every
vaccination should be
evaluated in terms of a dog's age, lifestyle, potential for
exposure, and consequences
should the dog become infected.
vaccines—called core vaccines—protect against such
devastating or widespread
threats that it's necessary for every dog to receive them.
include those for distemper, infectious hepatitis,
virus and rabies. Other vaccines - called non-core vaccines
against less dangerous or more localized diseases, and are
not for every
it's not just a question of what vaccinations to give, but
how often to give
them. For the past 20 years, the American Veterinary Medical
recommended revaccinating dogs annually as the safest way to
ensure all dogs
had sufficient immunity. But that practice has also come
into question because
many vaccines protect dogs for longer than a year. Vaccine
manufacturers must demonstrate their vaccines are effective
for the duration
claimed on their labels. To do this, they expose dogs to the
organism at various times following vaccination. Because
are expensive, most manufacturers stop them after
demonstrating the vaccine
protects for a year. The vaccine is then labeled for
giving rise to the recommendation for annual revaccination.
However, recent studies performed by independent groups have
shown that modified
live vaccines for distemper, parvovirus, canine infectious
parainfluenza protect for at least five to seven years.
Based on such studies,
many veterinary schools are now recommending revaccinating
intervals as opposed to yearly.
Crawford feels that we are probably vaccinating dogs with
too many vaccines
too often. But what is the harm? Some vaccinations may cause
adverse reactions or even a mild form of the disease they're
against. Modified "live" vaccines such as those
for distemper, parvovirus,
canine infectious hepatitis, parainfluenza and kennel cough
- can cause
disease in some animals.
vaccines - such as those for coronavirus, leptospirosis,
Lyme disease, giardia and rabies - are mixed with an
adjuvant, usually aluminum
hydroxide, that boosts the immune response to the vaccine
but also increases
the chance of adverse reactions.
reactions may include localized swelling, pain or hair loss;
with hives, itching, and vomiting or diarrhea. About 10,000 adverse
reactions to vaccines in animals are voluntarily reported in
States each year.
where adverse reactions must be
reported, the percentage of adverse reactions is less than
0.1 percent of vaccine
more widespread concern is the fear that vaccinating too
often may lead to certain
chronic diseases in some susceptible individuals, or to
disorders, particularly immune mediated hemolytic anemia.
Several reports have linked vaccination to the development
of immune-mediated joint,
neurological and thyroid diseases, but as yet no controlled
study has shown
a cause-and-effect relationship.
pet owners, uneasy about the possibility of either over- or under-vaccinating,
turn to antibody titer checks to evaluate a dog's level of immunity
to a particular disease. Unfortunately, titer levels do not necessarily
correspond with immunity levels. High titer levels don't guarantee
immunity, and low titer levels don't guarantee
susceptibility. No standardize
tests or interpretations are available, so samples sent to different
laboratories may produce different recommendations. Because
based on humoral immunity, they cannot evaluate other
such as immune memory cells or cell-mediated or mucosal
pet owners turn to nosodes or natural substances in place of
vaccinations. (Homeopathic nosodes are orally administered products
made from highly diluted infected material.) Many
do this with inadequate information, and end up with
unprotected dogs. In the only controlled study of their
efficacy, nosodes against parvovirus were
shown to be totally ineffective in preventing disease.
the horizon are more genetically engineered recombinant
vaccines that produce
immunity through cell-mediated immune mechanisms. Such
vaccines are considered
less likely to produce adverse effects, but also may be less
to produce titer indicators of immunity.
American Animal Hospital Association (AAHA) plans to issue
updated canine vaccination
guidelines in the spring of 2003. Although the report is not
there is speculation that it will also advocate a national
to document adverse reactions to vaccines, improvements in
and three-year rabies boosters. Dr. Crawford points out,
"The overall goal of vaccination is protection of the
population as a whole, which can be achieved by vaccinating
more dogs, but vaccinating
each dog less."