There is much confusion in the general public about the duration of immunity of canine vaccines. Below is a copy of my testimony and model disclosure submitted to Maine's Agriculture Committee in support of LD 429, the nation's first pet vaccine disclosure legislation, which was introduced on my behalf by Representative Peter Rines of Wiscasset. Anyone who wishes to have copies of the attachments referenced below, please e-mail me at [email protected]
Duration of Immunity to Canine Vaccines: What We Know and Don't Know, Dr. Ronald Schultz http://www.cedarbayvet.com/duration_of_immunity.htm
The 2003 American Animal Hospital Association's Canine Vaccine Guidelines are accessible online at http://www.leerburg.com/special_report.htm .
The 2006 American Animal Hospital Association's Canine Vaccine Guidelines are downloadable in PDF format at http://www.aahanet.org/PublicDocumen...s06Revised.pdf .
February 27, 2005
TO: The Agriculture, Conservation and Forest Committee
RE: LD 429, An Act to Require Veterinarians to Provide Vaccine Disclosure Forms
My name is Kris Christine and I live with my family in Alna, Maine. Before I begin my testimony, I’d like to advise the committee that one of the world’s leading veterinary research scientists, Dr. W. Jean Dodds, wanted to be here today to testify in support of LD429, but could not do so because of prior commitments. With her permission, in the attachments to my testimony, I have included her letter to Representative Peter Rines dated February 17, 2005 (Attachment 5) resolutely endorsing this first-in-the-nation veterinary vaccine disclosure legislation.
I am here today to respectfully urge this committee to recommend passage of LD429 – An Act to Require Veterinarians to Provide Vaccine Disclosure Forms because pet owners need the scientifically proven durations of immunity (how long vaccines are effective for) in order to make informed medical choices for their animals.
Many Maine veterinarians have failed to inform clients that most core veterinary vaccines protect for seven or more years, and pet owners, unaware that their animals don’t need booster vaccinations more often, have unwittingly given their companions useless booster shots – taking an unnecessary toll on their finances and animals’ health. The human equivalent would be physicians vaccinating patients against tetanus once every year, two years, or three years and not disclosing that the vaccines are known to be protective for 10 years.
For years veterinarians have sent pet owners annual, biennial and triennial reminders for redundant booster shots and justified it with vaccine manufacturers’ labeled recommendations. According to the American Veterinary Medical Association’s (AVMA) Principles of Vaccination (Attachment 6), “..revaccination frequency recommendations found on many vaccine labels is based on historical precedent, not on scientific data … [and] does not resolve the question about average or maximum duration of immunity [Page 2] and..may fail to adequately inform practitioners about optimal use of the product…[Page 4] .” As the Colorado State University Veterinary Teaching Hospital states it: “…booster vaccine recommendations for vaccines other than rabies virus have been determined arbitrarily by manufacturers.”
Dr. Ronald Schultz, Chairman of Pathobiological Sciences at the University of Wisconsin School of Veterinary Medicine, is at the forefront of vaccine research and is one of the world’s leading authorities on veterinary vaccines. His challenge study results form the scientific base of the American Animal Hospital Association’s (AAHA) 2003 Canine Vaccine Guidelines, Recommendations, and Supporting Literature (Attachment 7). These studies are based on science – they are not arbitrary. The public, however, cannot access this data. The American Animal Hospital Association only makes this report available to veterinarians, not private citizens, and Maine’s pet owners are unaware that the AAHA Guidelines state on Page 18 that: “We now know that booster injections are of no value in dogs already immune, and immunity from distemper infection and vaccination lasts for a minimum of 7 years based on challenge studies and up to 15 years (a lifetime) based on antibody titer.” They further state that hepatitis and parvovirus vaccines have been proven to protect for a minimum of 7 years by challenge and up to 9 and 10 years based on antibody count. So, unless the Legislature passes LD429 requiring veterinarians to provide vaccine disclosure forms, dog owners who receive an annual, biennial, or triennial reminders for booster shots will not know that nationally-accepted scientific studies have demonstrated that animals are protected a minimum of 7 years after vaccination with the distemper, parvovirus, and adenovirus-2 vaccines (see Page 12 AAHA 2003 Guidelines attached, and Table 1, Pages 3 and 4).
"My own pets are vaccinated once or twice as pups and kittens, then never again except for rabies,” Wall Street Journal reporter Rhonda L. Rundle quoted Dr. Ronald Schultz in a July 31, 2002 article entitled Annual Pet Vaccinations may be Unnecessary, Fatal (Attachment 2). Dr. Schultz knows something the pet-owning public doesn’t – he knows there’s no benefit in overvaccinating animals because immunity is not enhanced, but the risk of harmful adverse reactions is increased. He also knows that most core veterinary vaccines are protective for at least seven years, if not for the lifetime of the animal.
The first entry under Appendix 2 of the AAHA Guidelines (Attachment 7) “Important Vaccination ‘Do’s and Don’ts” is “Do Not Vaccinate Needlessly – Don’t revaccinate more often than is needed and only with the vaccines that prevent diseases for which that animal is at risk.” They also caution veterinarians: “Do Not Assume that Vaccines Cannot Harm a Patient – Vaccines are potent medically active agents and have the very real potential of producing adverse events.” Very few pet owners have had this disclosed to them.
