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compiled by the Australian Association of Holistic Veterinarians, May 2004. This paper is intended to initiate discussion in order to compile a policy enabling the AVA to give broad recommendations to Australian veterinarians on the vaccination of cats and dogs, in light of current research data which infers that some current routine vaccination practices may not be in the best interests of all animals. Recommended additional reading: Clinical use of serum parvovirus and distemper virus antibody titers for determining revaccination strategies in healthy dogs, L. Twark, WJ Dodds. Report of the American Animal Hospital Medical Association Task Force: 2003 Canine Vaccine Guidelines, Recommendations and Supporting Literature. I also suggest downloading this article by Prof R Schultz, "Considerations When Designing a Safe and Effective Vaccination Program for Dogs" at: www.ivis.org There are also several copies of a file containing more references and much more extensive data for further reading into the areas discussed in this paper. Copies can be obtained by phoning 0403180567. The first question to ask is: Why do we give dogs and cats annual booster vaccinations, and why do we vaccinate them for the diseases we do, and at the ages that we do, at the moment? It is important for all small animal veterinarians (and ideally other stake holders in the industry too), to explore the answers to this question thoroughly. The next question to ask, which I will attempt to answer, but needs a lot more discussion than this document, is: Why not continue current vaccination practices for dogs and cats? Sufficient research papers now show that significant adverse effects to canine and feline vaccination occur to warrant using only minimum essential vaccination. (This statement is expanded and fully referenced in section A below). It therefore may not be medically appropriate to vaccinate animals any more frequently than is necessary for protection against disease. Vaccinations are not double blind placebo trialed by the manufacturers, they are usually only researched using viral challenge on limited numbers of animals in a laboratory, not in a field (real life) situation, and manufacturer's research has usually only been carried out for up to one year. The manufacturers of vaccines base their recommendations for use of their vaccines on their own such research data. Many other, independent and more longitudinal field trials, carried out by reputable and experienced scientists, have shown that less frequently than annual vaccination maintains immunity to most dog and cat diseases which are vaccinated against in Australia. These trials also suggest that vaccinating for only essential ("core") diseases, avoiding vaccinating when maternal antibody is present in puppies/kittens, and avoiding vaccinating unhealthy animals should be standard practice. (This statement is expanded and fully referenced in B below). Apart from the animal welfare considerations, veterinarians can find themselves open to litigation if an animal reacts adversely to a vaccination that cannot be proven to be necessary for the animal. Legal processes rely on "standard" or "normal" veterinary practice for reference, so the AVA needs to be clear about the definition of this in order to appropriately advise its members. It is also very important in maintaining the respect the public has for the veterinary profession for the future, that we represent the animals' best interests by diligently applying up to date scientific knowledge as it comes to hand. Another important problem for our profession to address is that significant numbers of animal owners are seeking the advice of non-vet natural therapists, who often suggest no or inadequate vaccination, which may not in the best interests of their pet's health. A. How Significant are the Adverse Affects to Dog and Cat Vaccination? Most veterinarians are familiar with the hypersensitivity or anaphylaxis symptoms possible after vaccination. Beyond these immediate reactions, other acute events (eg fever, pain, behaviour change, innappetance etc) tend to occur 24 to 72 hours later. Delayed type immunological responses, primarily autoimmune disease, can occur 7 to 45 days later (1,3,4,5). Different types of delayed adverse effects are also documented, and include mortality from high-titered measles vaccine in infants, canine distemper antibodies in joint disease in dogs (see file), and feline injection - site fibrosarcomas (12-18). Clinical signs and diseases resulting from the above 3 categories of non - anaphylactic reactions include fever, stiffness, sore joints, abdominal tenderness, susceptibility to infections, demodectic mange and allergy, neurological disorders and encephalitis, autoimmune haemolytic anaemia (AIHI), immune-mediated thrombocytopaenia (IMT) (1,2,3,4, 5,6,8,11). Hepatic enzymes may be markedly elevated and liver or kidney failure may occur by itself or accompanied by bone marrow suppression (3). Seizures can occur, sometimes in conjunction with autoimmune