Current Thoughts on Shots

Even conservative veterinary practitioners and schools are reducing their recommended vaccination schedules for puppies and dogs—here’s why.

By Pat Miller

Modern-day dog owners enjoy the comforting certainty that their puppies can and will be given a series of vaccinations, so-called "puppy shots," to protect them from life-threatening canine diseases such as distemper, parvovirus, and rabies. Most of us were indoctrinated in early childhood to schlep Shep to the vet once a year for his annual booster shots in order to extend that vital protection year after year. We accepted without question that a failure to do so was the height of dog owner irresponsibility. We wouldn't dream of leaving our beloved canine companions at the mercy of the multitudes of evil distemper, hepatitis, leptospirosis, parainfluenza, parvovirus, coronavirus, Lyme, and Bordetella germs and viruses that lurk in the environment. Faithfully following our veterinarians' instructions, we vaccinate our dogs year in and year out; confident this is "the best thing" for them.  But according to some veterinary immunologists, sometimes, we actually may do more harm than good by immunizing our furry friends.

Many holistic veterinarians think that by injecting our dogs every year with what we believe to be life-saving substances, we are actually destroying their immune systems, and condemning them to a life of vaccine-induced allergies, behavior problems, encephalitis, epilepsy, cancer, and a laundry list of autoimmune diseases including Addison's disease, rheumatoid arthritis, Hashimoto's thyroiditis, systemic lupus erythematosus  (SLE), hemolytic anemia, hepatitis, diabetes, Grave's disease, hypoparathyroidism, uveitis, and more. They insist that vaccines actually cause more problems than they prevent, and that dogs are dying by the thousands of vaccinosis" - a morbid reaction to vaccines.  Some even go so far as to suggest that we should never vaccinate. Who are we supposed to believe?

What is a vaccine?
As most of us know, vaccines are adminis­tered for the purpose of establishing resistance to an infectious disease. A suspension of infectious agents (or some part of them) is injected into the dog in order to stimulate the immune system to produce antibodies to the disease. If the dog is later exposed to the disease, the antibodies quickly react to attack and destroy the virus.

Vaccines come in two types: killed virus and modified live (or attenuated) virus (MLV). Killed vaccines are mixed with a substance called an adjuvant to make them more effective. They often require more injections to accomplish immunization, and various adjuvants are suspected of causing allergic reactions. The modified live vaccines generally work more quickly, but are more likely to cause suppression of the immune system.  Many people assume that vaccines are 100 percent effective in preventing disease. Unfortunately, this is far from true. There are many reasons why a vaccine might not be effective in a given case.

Some researchers regard some "puppy shots" as unnecessary and even potentially harmful. There is a great deal of controversy - and little solid research -about safe vaccination schedules for puppies and dogs.

The first reason has to do with the animal itself rather than the vaccine; it is the response of the vaccinated animal's immune system that determines the effectiveness of the vaccine. If a dog is sick, weak, or malnourished, his body may be unable to mount the proper defense. If his immune system is depressed due to previous disease, surgery, poor genes, old age or drug therapy, vaccinations are likely to be ineffective. Every vaccine package lists warnings against vaccinating any animal whose immune system may be compromised, and most veterinarians will agree that a sick dog should not be vaccinated.

Puppies present their own challenges to thorough vaccination: If a puppy is young, his mother's antibodies may still be in his system and interfere with the pup's ability to respond to the vaccine. This is why we give a series of puppy shots - to span the period of time when he may or may not be protected by his mother's immunities.  In addition, if a vaccine has been improperly produced, poorly handled (for example, not kept properly refrigerated), incorrectly administered (i.e., given subcutaneously when it is supposed to be given intramuscularly) or given on a faulty schedule, it may be rendered ineffective.

Not always safe
Most veterinarians tend to reassure their clients that vaccinations are perfectly safe. This is not always true. A relatively small percentage of dogs can have an acute anaphylactic (severe allergic) reaction to one or more vaccines. When this happens, prompt administration of adrenaline, epinephrine, antihistamines, or corticosteroids may be necessary to save the dog's life. Milder reactions, such as soreness and swelling at the injection site, lack of appetite, and general lethargy and depression can also occur within a day or two following administration of the vaccine. In addition, there is a growing body of evidence that vaccines are sometimes associated with immune system problems.

