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To Vaccinate Or Not To Vaccinate That Is The Question
These are the notes from a vaccination seminar given in Victoria,
BC in 1998.
The question if our pets need their vaccines every year keeps coming
up. The following information was extracted from a seminar attended
by Dr. Smith, given by Ron Schultz in North Caroline September
2004 and his news release published March 2003. Ron is a veterinary
immunologist and researcher at the University of Wisconsin-Madison
School of Veterinary Medicine. He has been studying the effectiveness
of canine and feline vaccines for the last 30 years. His studies
showed that immunity after vaccination in dogs could last as long
as a lifetime. The question if we are over vaccinating our animals
was raised when many veterinarians noticed that there was an increase
in diseases such as skin problems, allergies and autoimmune diseases
after vaccinations. In cats, tumors at the site of the vaccination
injection have been well documented.
Just like in people, an animal’s immune system gets fired
up when a pathogen such as a virus enters the body. These disease-fighting
cells are called B and T lymphocytes. They not only destroy the
virus; they remember what it looks like, so they can fend it off
in the future. This is the basis on how vaccines (which are killed
or live weakened pathogens) can protect against future diseases.
Vaccines protect people for life; Ron Schultz’s research
has shown the same for dogs and cats.
Schultz recommends that animals be vaccinated with the "core
vaccines" only. These are distemper for dogs and cats, parvo
for dogs, leukemia for cats and rabies for both. He recommends
not vaccinating for Lyme's disease due to reported adverse reactions
such as immune mediated poly arthritis. Kennel cough vaccine does
not give adequate protection and the disease is not a life-threatening
disease.
Ron Schultz recommends vaccinating dogs no more often then every
three years for the core vaccines. He also found that adult cats,
which had received a vaccine for leukemia once in their life, could
not contract the disease in adult life. The Tree of Life Veterinary
Care has been following the antibody levels in the blood of vaccinated
animals and found these antibodies lasting three to seven or more
years. One 11-year-old dog had high antibodies against the rabies
vaccine 10 years after the last vaccination! Ron Schultz vaccination
schedule has now been embraced and recommended by the American
Animal Hospital Association.
For more information visit the website of the Wisconsin University
at:
www.news.wisc.edu/release/8413.html or contact Ron Schultz at: manningj@svm.vetmed.wisc.edu
Vaccinations
Every year new vaccinations come out and our animals (and kids!)
seem to get numerous vaccinations in the early part of their lives.
Are we doing the right thing and could all these multiple vaccinations
possibly cause any harm? We will try to clarify the various infectious
diseases that dogs and cats can get, which ones of these could
be fatal and which ones cause relatively mild signs. We will also
discuss the latest recommendations as to the timing and frequency
of vaccinations, based on research done at universities.
Infectious Diseases in Dogs:
Canine Distemper
This is an acute or sub-acute febrile disease of dogs and related
carnivores including ferrets and bears. It is spread worldwide
and has a high fatality especially in young unvaccinated animals.
The virus is a paramyxo virus related to measles and rinderpest.
The virus suppresses the immune system, often resulting in other
infections such as pneumonia or parvo.
Clinical signs include such symptoms as high fever 3-6 days after
exposure, which lasts for 2 days. The second fever phase occurs
several days to weeks later with discharge from the eyes and nose,
diarrhea and vomiting. There is loss of appetite, general depression
and dehydration. Sometimes an allergic skin rash is noticed. Nervous
signs can occur concurrently or afterwards and can vary from seizures,
incoordination, pacing, circling, a tic or tremor. In cases of
encephalitis the footpads can be affected and become hard and cracked.
Prognosis: This is always guarded since dogs with mild signs may
seem to recover and then develop neurological signs, which might
be irreversible or fatal. Many young puppies with compromised immune
systems die of the disease in spite of extensive (expensive) treatment.
The disease still occurs in unvaccinated canine populations. Immunity
after vaccinations in dogs over 4-6 months last 3-7 years, maybe
life long.
Canine Hepatitis:
This highly infectious disease is caused by two adeno viruses.
The virus is easily destroyed by disinfectants, but can survive
in cold climates for a long time and for years in a frozen state.
Signs can vary from mild transient general depression followed
by ocular lesions as uveitis (eye inflammation) and keratitis,
resulting in a blue eye. The virus can also affect the upper respiratory
tract. The disease can be fatal and eye changes can be irreversible.
This disease has not been diagnosed in the western world for many
years and questions arise if it has been eradicated. The need for
vaccination against disease is questionable.
Parvo Virus Infection:
This is an acute and highly contagious viral infection in dogs
and related animals. The disease is most severe in animals under
1 year of age. Clinical signs are severe bloody diarrhea 2-6 days
after exposure. Vomiting, depression and anorexia are common symptoms.