thyroiditis, AIHA and IMT (1,3). Postvaccinal polyneuropathy is a recognized syndrome (3,4). Abortion and death have occurred in pregnant vaccinated dogs and kidney failure in sled dogs (3). At least 2 papers indicate that dogs and cats are significantly more likely to present to vets in the weeks or months following their annual vaccination (55% of all presentations in a year were in the first 3 months following vaccination in one paper), than they are for the latter part of the year, inferring that their annual vaccination has rendered the animal more likely to suffer from a variety of diseases and symptoms (31,32, file). Therefore there are probably many such cases of vaccine adverse reaction that go unnoticed, and are difficult to definitely correlate to vaccination. It is known that most dogs undergo an immune suppressive picture leukogram a few days post vaccination (CSL data). In the human medical field, where more research has been funded, there are numerous adverse effects definitely correlated to vaccination, even though the adverse effects occur several weeks or months after the vaccination, eg childhood diabetes (abstract in file), autism, cot death, asthma, leukemia (33). Vaccination has been suspected, by several authoritative workers in this field, to cause widespread and unrecognised immune system malfunction in humans (34). It has been postulated by several of the referenced authors that the increasingly large number of animals suffering allergy, autoimmunity, cancer and other chronic disease may be in part related to overuse of vaccines. More veterinary data is needed in this area of adverse reaction to vaccination. It is important for all vets and practitioners to be more aware of, and report, all these possible adverse vaccine events to the Australian Pesticides & Veterinary Medicines Authority (tel (02) 62723651 for adverse effects forms). B. Which, and How Often, do Dog and Cat Vaccinations Need to be Given? To answer this question, it needs to be recognized that present vaccination protocol may sometimes not conform to sound immunological principles in 3 ways. a. The presence of maternal antibodies should preclude vaccination. The practice of vaccinating puppies before maternal antibody has worn off (9 weeks old or more) means that not only is the vaccination of not much use in producing antibodies, but the puppy's or kitten's immune system is subjected to an immunological challenge which may not be possible for it to manage successfully, resulting in a weakened immune system or even disease. The function of maternal antibodies are to protect the puppy/kitten when it is too immature to cope with such challenge, either by disease or by vaccination. Therefore vaccinating a puppy or kitten prior to 8-9 weeks old, unless it is an orphan, or the mother does not have antibodies, is not a sound medical act. Many cat breeders have found that cat flu signs can be more prevalent if kittens are vaccinated prior to weaning, but that giving the first vaccination at about 10 weeks of age, just when the maternal antibodies are waning and also when the body is just old enough to cope with such an immune challenge, is more likely to lessen cat flu in kittens. Vaccinating puppies and kittens before being fully weaned is likely to be less effective and more likely to increase the chance of adverse effect or immune suppression. This could be why some puppies suffer diseases they have been vaccinated for too early, eg parvovirus, cat flu, and possibly why carrier states of cat flu in pedigree (ie less immunocompetent) cats may occur. b. Only healthy individuals should be vaccinated. Vaccinating animals when not optimally healthy is a contraindication written on many vaccine pack instructions. Dogs and cats should not be vaccinated if suffering from any of the following conditions. Bacterial, viral or parasitic infection, chronic allergy, arthritis, spondylosis, chronic colitis, recurrent pancreatitis, KCS, AIHA, IMT, liver/kidney/heart/repiratory disease, on immune suppressive drugs, cancer, or if pregnant, if under anaesthetic, or if recently had an accident, surgery or emotionally traumatic event. In summary, the animal needs to be healthy at vaccination time. It has been shown conclusively that vaccinating humans when slightly malnourished can greatly increase the likelihood of adverse reaction, as detailed in Dr A. Kalokerinos' book 'Every Second Child', an account of an up to 50% death rate in Aboriginal babies a few days after routine vaccination in the 1970's, decreasing over the years as nutrition and management standards were improved. It is likely, therefore, that a healthy diet in animals is likely to be important in decreasing adverse affects to vaccination and reducing infectious disease incidence, a factor which should be considered in any vaccination program. A recent survey of Australian GP's found that 54% were vaccinating children when there was a clear contraindication due to existing illness (33 p21, ref cited). There could be a similar problem with veterinarians vaccinating sick animals, possibly