. Did you know your dog’s (and your cat’s) vaccines last a lot longer than 3 years?

The duration of immunity for Rabies vaccine, Canine distemper vaccine, Canine Parvovirus vaccine, Feline Panleukopenia vaccine, Feline Rhinotracheitis, feline Calicivirus, have all been shown to last a minimum of 7 years by serology (measuring blood antibody levels) for rabies and challenge studies for all the rest.

In the Duration of Immunity to Canine Vaccines: What We Know and What We Don’t Know, Proceedings – Canine Infectious Diseases: From Clinics to Molecular Pathogenesis, Ithaca, NY, 1999,  Dr Ronald Schultz, a veterinary immunologist at the forefront of vaccine research and chair of the University of Wisconsin’s Department of Pathobiological Sciences, outlines the duration of immunity for the following vaccines:

Minimum Duration Of Immunity For Canine Vaccines 

Distemper- 7 years by challenge/15 years by serology
Parvovirus – 7 years by challenge/ 7 years by serology
Adenovirus – 7 years by challenge/ 9 years by serology
Canine rabies – 3 years by challenge/ 7 years by serology

Dr Schultz concludes: “Vaccines for diseases like distemper and canine parvovirus, once administered to adult animals, provide lifetime immunity.”  (Are we vaccinating too much JAVMA, No. 4, August 15, 1995, pg. 421)

Yet vets continue to vaccinate annually. Dog owners feel that their vets are doing their dogs a great service by vaccinating every three years instead of annually – why do we allow it when these studies were done over thirty years ago and have been replicated time and again by other researchers?

Vaccines for diseases like distemper and canine parvovirus, once administered to adult animals, provide lifetime immunity.
- Immunologist Dr Ronald Schultz

Ian Tizard states:  “With modified live virus vaccines like canine parvovirus, canine distemper and feline panleukopenia, calicivirus, and rhinotracheitis the virus in the vaccine must replicate to stimulate the immune system. In a patient that has been previously immunized, antibodies from the previous vaccine will block the replication of the new vaccinal virus. Antibody titers are not significantly boosted. Memory cell populations are not expanded. The immune status of the patient is not enhanced.

After the second rabies vaccination, re-administration of rabies vaccine does not enhance the immune status of the patient at one or two year intervals.  We do not know the interval at which re-administration of vaccines will enhance the immunity of a significant percentage of the pet population, but it is certainly not at one or two year intervals. Tizard Ian, Yawei N, Use of serologic testing to assess immune status of companion animals, JAVMA, vol 213, No 1, July 1, 1998.

“The recommendation for annual re-vaccination is a practice that was officially started in 1978.”  says Dr. Schultz.  “This recommendation was made without any scientific validation of the need to booster immunity so frequently. In fact the presence of good humoral antibody levels blocks the anamnestic response to vaccine boosters just as maternal antibody blocks the response in some young animals.

He adds:  “The patient receives no benefit and may be placed at serious risk when an unnecessary vaccine is given. Few or no scientific studies have demonstrated a need for cats or dogs to be revaccinated. Annual vaccination for diseases caused by CDV, CPV2, FPLP and FeLV has not been shown to provide a level of immunity any different from the immunity in an animal vaccinated and immunized at an early age and challenged years later. We have found that annual revaccination with the vaccines that provide long-term immunity provides no demonstrable benefit.”

Why then, have vets not embraced the concept of lifelong immunity in dogs?

“Profits are what vaccine critics believe is at the root of the profession’s resistance to update its protocols. Without the lure of vaccines, clients might be less inclined to make yearly veterinary visits. Vaccines add up to 14 percent of the average practice’s income, AAHA reports, and veterinarians stand to lose big.  I suspect some are ignoring my work,” says Schultz, who claims some distemper vaccines last as long as 15 years. “Tying vaccinations into the annual visit became prominent in the 1980s and a way of practicing in the 1990s. Now veterinarians don’t want to give it up.”

The report of the American Animal Hospital Association Canine Vaccine Taskforce in JAAHA (39 March/April 2003)3 includes the following information for vets: 

 This is supported by a growing body of veterinary information  as well-developed epidemiological vigilance in human medicine that indicates immunity induced by vaccination is extremely long lasting and, in most cases, lifelong.’

Both the AAHA and the AVMA must do more to “step up to the plate” says noted immunologist, Dr. Richard Ford. But the reality is the vets do not have to listen to the AAHA or the AVMA and it appears the state veterinary medical boards are not interested in enforcing vaccine schedules, opting to leave it up to the individual vet.

Dr Bob Rogers hired a Chicago based law firm and initiated a class action suit for pet owners who were not given informed consent and full disclosure prior to vaccination administration. His article entitled “The Courage to Embrace the Truth”, states “While attending conferences like WSVMA and NAVMC I have asked over 400 DVMs from various parts of the country if they attended the seminars on New Vaccination Protocols. I was told by all but one, “I don’t care what the data says, I am not changing.” One DVM here on VIN even said “I am not changing until the AVMA makes me change.”