The Lay Person’s Guide to Canine Vaccination
By Cynthia Roethel
This is a summary of an article written by Dr. Richard B. Ford, who was an integral part of the Canine Vaccine Task Force that published the new vaccination guidelines and recommendations in 2003.
How and when you vaccinate your dog is a decision that you and your veterinarian make together. Your veterinarian and you make up a “health care partnership” whose only goal is the health and welfare of your dog. You can contribute to this partnership by being as well informed about vaccinations, their benefits and their side effects as you possibly can.
While the guidelines published by the task force were not designed to be enforceable statutes that every veterinarian should follow, they have, without a doubt, become the “templates for the standard of care” in the United States. Dr. Ford is emphatic and states every veterinary practitioner should take a hard look at what vaccines are administered and at what stage of life they are given. To merely accept all vaccines and make them part of a routine protocol in all situations is simple WRONG. Yet, it happens. Too often decisions to immunize and how often has been based on marketing literature, continuing education programs and anecdotal opinions from veterinary associates. We are reminded that there was never any scientific data that supported the requirement for annual boosters.
Dr. Ford comments that many practitioners now send out “annual wellness examination” reminders while others still send out “annual booster” reminders. It was a concern of many veterinarians that not giving boosters annually would cause a general decline in health because they would not have the opportunity to examine their clients annually. So the issue was not really whether to vaccinate every year or every three years but rather whether clients received their annual examinations. Every owner owes it to his or her dog to have them examined annually and, if appropriate, vaccinations can be given then.
Giving boosters every three years is not a hard and fast rule. The guidelines do not say vaccinations should be given every three years ONLY but rather recommend that it is not necessary to give them every year. Keep in mind that the frequency of rabies vaccinations is dictated by states and municipalities and a few require annual rabies vaccinations. The Vaccination Guidelines in no way suggest violating local statutes.
Vaccines are divided into two general categories: CORE and NON-CORE. CORE vaccines are those that are recommended for every dog.
Vaccines are determined to be CORE by (1) the severity of the disease they prevent, (2) the risk of transmissibility of the disease to susceptible animals, and (3) the potential for the disease to be transmitted to humans.
NON-CORE vaccines are those that are recommended for clients when there is a known or likely risk of exposure or if the client’s lifestyle might suggest a risk of infection. Lyme borreliosis vaccine is an example of this. If Lyme is a concern in your area of the country, then it might be appropriate to vaccinate against it. Again, the Vaccination Guidelines do not mandate which vaccines should be CORE or NON-CORE. The follow table shows the Vaccination Guideline recommendations for CORE and NON-CORE vaccines and their minimum duration of immunity.
TABLE 1: Types of Vaccines Licensed for use in Dogs (From: “Vaccines and Vaccinations: The Road Ahead,” by Dr. Richard B. Ford. Reproduced with Dr. Ford’s permission.
NR = Not Generally Recommended
Dr. Ford discussed antibody titers versus annual vaccination and does not recommend them as a routine. He sites several factors:(1) Serum antibody titers to a particular agent of disease, especially viruses, are a relatively crude laboratory method. He reminds us that that antibody concentration is not necessarily the same as immunity. While a positive titer to canine distemper or canine parvovirus correlates with protection, a negative titer does not necessarily mean susceptibility. There might not be a need to vaccination a dog with a negative titer, as cell-mediated immunity is the principle response needed to prevent disease and cell-mediated immunity cannot be evaluated with titers. (2) There are no standarized laboratory methods for determining antibody concentrations in the United States. So results from one laboratory can differ significantly from another. (3) The titers that are routinely available are canine distemper and canine parvovirus. Titers for other vaccines are not routinely available. While they could be developed, again the correlation between antibody titer and immunity is not well defined, if at all. (4) The more titers practitioners do, using reliable labs, the sooner it becomes apparent that titers do, in fact, persist and continued testing is not necessary. There are wonderful studies that support this.
Changing the ritual “annual booster” thought processes has been a great challenge. Veterinary medicine has not done anything wrong over the years by giving boosters annually. Just as diagnostics have advanced in veterinary medicine, so have methods of evaluating the efficacy of therapeutic or prophylactic agents. The recommendations for three-year intervals for some vaccines are based on today’s knowledge and are predominantly based on studies supported in part by information on persistent antibody titers. Recent studies show that immune response persists for several years following vaccination and routinely giving annual boosters is not necessary.
Vaccine safety and adverse reactions are pivotal in Dr. Ford’s recommendations to serious rethink vaccination protocols. While immune-mediated diseases resulting from vaccinations are thought to be uncommon, there is serious lack of supporting data. Part of the problem is that there is no mechanism in place that allows for the reporting of reactions, how often they occur and if a certain product is associated with the reaction. The USP’s Veterinary Practitioner Reporting Program was discontinued in the Spring of 2003. I, personally, had thought that the USDA had some sort of process in place for reporting adverse reactions, but Dr. Ford corrected my thinking at a recent seminar I attended.
In dogs, adverse reactions to vaccinations can include injection-site granuloma. More acute reactions include itching and swelling of the face, muzzle and ears. Occasionally reactions can be severe, but are rarely associated with cardiovascular collapse or death. He also points out that there is no documented trend that suggests an increase in severe anaphylactic reaction to any particular manufacturer of vaccines.
With the tremendous number of vaccines on the market several questions need to be asked before vaccinating. (1) Is the dog at risk of significant exposure to the disease the vaccine is designed to prevent? (2) Does the vaccine have a history of causing adverse reactions in this age/breed of dog? (3) Does the dog have a history suggestive of prior allergic reactions to vaccinations? If so, should the dog be treated with antihistamines and/or corticosteroids immediately after vaccination?
While we have to assume that the benefits of vaccinations when given in accordance with current recommendations far outweigh the risk of vaccine-induced illness/disease, recent reports have raised concerns over the relationship between vaccination and possible immune-mediated disease in dogs.
One of the most significant scientific advances in the last century has been the ability to isolate and transfer specific sequences of DNA (genes) from one organism and recombine them with the DNA of another. This is recombinant technology and it holds much promise for diagnostics, pharmacology and vaccinations.
Several new vaccines are products of recombinant technology. Recombinant vaccines surpass conventional vaccines by providing a targeted immune response with “unprecedented safety” and they do it without having to injection killed or modified-live organisms. Recombinant vaccines do not have adjuvant added. Adjuvants are chemicals used to enhance the immune response to a weak immunizing agent. These chemicals are aluminum hydroxide, aluminum phosphate and calcium phosphate. Many oncologists and internists feel the absence of adjuvants is important in reducing the risk of vaccine-induced adverse reactions. Adjuvants are implicated in injection-site granuloma and fibrosarcoma in cats.
Recombinant vaccines are the vaccines of the future. Veterinary clinicians will be able to create a focused immune response and will no longer have to inject whole organisms nor numerous associated antigens. The future of recombinant technology is promising and it is reasonable to foresee the development of vaccines for conditions never thought possible to vaccinate against, such as fungus causing disease, parasites and potentially cancer.
Richard B. Ford, DMV, MS, Diplomate ACVIM, Diplomate (Hon) ACVPM is a Professor of Medicine at North Carolina State University, College of Veterinary Medicine in Raleigh, NC.
Ford, Richard B: “Vaccines and Vaccinations: The Road Ahead”
Back to Health Resources