The virus suppresses the immune systems and other diseases can
occur simultaneously. There is a high rate of fatality and those
that recover can develop cardiac problems as cardiomyopathy or
encephalitis. Duration of immunity as result of vaccinations in
dogs, vaccinated at 4-6 months of age is 3-7 years, maybe a lifetime.
Corona Virus:
This virus also causes diarrhea and enteritis. It is seen predominantly
in shelters, boarding kennels and show dogs. The diarrhea can be
severe, but is seldom fatal and positive antibodies are found in
75 % of dogs with transient diarrhea. The effectiveness of vaccination
against this disease with a killed virus is not established. The
importance of this disease in puppies is questionable; it rarely
causes a problem in the adult dog. The need to be vaccinated for
the disease is questionable.
Kennel Cough (Infectious Tracheobronchitis):
Bordetella bronchiteptica is one of the many viruses that can cause
upper respiratory disease in dogs. Other viruses are canine para
influenza and herpes infection. Both viruses can survive for months
in the environment. The virus is present in secretion of nose and
trachea and spread through aerosol or direct contact.
Typical symptoms are a harsh barking cough and a fever up to 105
F. Most dogs recover spontaneously and some require antibiotics
for secondary infections. Show dogs and dogs boarding in kennels
are most at risk. Intra-nasal vaccination is more effective than
subcutaneous or intra muscular. I see an increase of nasal tumors,
chronic infections and fungal infections in dogs. The question
arises here if intra nasal vaccinations could possibly contribute
to this. Also the shedding of the modified life virus of the vaccine
has possibly been the cause of outbreaks of upper respiratory infections
in kennels after recently vaccinated dogs were introduced.
In the early stages Kennel cough can be effectively treated with
the Chinese herbs Gan Mao Ling and Yin Chiao. Duration of immunity
after intra nasal vaccination is likely 3 months or less. Protection
is questionable.
Lyme's Disease:
This disease is caused by a spirochete borelia burgondorferi. The
disease is transmitted via the tick Ixodes. The disease is diagnosed
with greater frequency in humans, dogs and horses. The signs are
varied and include fever, lethargy, poor appetite, lymphadenopathy,
lameness and arthritis. Endocarditis and myocardial necrosis might
also occur. Meningitis and renal changes can also be a result of
this disease. The disease can be effectively treated with tetracycline,
ampicillin and erythromycin. Effectiveness of vaccination is questionable.
Recent research in the USA has shown that there was an increase
of immune mediated arthritis in individuals vaccinated with Lyme’s
vaccine. Vaccinations should only be considered in high-risk areas
such as the South Eastern United States.
Leptospirosis:
This disease is also caused by a spirochete. Wild and domestic
animals serve as a reservoir. The virus is mostly shed via the
urine and infection often occurs via pools of warm and stagnant
water. The liver and kidney are mostly affected. A very acute infection
can result in death without many symptoms. Less severe infections
show fever, lethargy, anorexia, vomiting, dehydration and reluctance
to move. Progressive destruction of the kidneys is evident in the
progressive thirst and urination. This disease is transmittable
to humans. Vaccinations are recommended in endemic areas with vaccines
against the type of leptospirosis present in the area. Most
current canine vaccines no longer contain the leptospirosis fraction,
since L canicola and icteroheamoragica are not commonly present
anymore. Check to see if your area is infected with leptospiroses
and which type.
The vaccine against this disease has the most reported adverse
reactions. The Leptospirosis fraction used in the current vaccine
is not the same as what is present in nature and does not
give a cross protection. If your area has Leptospirosis, please
make sure that the fraction used in the vaccine actually protects
your animal.
Rabies:
This viral disease causes encephalitis in warm-blooded animal including
humans and is almost always fatal. Wild animals such as skunks
and bats are the reservoirs for re-occurring infections. Infection
occurs through saliva via a bite or ingestion of infected tissue
or even inhalation. Signs may occur 3-8 weeks after exposure. Signs
are a change in behaviour from irritability and biting to being
extremely timid and paralysis. In the “ furious rabies” the
animal will become hypersensitive and may bite any object that
moves or with any loud noise or bright light. They may show seizure
type activity. In the paralytic rabies the animal may become very
timid and wild animals may appear tame. Their tongue may hang out
and they may not be able to swallow, resulting in hydrophobia.
Since this is a fatal untreatable disease, vaccinations against
this disease are recommended. The duration of post vaccination
immunity has not been researched very well, it likely lasts for
7-10 years after the initial vaccination at 6 months or older.
There are now non-adjuvated rabies vaccines available for cats,
which can also be used for animals at risk. Law requires re-vaccinations
every three years, especially for border crossing with the USA.