Off to the left side of the issue are vaccine alarmists, who claim that, far from being safe, vaccines damage immune systems in a large percentage of dogs, causing more diseases than they prevent. For example, in her book, What Vets Don't Tell You About Vaccines, Catherine O'Driscoll says that vaccines are deadly poisons that disarm and unbalance the immune system, and suggests that they should rarely, if ever, be used.

Then there are the vaccine moderates, including W. Jean Dodds, DVM, a 1964 graduate of the Ontario Veterinary College. From 1965 to 1985, Dodds conducted comparative studies of animals with inherited and acquired blood diseases while working for the New York State Health Department. In 1986 she opened Hemopet, the first nonprofit national blood bank for animals, which she continues to operate to this day in Southern California. On behalf of Hemopet she consults in clinical pathology nationally and internationally, and is known as one of the country's leading experts on hematology and blood banking, immunology, endocrinology, and nutrition.   Dodds has identified a long list of breeds and families within breeds who are genetically predisposed to immune system sensitivities. The breed list includes Dobermans, Rottweilers, Yorkshire terriers, Akitas, Standard poodles, Great Danes, Weimaraners, and American Eskimos.  "The vaccine," says Dodds, "is just a precipitating event. It does not create the weak immune system. For dogs predisposed to immune system problems, toxic exposure, overheating, poor diet, or some other condition that stresses the system can also be precipitating events.  "For the last 20 years," she continues, "We have been increasingly aware that vaccines are associated with autoimmune disease. But vaccines have played a vitally important role in reducing severe infectious diseases in our companion animals. Because of this, we are seeing more adverse reactions than infections, and some people are tempted to cease vaccinating altogether. This is not wise. The diseases still exist, and it makes sense to vaccinate, when safe, in order to protect our pets and the pet population in general. A well-nourished, healthy animal should not have problems with the standard vaccines. We do need to identify high-risk animals and modify our vaccination protocols to meet their individual needs when appropriate in order to minimize their risk."

Dr. Susan G. Wynn, a private practitioner in Marietta, Georgia, has done teaching in alternative medicine, co-edited a text for veterinary schools entitled Complementary and Alternative Veterinary Medicine, and completed a four-year post-doctoral fellowship in viral immunology. She agrees with Dr. Dodds.   "There is no question that vaccines are more beneficial than harmful," she says. "Distemper used to kill some 50 percent of all dogs born. I have seen a total of three cases of distemper since my 1987 graduation. Vaccines have played a really important role in reducing the incidence of severe, infectious diseases. They have been so effective that today we do see more adverse vaccine reactions than the infections themselves, which may give the appearance that the vaccine is worse than the disease. This is simply not the case. Ceasing all vaccinations would be foolhardy. Our challenge is to reduce vaccines to the least needed to prevent harm, while maintaining our current high level of protection against infectious diseases."

Still, veterinarians have a legal and ethical obligation to inform their clients of the relative benefits and risks of vaccines so that pet owners can make informed choices regarding their animals' medical care. There are times when not vaccinating may well be the wise, educated decision.

No ideal frequency
Vaccine manufacturers have long counseled against vaccinating dogs who are pregnant or those who are not healthy. But they do promote annual vaccination protocols, and they clearly reap monetary benefits from the widely accepted United States Department of Agriculture (USDA) recommendation issued 25-30 years ago supporting annual vaccinations. It is disturbing to discover that the USDA recommendation is not based on any scientific evidence. In fact, no scientific studies have ever been done to determine the optimum frequency of vaccinations. The annual booster policy was instituted in large part so pet owners would be prompted to bring their dogs in for an annual well-pet check-up, allowing veterinarians to find and treat other conditions promptly.

Many dog owners are shocked to learn that no studies have ever determined the optimum frequency of vaccinations. The annual booster policy was instituted in large part so pet owners would be prompted to bring their dogs in for an annual well-pet check-up, allowing veterinarians to find and treat other conditions promptly.

In Dr. Dodds' opinion, vaccinating dogs annually against all the diseases that exist is too much. "While there will probably never be a study to definitively identify the effective length of vaccines because of the immense cost involved, a recent study we completed of 1200 dogs demonstrated that one to two years after the initial immunization, 94.4 percent of the dogs still had adequate immunities to parvovirus, and 97.3 percent were still protected against distemper. Some dogs were tested as long as six years after the vaccination, with similar results."