increasing the likelihood of adverse reaction, and we all need to be aware of this possibility. It is an important potential litigation issue, quite apart from the animal welfare aspects. c. Monovalent (single) vaccination is preferable to polyvalent (multiple) vaccination. Polyvalent vaccination containing vaccine for non - life threatening or non - endemic diseases may render immunity to the endemic, life-threatening diseases less potent. The body is equipped to only respond to one infectious disease at a time in nature. For example, in an area where parvovirus is the only dangerous local disease, vaccinating puppies for kennel cough and hepatitis and distemper may render the parvoviral fraction of the vaccine less effective, thus increasing the danger of parvoviral infection of the pup. A monovalent vaccination of parvovirus only may well protect the pup more fully to parvovirus. Attached to this document is the Report of the American Animal Hospital Association Canine Vaccine Task Force 2003 Canine Vaccination Guidelines and Recommendations, which extends this principle by defining "core vaccines" which protect against endemic, life-threatening disease, which for most areas in Australia are distemper and parvovirus for dogs. These are the 2 diseases which may be endemic and dogs need to be protected against. Distemper is not endemic in some areas. Vaccinating a dog for hepatitis (and distemper) when there is no threat of disease may increase the likelihood of adverse reaction to vaccination, maybe render other more necessary vaccines less effective and therefore is unlikely to be of overall benefit to the dog. Non - life threatening or "non - core" diseases are listed also in the 2003 report of the American Animal Hospital Association Canine Vaccine Task Force. Kennel cough is the best example of a non-core disease for dogs in Australia. Veterinarians may choose to use kennel cough vaccines if the threat of kennel cough is deemed to be likely to seriously threaten an individual dog's health, and is worth the immunological load placed on the dog by increasing the polyvalancy of a vaccination program. We may see a decline in kennel cough in dogs with the introduction of less frequent vaccination, because average immune status of dogs will be higher. The attached reports show that parenteral (injectable) bordatella bronchiseptica vaccine does not have a track record sufficient to continue its use. Intranasal PI and BB prior to boarding or annually, or triennial Parainfluenza (given with core vaccine/s), would all be better options than the current annual use of PI and BB. Canine coronavirus vaccination has been shown conclusively to not be worth using at all (Schultz & AAHA report). Programs for leptospirosis and other "non-core" vaccinations need to be assessed on a local/individual basis according to the animal's best health benefits. Canine Vaccination. Canine vaccination program options to consider for our discussions for Australian dogs could include the suggestions by the American Animal Hospital Association task force (attached) and this document needs to be read, together with the second attachment, "Considerations In Designing Effective and Safe Vaccination Programs for Dogs" by R. D. Schultz. These 2 papers explain the methods of assessing immunity via challenge with virus and measuring blood antibody levels, both methods appearing to correlate sufficiently for us to rely on blood antibody testing as being a reliable means of assessing immunity in dogs. See attached the AAHA Report, the article "Clinical Use of Serum Parvovirus and Distemper Virus Antibody Titres for Determining Revaccination Strategies in Healthy Dogs" by L. Twark and W. J. Dodds., and in the file, the article by RD Schultz "Considerations in Designing Effective and Safe Vaccination Programs for Dogs", which can be accessed on line at www.ivis.org. Document no. A0110.0500). The above papers conclude (based on several other listed references) that well over 90% of dogs have a high enough antibody titer to withstand viral challenge for at least 5 years following MLV vaccinations for canine distemper, hepatitis, parvovirus and parainfluenza, measured since their 15 month old booster. Choosing a three year interval between booster vaccinations is an arbitrary, conservative and safe figure, and designed as a guide only. Even five years would be acceptable. Ideally, the individual dog's antibody titer is the best guide for that dog. Based on this research data, the following is a suggestion for a canine vaccination program for Australian dogs: Core Vaccinations Canine Distemper (if endemic) and Canine Parvovirus Vaccination (modified live, or killed vaccines) at about 9 weeks old, or just after weaning, eg when new pup has settled in new home for 2 or 3 days. (Orphans or when mother has insufficient or dubious antibody levels, give killed vaccines every 2 to 3 weeks from about 5 weeks of age, according to case). Modified live Canine Parvovirus (and Canine Distemper if endemic) at 12 to 14 weeks of age. Modified live Canine Parvovirus (and