Infectious Diseases In Cats
Feline Distemper (Panleukopenia):
This disease is caused by a parvovirus. It can survive for many
months or years in the environment. It is shed via the feces and
or vomiting. It can survive in cages, bowls, and litter boxes.
Inter uterine infection can cause cerebellar hypoplasia. The disease
is fatal in young unvaccinated kittens. Kittens from vaccinated
queens are protected with maternal antibodies up to12 weeks of
age.
Signs of the disease are vomiting, fever, lethargy, anorexia, diarrhea,
dehydration. Vaccinations are essential in kittens over 10 weeks
of age. Revaccinations are done up to 16 weeks of age with 4-6
week intervals. (Over 21 days and less than 60 days). Duration
of immunity post vaccination is currently accepted as being 3-7
years.
Feline Herpes Virus/ Feline Calici Virus:
The majority of the feline upper respiratory diseases (80-90%)
are caused by herpes infection and calici virus. The virus is shed
in ocular, nasal and tracheal secretions. Calici virus may also
be shed via the feces. Infection can be transmitted from cat to
cat or via hands, bowls or shoes. The disease is mostly self-limiting,
but many animals remain chronic carriers with periodic outbreaks.
Some of the chronic gingivitis has been attributed to this disease.
Herpes infection can cause ulcers where the ocular or nasal discharge
comes in contact with the skin, similar to cold sores in people.
Calici virus can cause ulcers on the tongue. The currently used
vaccine is a modified life virus vaccine, which is known to shed
the virus, resulting in outbreaks of upper respiratory disease
in shelters and catteries. This often results in chronic ocular
and or nasal discharge especially if the animal is exposed to stress
during or post vaccination. Duration of immunity post vaccination
is unknown and ranges from a few months to 7 years.
Chlamydia:
This upper respiratory infection is caused by the bacteria Chlamydia
psittaci. Transmission is mostly from cat to cat. Signs are ocular
and nasal discharge and sneezing. The disease is relatively low
in occurrence accounting for approximately 5% of upper respiratory
infections.
Feline Leukemia:
This disease is caused by a retro virus. In higher populated areas
the occurrence is greater than in rural areas. The virus can be
carried by clinically healthy unaffected cats or by chronically
ill cats. Transmission occurs through long intimate contact or
bite wounds, in-uteri or via the mother’s milk. Kittens under
16 weeks of age are more susceptible to infection than animals
over 16 weeks of age. Currently it is questioned if adult healthy
cats can get infected with this disease.
The virus suppresses the immune system and signs occur from this
suppression. These signs can be from chronically ill cats
with recurring infections including abscesses or gingivitis. The
virus can also cause neoplasia (Cancer). Vaccinations are recommended
for susceptible groups only. Duration of immunity post vaccination
is 3-7 years. Indoor cats cannot contract the virus and do not
need to get vaccinated against this disease.
Feline Infectious Peritonitis (F.I.P.):
This disease is caused by a Corona virus. Transmission occurs via
oronasal contact or contaminated feces. Infection can also happen
via the queen’s milk. Clinically healthy carriers create
a reservoir. Most cats carry antibodies against a corona virus;
these antibodies may give “ false positives” in cats
tested for FIP. There is a wet and dry form of FIP. The “dry” form
creates inflammatory granulomas in the abdomen, chest and brain,
while the “wet” form causes an ascitis or pleural effusion.
Only cats at risk should be vaccinated. The vaccine is not without
risk. Duration of immunity is likely life long.
Feline Immune Deficiency Virus:
This Retro virus causes symptoms similar to Human Immune Deficiency
Virus (AIDS). Transmission is via bite wounds and breeding. No
vaccine is available yet for this disease.
To Vaccinate Or Not To Vaccinate?
Vaccination protocols have been developed with the best knowledge
available to prevent potentially fatal diseases in our pets, horses,
livestock and humans. More and more vaccines are now available
and there is a concern that we are overdoing it.
In general, the kittens and puppies receive antibodies from their
mothers in the uterus and via the colostrum and early days of lactation.
This is of course if the mother has an adequate immune status and
is healthy. These maternal antibodies last for 8-16 weeks. These
maternal antibodies inactivate vaccines and vaccinating animals
at 4 or 6 weeks of age might be surplus or even contra indicated.
According to Ron Schultz, Veterinary Immunologist at Wisconsin
University, there are core vaccines and non-core vaccines. The
core vaccines are for fatal and generally common diseases while
the non-core vaccines are for susceptible groups only (i.e. groups
most likely to get the disease). In the cat, the CORE vaccines
are feline panleukopenia (FPV), feline viral rhinotracheitis (Feline
Herpes), feline calici virus (FCV) and rabies.
The non-core vaccines are leukemia (FeLv), feline infectious peritonitis
(FIP), and ringworm. These diseases only occur in cats going outdoors,
being boarded, going to shows or living in a multiple cat household.
