TO VACCINATE OR NOT TO VACCINATE?

Vaccination is a controversial subject in the veterinary profession these days. What has been widely accepted as the “yearly shot” has been called into question not just in the holistic veterinary community, but in the larger scientific community, including veterinary colleges and organizations such as the American Animal Health Association and the Association of Feline Practitioners.

EVIDENCE FOR YEARLY VACCINATIONS

Evidence against yearly vaccination is difficult to ignore. The vaccine manufacturers reluctantly admit that there is no scientific evidence for yearly vaccination, although testing to determine the duration of immunity for vaccinations has been slow in coming. Dr. Ron Schultz., Ph.D. and Tom Phillips, DVM wrote in the Current Veterinary Therapy XI that immunity to viruses persists for years or for the life of the animal. Dr. Schultz studied the feline viruses in a controlled environment and found that vaccinated cats with no exposure to the viruses had virtually lifelong immunity. Following this study the Association of Feline Practitioners came out with recommendations to vaccinate every 3 years. Distemper antibodies have been found in dogs that have had puppy vaccines only, giving evidence that this vaccine gives lifelong immunity. Most veterinary clinics have not adopted the guidelines that many university veterinary hospitals have adopted, such as alternating vaccines so that animals get each vaccine every 3 years instead of yearly.

WHICH VACCINES ARE CONSIDERED CORE VACCINES?

Most people are not aware that some vaccines are considered core vaccines and others are considered optional. Core vaccines in cats include panleukopenia/distemper, feline rhinotracheitis, herpes virus and calici virus. Non-core vaccines are chlamydia, feline leukemia, feline infectious peritonitis. Core vaccines in dogs are parvovirus and distemper. Although most vaccines have canine adenovirus and parainfluenza virus in them, these do not represent significant clinical disease. Corona virus is often used to dilute the vaccine and this disease is a mild self-limiting diarrhea, if it is a disease at all.
Leptospirosis, Lyme, Giardia and Bordatella are all optional vaccines. Rabies is required to cross the border and for public health reasons but there is virtually no risk of a domestic animal contracting rabies in the lower Mainland and most of the west coast.

PROBLEMS WITH OVER-VACCINATION?

Many people, including some veterinarians, seem to believe that the more the better. If we can protect our pets against these diseases, even if the potential risk is relatively low, why not? The problem with vaccination, as well as any drug or chemical that enters the bloodstream directly, is that the results will not only be beneficial. Vaccines stimulate the immune system and sometimes this can happen in unpredictable ways. Vaccination has been linked to such devastating diseases as immune-mediated anemia and thrombocytopenia, diseases in which the immune system turns against the body’s own cells. Although a direct link is difficult to prove, the increase in immune-mediated disease has been too difficult to ignore. From allergic skin conditions to inflammatory bowel disease to arthritis, it seems that the immune system becomes hyper-reactive and no longer can distinguish between outside foreign agents and its own cells. Often these diseases come on, or flare up, within months of vaccinations. In other cases, the link is not so direct and thus is difficult to prove. The evidence does seem to point to the fact that vaccinations are not benign and they most likely cause a slow, progressive, malfunctioning of the immune system. Don Hamilton, in his book Homeopathic Care for Cats and Dogs suggests that in vaccinating we are simply exchanging acute disease for chronic disease. In the big picture this is rather convincing. Although we see an occasional outbreak of infectious disease, overall the majority of veterinary practice these days is treating chronic degenerative disease and immune-system problems.

ALTERNATIVES TO VACCINATION?

First, we have to ask ourselves the following questions when we chose whether or not to vaccinate:

1. Is the disease serious or life threatening in this animal?
2. Will there be a good chance that the animal will be exposed?
3. Is this vaccine known to be effective?
4. Is this vaccine known to be safe?

Basically, we should do a risk assessment for each individual animal we vaccinate. What is the risk of the animal getting the disease vs. the risk of the animal having a problem from the vaccine. For example, a strictly indoor cat has a zero risk of getting feline leukemia but an estimated 1/10 000 risk of getting a tumour from the injection.
Alternatives to vaccines do exist. Antibody titres can be done to check if your animal has good immunity to most viruses. Although false negatives can occur ? meaning that the antibody may not be detectable although immunity is still present ? a good titre can give some degree of confidence that the animal is protected.

Of course, a good diet and preventative health check-ups are key to good health and making sure that if your cat or dog does have exposure to an infectious disease they will be able to mount a good immune response. An example of this is Giardia. Giardia is a parasite that can be contracted from dirty water. Healthy animals will not get clinically ill, or will respond quickly to treatment. A giardia vaccine has come out recently and it seems like a backwards solution to a simple problem.
There is an abundance of information out there, in both the veterinary as well as human literature on the pros and cons of vaccination. Please make an informed decision when it comes time for the yearly shot.