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It does look as if the tide is turning regarding yearly vaccs and immunity, etc.
The American Veterinary Medical Association Committee report this year states that 'the one year revaccination recommendation frequently found on many vaccination labels is based on historical precedent, not scientific data'.
In JAVMA in 1995, Smith notes that 'there is evidence that some vaccines provide immunity beyond one year. In fact, according to research there is no proof that many of the yearly vaccinations are necessary and that protection in many instances may be life long'; also, 'Vaccination is a potent medical procedure with both benefits and risks for the patient'; further that, 'Revaccination of patients with sufficient immunity does not add measurably to their disease resistance, and may increase their risk of adverse post-vaccination events.'
Finally, he states that: 'Adverse events may be associated with the antigen, adjuvant, carrier, preservative or combination thereof. Possible adverse events include failure to immunise, anaphylaxis,immunosuppression, autoimmune disorders, transient infections and/or long-term infected carrier states.'
The report of the American Animal Hospital Association Canine Vaccine Taskforce in JAAHA (39 March/April 2003) is also interesting reading: 'Current knowledgte supports the statement that no vaccine is always safe, no vaccine is always protective and no vaccine is always indicated'; 'Misunderstanding, misinformation and the conservative nature of our profession have largely slowed adoption of protocols advocating decreased frequency of vaccination'; 'Immunological memory provides durations of immunity for core infectious diseases that far exceed the traditional recommendations for annual vaccination. This is supported by a growing body of veterinary information as well as well-developed epidemiological vigilance in human medicine that indicates immunity induced by vaccination is extremely long lasting and, in most cases, lifelong.'
Further, the evidence shows that the duration of immunity for rabies vaccine, canine distemper vaccine, canine parvovirus vaccine, feline panleukopaenia vaccine, feline rhinotracheitis and feline calicivurus have all been demonstrated to be a minimum of seven years, by serology for rabies and challenge studies for all others.
The veterinary surgeons below fully accept that no single achievement has had greater impact on the lives and well-being of our patients, our clients and our ability to prevent infectious diseases than the developments in annual vaccines. We, however, fully support the recommendations and guidelines of the American Animal Hospitals Association Taskforce, to reduce vaccine protocols for dogs and cats such that booster vaccinations are only given every three years, and only for core vaccines unless otherwise scientifically justified.
We further suggest that the evidence currently available will soon lead to the following facts being accepted:
* The immune systems of dogs and cats mature fully at six months and any modified live virus (MLV) vaccine given after that age produces immunity that is good for the life of that pet.
* If another MLV vaccine is given a year later, the antibodies from the first vaccine neutralise the antigens from the subsequent so there is little or no effect; the pet is not 'boosted', nor are more memory cells induced.
* Not only are annual boosters for canine parvovirus and distemper unnecessary, they subject the pet to potential risks of allergic reactions and immune-mediated haemolytic anaemia.
* There is no scientific documentation to back up label claims for annual administration of MLV vaccines.
* Puppies and kittens receive antibodies through their mothers' milk. This natural protection can last eight to 14 weeks.
* Puppies and kittens should NOT be vaccinated at less than eight weeks. Maternal immunity will neutralise the vaccine and little protection will be produced.
* Vaccination at six weeks will, however, DELAY the timing of the first effective vaccine.
* Vaccines given two weeks apart SUPPRESS rather than stimulate the immune system.
This would give possible new guidelines as follows:
1. A series of vaccinations is given starting at eight weeks of age (or preferably later) and given three to four weeks apart, up to 16 weeks of age.
2. One further booster is given sometime after six months of age and will then provide life-long immunity.
In light of data now available showing the needless use and potential harm of annual vaccination, we call on our profession to cease the policy of annual vaccination.
Can we wonder that clients are losing faith in vaccination and researching the issue themselves? We think they are right to do so. Politics, tradition or the economic well-being of veterinary surgeons and pharmaceutical companies should not be a factor in making medical decisions.
It is accepted that the annual examination of a pet is advisable. We undervalue ourselves, however, if we hang this essential service on the back of vaccination and will ultimately suffer the consequences. Do we need to wait until we see actions against vets, such as those launched in the state of Texas by Dr Robert Rogers? He asserts that the present practice of marketing vaccinations for companion animals constitutes fraud by misrepresentation, fraud by silence and theft by deception.