In dogs, the CORE vaccines include distemper, parvo and rabies.
The non-core vaccines are leptospiroses, corona, bordetella, hepatitis,
para influenza and Lyme’s disease.
When vaccinating a cat or dog the risks of vaccination should be
weighed carefully against the benefits. For the core vaccines
the benefit clearly outweighs the risk. The non-core vaccines should
only be given to animals that are at risk to get the disease. Indoor
cats will not get exposed to leukemia; new additions to the family
should be tested prior to allowing them into the household. Cats
in a breeding situation or in a multiple cat household are
at greater risk and leukemia and FIP should be considered. So indoor
cats do not need to be vaccinated against leukemia.
Dogs in the city or living in areas where there are no ticks do
not need to be vaccinated against Lyme’s disease. The occurrence
of positive ticks is very low even in the so-called endemic areas.
Only 1 or 2 ticks have been identified being positive for Lyme’s!
The possible introduction of modified virus leading to vaccine
induced poly arthritis is bigger then the odd chance that the dog
might contact Lyme’s disease. Multiple vaccinations with
killed vaccine could possibly result into reactions against the
vaccine or adjuvance. Intranasal vaccinations for upper respiratory
diseases are better than parental injections. But this vaccine
is a non-CORE vaccine.
An animal should not be vaccinated:
* When it undergoes anesthesia or surgery, dental cleaning, etc.
* During pregnancy -This will not only cause a failure in vaccinations,
but also could lead to cerebellar hypoplasia and meningitis. If
your queen or bitch is not adequately vaccinated prior to conception
it is better not to breed her.
* Any animal with an immune impairment such as immune deficiency,
Feline leukemia, allergies, autoimmune diseases etc, should not
automatically be vaccinated. Please discuss the danger of re-stimulating
the immune system to maintain these diseases versus protection
for the animal.
* Any animal prior, during or shortly after transportation or going
into a new home.
* Any animal having had an adverse reaction to previous vaccinations.
(Split up your vaccines!)
* Any animal that is not 100% healthy!
What else can we do?
The need for annual revaccination lacks adequate scientific data
to validate this practise. How then can we determine that the animal
needs a booster vaccination? In human medicine, duration of antibodies
is based on a blood titre that shows adequate protecting antibodies
against the disease in question.
There are several types of titers we can use: the virus neutralizing
antibody titre, the immune fluorescent antibody, and the hemagglutination
antibody titre. They don’t all correlate and are not all
the same. The word is not out yet on which one is the most reliable.
There is also a local cell mediated immunity for which we cannot
test. If we would use the same parameter we use for humans as “ safe
and not needing a vaccine” for the animals, we would find
that most vaccines give three to seven (feline distemper) years
immunity. The truth of the matter is that we lack understanding
of all the factors that play a role in immunity and response to
diseases. Titre testing many animals will give us a better understanding
of how long humoral antibodies last.
Cell (immediate) immunity can possibly be stimulated with homeopathic
nosodes. These can be given orally to animals with an adequate
blood titter for the disease in question. It is not known how often
this needs to be repeated. This (the nosodes) is certainly a good
way to activate the immune response in case of an outbreak.
These nosodes are NOT an alternative to vaccinations!! At the very
most they might stimulate cellular immunity in already vaccinated
(or exposed) animals.
A nosode can also be given, after the first initial vaccinations
have been given as a yearly (or 3 year) booster.
A nosode can also be used when an animal comes down with the disease
it has been vaccinated against in the last week (typical for URI)
or to a puppy in the early stages of Parvo infections, or to kittens
entering a shelter (where they often pick up URI or distemper).
To prevent diseases in any animal, the most important thing is
to maintain an optimum health through good balanced nutrition and
exercise. In Kirk’s Current Veterinary Therapy Vol 11 page
205, Drs. Schultz and Phillips question the following: “A
practice that was started many years ago and that lacks scientific
validity or verification is annual revaccination. Almost without
exception there is no immunological requirement for annual revaccination.
The practice of annual vaccinations in our opinion should be considered
of questionable efficacy”.
I am sure that the last word has not been said yet on vaccinations!
References:
Central Laboratory News July 1999
The Globe and Mail: “Are vets barking up the wrong tree?” March
15 1999
CVMA “ Vaccinations and your pet 1999
“What’s new in thyroid diseases”, Dr. Jean Dodds DVM proceedings
American Holistic Veterinary Medical Association, Burlington 1997
Kirk Current Veterinary Therapy Vol 11
Homeopathy and vaccinations Dr. Christine Chambreaux DVM
Colorado State University - Dr. Shultz vaccination recommendations
American Association of Feline practitioners: Vaccination recommendations
Veterinary immunology. Ian Tizard.
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