This study and resulting discussions about its data seems to have initiated change within the veterinary community. In perhaps the most significant move seen in the industry, the American Veterinary Medical Association (AVMA) has published several papers supporting a move to three-year protocols. Many veterinarians and an increasing number of veterinary schools are rewriting their vaccination protocols to recommend three-year intervals between shots rather than annual boosters.

Colorado State University's College of Veterinary Medicine is one of these. Their revised protocol statement says, "Our adoption of this routine vaccination program is based on the lack of scientific evidence to support the current practice of annual vaccination and increasing documentation showing that over vaccinating has been associated with harmful side effects."   CSU now recommends the standard puppy series, a booster one year later, then vaccinations every three years after that. Since over-vaccinating can be a trigger for immune system problems, why vaccinate any more than necessary? (See "Dr. W. Jean Dodds' Revised Vaccination Protocol)

Vaccination contraindications
Drug companies and veterinarians agree that sick and pregnant dogs should not be vaccinated.

The definition of "sick," however, is left open to wide interpretation. Dr. Dodds and Dr. Wynn both advise not vaccinating in the following circumstances:

• If the dog is elderly

• If the dog is pregnant

• If the dog has symptoms of any illness, mild or severe, including everything from low-grade chronic disease such as skin conditions to cancer

• If the dog has any other medical condition, including lameness

• If the dog is undergoing surgery

• If the dog is on any immune-suppressant drugs

Many holistic veterinarians advise against vaccinating older dogs. After a lifetime of annual vaccinations, they are probably already well protected against infectious diseases. In addition, the vaccines may stress the elderly dog's weakening immune system.

Clearly, this list encompasses a much broader range of animals than does "sick or pregnant." In general, if there is any question about the dog's health status, it is better to postpone vaccination until the dog is clearly healthy.  In addition to not vaccinating some dogs, there are a number of other ways to reduce the risk of vaccine-related problems:

• Measure antibodies through titer tests and only revaccinate when indicated by low titers, OR...

• Reduce the incidence of booster shots to every three years after the first annual booster.

• Give individual vaccines instead of combined (such as DHLPPC), and don't give several shots at one time.

• Watch your dog closely for several weeks following vaccination to look for any reactions that might influence your future vaccination decisions. ANY health problems following vaccination should be noted, whether the reaction is a hot spot outbreak, an ear infection, or something more dramatic, such as an epileptic seizure. It may be wise not to administer the same vaccine at any time in the future to a dog that reacts to the shot one or more times.

• Don't vaccinate for Bordetella, corona virus or Lyme disease unless these diseases are endemic locally or in a specific kennel.

• Do not deworm or initiate new medicines at time of vaccination, and avoid the use of toxic flea and tick control products.

• Only vaccinate against diseases for which your dog is at risk (usually rabies, parvo and distemper). There have not been any reported cases of canine hepatitis in a very long time, and the leptospirosis vaccine is not effective against current prevalent strains that produce this disease. It is the leptospirosis vaccine that is most commonly associated with acute anaphylactic reactions in dogs.

Little support for nosodes
Nosodes are a homeopathic alternative to vaccinations, in which a small amount of the infectious agent is potentized in water (by vigorous shaking) and then diluted to such a degree that there is no longer any measurable amount of the agent in the liquid. Some holistic veterinarians believe nosodes to be effective in preventing disease. Others, including Dr. Wynn, are reluctant to place much faith in them.  "While they are certainly not harmful and perhaps they are beneficial, there is no scientific evidence to support their effectiveness," says Dr. Wynn. "In fact, there is at least one study that clearly showed nosodes to be ineffective against parvovirus."

No easy answer
As much as we all want easy answers to the vaccination question, there aren't any. Even the revised vaccine protocols are general guidelines, not bibles for every dog. Here, at least as much as in any other aspect of our relationships with our four-footed companions, the holistic approach is critical. We must know our dog well and weigh all of the benefits and risks of vaccination in light of his unique self in order to be able to make the best decisions about what vaccination program is best for her.

Above all, whether in training, management or veterinary care, don't ever let anyone convince you to do something to your dog that you know is wrong. You are his guardian and bear the ultimate responsibility for making the best choices for his well being. As you wander through the forest of information and half-truths about vaccines and diseases, be sure to make your choices carefully and well.

Pat Miller, a trainer and writer from Salinas, California, is a regular contributor to WDJ.