The oath we take as newly-qualified veterinary surgeons is 'to help, or at least do no harm'. We wish to maintain our position within society, and be deserving of the trust placed in us as a profession. It is therefore our contention that those who continue to give annual vaccinations in the light of new evidence may well be acting contrary to the wefare of the animals committed to their care.
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Richard Allport, BVetMed, MRCVS
Sue Armstrong, MA BVetMed, MRCVS
Mark Carpenter, BVetMed, MRCVS
Sarah Fox-Chapman, MS, DVM, MRCVS
Nichola Cornish, BVetMed, MRCVS
Tim Couzens, BVetMed, MRCVS
Chris Day, MA, VetMB, MRCVS
Claire Davies, BVSc, MRCVS
Mark Elliott, BVSc, MRCVS
Peter Gregory, BVSc, MRCVS
Lise Hansen, DVM, MRCVS
John Hoare, BVSc, MRCVS
Graham Hines, BVSc, MRCVS
Megan Kearney, BVSc, MRCVS
Michelle L'oste Brown, BVetMed, MRCVS
Suzi McIntyre, BVSc, MRCVS
Siobhan Menzies, BVM&S, MRCVS
Nazrene Moosa, BVSc, MRCVS
Mike Nolan, BVSc, MRCVS
Ilse Pedler, MA, VetMB, BSc, MRCVS
John Saxton, BVetMed, MRCVS
Cheryl Sears, MVB, MRCVS
Jane Seymour, BVSc, MRCVS
Christine Shields, BVSc, MRCVS
Suzannah Stacey, BVSc, MRCVS
Phillip Stimpson, MA, VetMB, MRCVS
Nick Thompson, BSc, BVM&S, MRCVS
Lyn Thompson, BVSc, MRCVS
Wendy Vere, VetMB, MA, MRCVS
Anuska Viljoen, BVSc, MRCVS, and
Wendy Vink, BVSc, MRCVS
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Additional Sources of Information On the New Vaccination Schedule Below:
NEW PRINCIPLES OF IMMUNOLOGY Dogs and cats immune systems mature fully at 6 months. If a modified live virus vaccine is given after 6 months of age, it produces immunity, which is good for the life of the pet (ie: canine distemper, parvo, feline distemper). If another MLV vaccine is given a year later, the antibodies from the first vaccine neutralize the antigens of the second vaccine and there is little or no effect. The titer is not "boosted" nor are more memory cells induced. Not only are annual boosters for parvo and distemper unnecessary, they subject the pet to potential risks of allergic reactions and immune-mediated haemolytic anemia. There is no scientific documentation to back up label claims for annual administration of MLV vaccines. Puppies receive antibodies through their mothers milk. This natural protection can last 8-14 weeks. Puppies & kittens should NOT be vaccinated at LESS than 8 weeks. Maternal immunity will neutralize the vaccine and little protection (0-38%) will be produced. Vaccination at 6 weeks will, however, DELAY the timing of the first highly effective vaccine. Vaccinations given 2 weeks apart SUPPRESS rather than stimulate the immune system. A series of vaccinations is given starting at 8 weeks and given 3-4 weeks apart up to 16 weeks of age. Another vaccination given sometime after 6 months of age (usually at 1 year 4 mo) will provide lifetime immunity.
ANNUAL DOG VACCINES MAY NOT BE NECESSARY, SAYS UW VETERINARY IMMUNOLOGIS MADISON -
Once a year, Ronald Schultz checks the antibody levels in his dogs' blood. Why? He says for proof that most annual vaccines are unnecessary.
Schultz, professor and chair of pathobiological sciences at the University of Wisconsin-Madison School of Veterinary Medicine, has been studying the effectiveness of canine vaccines since the 1970s; he's learned that immunity can last as long as a dog's lifetime, which suggests that our "best friends" are being over-vaccinated.
Based on his findings, a community of canine vaccine experts has developed new veterinary recommendations that could eliminate a dog's need for annual shots. The guidelines appear in the March/April issue of Trends, the journal of the American Animal Hospital Association (AAHA).