The AVMA’s Principles of Vaccination (Attachment 6) states that “Unnecessary stimulation of the immune system does not result in enhanced disease resistance, and may increase the risk of adverse post-vaccination events.” (page 2) They elaborate by reporting that: “Possible adverse events include failure to immunize, anaphylaxis, immunosuppression, autoimmune disorders, transient infections, and/or long-term infected carrier states. In addition, a causal association in cats between injection sites and the subsequent development of a malignant tumor is the subject of ongoing research.”(Page 2)
Referring to adverse reactions from vaccines, the Wall Street Journal article cited above (Attachment 2) reports: “In cats there has been a large increase in hyperthyroidism and cancerous tumors between the shoulder blades where vaccines typically are injected.” With modified live virus vaccines (distemper, parvovirus, hepatitis), some animals can actually contract the same disease which they are being inoculated against. If the public knew an animal’s immunity to disease is not increased by overvaccination, they would certainly not consent to expose their pets to potential harm by giving them excessive booster shots
Veterinary vaccines are potent biologic drugs – most having proven durations of immunity much longer than the annual, biennial or triennial booster frequencies recommended by vaccine manufacturers and veterinarians. They also carry the very real risk of serious adverse side affects and should not be administered more often than necessary to maintain immunity.
The extended durations of immunity for vaccines is not “new” or “recent” science as some members of the Maine Veterinary Medical Association (MVMA) have claimed. AAHA reveals on Page 2 of their Guidelines that ideal reduced vaccination protocols were recommended by vaccinology experts beginning in 1978. A Veterinary Practice News article entitled “Managing Vaccine Changes” (Attachment
3) by veterinarian Dennis M. McCurnin, reports that: “Change has been discussed for the past 15 years and now has started to move across the country."
According to a September 1, 2004 article in the DVM veterinary news magazine (Attachment 1), the 312 member Maine Veterinary Medical Association (MVMA) “champions full disclosure of vaccine
information to pet owners.” MVMA president, Dr. Bill Bryant, is quoted as stating: “Its time for something like this to come out … disclosure forms will be an important resource to have available, [and] if it goes before the Legislature, we’d likely support it.”
It is time. Pet owners have the right to know the scientifically proven durations of immunity for the veterinary vaccines given their animals, as well as the potential adverse side effects and benefits. LD 429 would make that standardized information available to all pet owners.
Kris L. Christine
MODEL CANINE CORE VACCINE DISCLOSURE FORM
Prepared by Kris L. Christine
Vaccines have played a significant role in enabling animals to live longer and healthier lives. Thorough evaluations of the risks of the disease, and those potentially associated with the vaccine, compared to the benefits of vaccination for the patient, are necessary in crafting optimal health recommendations that include vaccination.
The proper application of vaccines to animal populations has enhanced their health and welfare, and prolonged their life-spans. The risks to animal health from non-vaccination are significant. However, vaccination is a potent medical procedure associated with both benefits and risks for the patient. Adverse events, including some that are potentially severe, can be unintended consequences of vaccination. Because vaccinating an animal which is already immune to a disease does not increase their immunity, but does expose them to the risk of adverse reactions, it is important to avoid overvaccination. Blood titers can help determine whether an animal’s antibody count is at protective levels.
The risks associated with the core canine diseases are as follows:
1. Distemper – high rates of morbidity and mortality from respiratory, gastrointestinal and neurological abnormalities; a widespread disease
2. Parvovirus – high rates of morbidity and mortality resulting primarily from gastrointestinal disease; this disease has worldwide distribution;
3. Canine Adenovirus – high rates of morbidity and mortality from liver dysfunction
4. Rabies – nearly universally fatal neurological disease. Infected animals are a potential source for human infection, thus vaccination is mandated by law in most states.
The risks associated with vaccination are as follows:
Possible adverse events from vaccination include failure to immunize, anaphylaxis, immunosuppression, autoimmune disorders such as hyper/hypothyroidism, polyarthritis, allergies, transient infections, and/or long-term infected carrier states. In addition, a causal association in cats between injection sites and the subsequent development of a malignant tumor is the subject of ongoing research.
Optimal immune responses are obtained by vaccines administered singly three to four weeks apart rather than in combination shots. Single vaccine administration also reduces the likelihood of adverse events as well as increasing the animal’s immune response. Only healthy animals should be vaccinated.
Except for the rabies vaccine, manufacturers’ labeled revaccination recommendations are based on limited scientific data and do not contain information on the vaccine’s maximum duration of immunity. The tables below contain the minimum duration of immunity data from the canine vaccine studies performed by Dr. Ronald Schultz, Professor and Chair of the Pathobiological Sciences Department at the University of Wisconsin School of Veterinary Medicine, which form the scientific base of the American Animal Hospital’s 2003 Canine Vaccine Guidelines, Recommendations, and Supporting Literature.
If your animal experiences any of the following symptoms after vaccination, you should contact your veterinary care provider immediately: fever, vomiting, diarrhea, uncontrollable trembling, lack of coordination, seizures or a hard lump at the vaccination site which doesn’t disappear after a couple of weeks.
Table 1: Minimum Duration of Immunity for Canine Vaccines
Vaccine Minimum Duration Methods Used to
Of Immunity Determine Immunity
Canine Distemper Virus (CDV)
Rockborn Strain 7 years/15 years challenge/serology
Onderstepoort Strain 5 years/9 years challenge/serology
Canine Adenovirus-2 (CAV-2) 7 years/9 years challenge-CAV-1/serology
Canine Parvovirus-2 (CPV-2) 7 years challenge/serology
Canine Rabies 3 years/7 years challenge/serology
Data from Duration of Immunity to Canine Vaccines: What we know and Don’t Know by Dr. Ronald D. Schultz, Professor and Chair, Department of Pathobiological Sciences at the University of Wisconsin School of Veterinary Medicine.
Note: Challenge studies are those in which an animal is vaccinated, isolated for a number of years, and then injected with high doses of virulent virus to test its immunity to disease. Serology is the method of counting antibody levels in the blood to determine an animal’s immunity.
Kris L. Christine
The Rabies Challenge Fund