Canine Distemper if endemic) at 15 months of age, then every 3 years thereafter, if dog is healthy. The preferred option to triennial vaccination would be to take blood at dog's annual check up, for antibody assay of core diseases, and only vaccinate if antibody levels drop below levels able to prevent disease. One possibility would be to recall dogs annually, and use monovalent vaccines only (see above discussion on monovalent v. polyvalent vaccines) in rotation, eg parvo only at 2 years of age, distemper only at 3 years of age, parainfluenza only for dogs 4 years of age, then repeat cycle. Adding Canine Adenoviral Hepatitis vaccine at this later stage, maybe just once or twice in the dog's adult life, would likely render titers acceptable for the dog's life, while covering the population for recurrence of the disease, in preference to subjecting a young puppy to a vaccine for a non-core disease. Non-core vaccinations These would be given as deemed necessary for the individual dog, eg Intranasal Parainfluenza + Bordatella Bronchiseptica could be given prior to boarding dog in kennels if necessary (effective for < 6 months) or given at the annual vet check up. Parainfluenza could be included with core vaccine triennially or only as needed according to titers, if deemed a significant health threat. Many dogs may be better off not vaccinated for kennel cough at all. This program may be limited by vaccine companies not manufacturing vaccines separately. Veterinarians, as the main consumer of veterinary vaccines, need to request single (monovalent) vaccines from the vaccine manufacturers, to best benefit the needs of animals. Simple titer testing trials on dogs in Australia could prove or not this suggestion to be worthwhile adopting as policy. Footnote Antibody titre tests can be carried out by sending at least 2ml plain clotted blood sample to: Vetpath Laboratories 39 Epsom Ave Ascot WA 6104 www.vetpath.com.au Blood is sent to Scotland on Monday, results back on Friday. Cost parvo or distemper or parainfluenza antibody titre is $45 Cost for all 3 together is about $85 (at time of writing). The more clients opt for this, the better it gives us a sense of how effective our Australian vaccination programs are. Feline titers cost about $120 to the client, and are not popular. Feline Vaccination Following basically the same discussion as for dogs, we suggest for similar reasons the program for cats as recommended by Dr Darren Foster, exactly as suggested and referenced in the proceedings of the ASAVA section of the annual AVA conference in Adelaide, April 2002, page 2 (attached). This program was the recommendation from a task force of feline specialist veterinarians. Feline Enteritis (Panleucopaenia) vaccine for kittens at about 10 weeks of age, ie post weaning, then repeated at 12 to 14 weeks of age. Most cats were found to be immune for life after these 2 vaccinations. Given that some may not be, booster vaccinations may be advisable at 15 months of age, then at the most every 3 years thereafter. Feline Herpes/Calici virus combined vaccine for kittens at about 10 weeks old, ie post weaning, then optionally at 16 weeks especially for pedigree cats or if disease is endemically severe. A booster is advised at 15 months old, then every 3 years thereafter or according to individual assessment. Feline Leukemia vaccine given twice, 3 weeks apart, before the kitten turns 4 months old, if the cat is likely to go outside and/or contact feline leukemia carrying cats. Due to the incidence of post vaccine sarcoma formation, and the longevity of feline leukemia titres in most cats, it is not advisable to vaccinate any cat over 4 months of age for leukemia. This paper did not advise the use of chlamidia, giardia or bordatella vaccines for cats. (See AVA Annual conference Adelaide 2002 ASAVA Proceedings - in file). An option would be to have an annual recall of cats and rotate monovalent triennial vaccines, eg feline enteritis vaccine only at 2 years, feline calicivirus vaccine only at 3 years, feline herpes virus vaccine only at 4 years, then keep repeating cycle. As with canine vaccines, we would need to request single (monovalent) feline vaccines be manufactured to allow this improved vaccination program. Also, as with canine vaccination, simple titer testing of Australian cats would prove or not whether these above suggestions are worth adopting as recommended policy for Australian veterinarians. General Rules for Vaccination
References for adverse reaction to canine vaccines
References for adverse reaction to feline vaccines.
References for possible vaccine induced increase in disease incidence.
References for infectious disease epidemiology and homoeopathic disease prevention.
There are many other relevant references in the Vaccination data file - tel 0403180567 to hire a copy. This discussion paper was written by Dr Clare Middle, based on a literature review carried out by Dr Charissa Smith, in collaboration with the committee and members of the Australian Association of Holistic Veterinarians, plus data searched by Ms Pat Styles. |