Every year, when we take our dogs to the veterinarian's office, they could receive up to 16 different vaccines, many of which are combined into a single shot. Four of these products protect against life-threatening diseases, including rabies, canine parvovirus type 2 (CPV-2), canine distemper virus (CDV) and canine adenovirus type 2 (CAV-2); the rest protect against milder diseases to which only some dogs are exposed, including Lyme disease. But, as many veterinarians are realizing, over-vaccination can actually jeopardize a dog's health and even life. Side effects can cause skin problems, allergic reactions and autoimmune disease. Though the case in cats, not dogs, tumors have been reported at the site of vaccine injections. "These adverse reactions have caused many veterinarians to rethink the issue of vaccination," says Schultz. "The idea that unnecessary vaccines can cause serious side effects is in direct conflict with sound medical practices."
For 30 years, Schultz has been examining the need to vaccinate animals so often and for so many diseases. "In the 1970s, I started thinking about our immune response to pathogens and how similar it is in other animals," says Schultz. "That's when I started to question veterinary vaccination practices." Just like ours, a canine's immune system fires up when a pathogen,like a virus, enters the body. The pathogen releases a protein called an antigen, which calls into action the immune system's special disease-fighting cells. Called B and T lymphocytes, these cells not only destroy the virus, but they remember what it looked like so they can fend it off in the future. It's this immunological memory that enables vaccines, which purposely contain live, weakened or dead pathogens, to protect against future disease. But, as Schultz points out, vaccines can keep people immune for a lifetime: we're usually inoculated for measles, mumps and rubella as children but never as adults. So, can dogs be vaccinated as pups and then never again?
While evidence from Schultz's studies on both his own dogs and many other dogs from controlled studies suggests the answer is yes, Schultz recommends a more conservative plan based on duration of immunity and individual risk. Schultz says that core vaccines, or the ones that protect against life-threatening disease, are essential for all dogs, yet he does not recommend dogs receive these shots yearly. "With the exception of rabies, the vaccines for CDV, CPV-2 and CAV trigger an immunological memory of at least seven years," he explains. (Studies testing the duration of immunity for rabies shots show it lasts about three years.) For these reasons, Schultz suggests that dogs receive rabies shots every three years (as is required by law in most states) and the other core vaccines no more frequently than every three years. Some non-core vaccines, on the other hand, have a much shorter duration of immunity, lasting around one year. But, as Schultz points out, not every dog should get these types of vaccines, because not every dog is at risk for exposure.
Today, many vaccinated dogs receive a shot for Lyme disease. However, Schultz says that the ticks carrying the Lyme disease pathogen can be found in only a few regions of the United States. More importantly, Schultz adds, "The vaccine can cause adverse effects such as mild arthritis, allergy or other immune diseases. Like all vaccines, it should only be used when the animal is at significant risk." He notes that the Veterinary Medical Teaching Hospital at the UW-Madison School of Veterinary Medicine rarely administers the Lyme disease vaccine.
Another common vaccine that Schultz says is unnecessary protects against "kennel cough," an often mild and transient disease contracted during boarding or dog shows. "Most pet dogs that do not live in breeding kennels, are not boarded, do not go to dog shows and have only occasional contact with dogs outside their immediate family," Schultz recommends, "rarely need to be vaccinated or re-vaccinated for kennel cough." Schultz says that it's important for veterinarians to recognize an individual dog's risk for developing a particular disease when considering the benefits of a vaccine. "Vaccines have many exceptional benefits, but, like any drug, they also have the potential to cause significant harm." Giving a vaccine that's not needed, he explains, creates an unnecessary risk to the animal.
Recommending that dogs receive fewer vaccines, Schultz admits, may spark controversy, especially when veterinarians rely on annual vaccines to bring in clients, along with income. But, as he mentions, annual visits are important for many reasons other than shots. "Checking for heartworm, tumors, dermatological problems and tooth decay should be done on a yearly basis," he says. "Plus, some dogs, depending on their risk, may need certain vaccines annually." Rather than vaccinating on each visit, veterinarians can use a recently developed test which checks dogs' immunity against certain diseases. Schultz adds that veterinarians who have switched to the three-year, instead of annual, vaccination program have found no increase in the number of dogs with vaccine-preventable diseases. "Everyday, more and more people in the profession are embracing the change," notes Schultz. And, that the new vaccination guidelines supported by the AAHA, along with the task force members representing the American Colleges of Veterinary Internal Medicine, Veterinary Microbiology and the American Association of Veterinary Immunologists, is evidence of just that.
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