The Vaccine Controversies
The Vaccine Controversies
In recent years, there has been much controversy, even amongst veterinarians, about which vaccines to give to our canine and feline companions and how often. Vaccines are medical agents and there are risks associated with both undervaccinating and overvaccinating. How many, which ones, and how often? Answers to these questions will differ for each patient depending on their location, lifestyle, age, and breed. For me, that means educating clients about the issues surrounding vaccines and working with them to make choices that are most appropriate for their circumstances. If you are interested in the evolution of the vaccine controversies, just keep reading. Or, you can skip to the information about commonly recommended vaccines - information that should be helpful in order to make the best choices on behalf of your animal companion.
Vaccines were once welcomed advancements to preventive health care. In the early eighties, for example, canine Parvovirus outbreaks killed puppies by the dozen. As a volunteer at a veterinary hospital in Hawaii, I witnessed wards of puppies with high fevers, intractable vomiting, and bloody diarrhea that just couldn't be stopped. Most of those puppies died. And the disease was so highly contagious that entire litters and kennels would be affected. When first introduced, the canine Parvovirus vaccine was very much welcomed because it gave veterinarians a means of preventing this horrible disease. Soon, all dogs that passed through the veterinarian's door were vaccinated annually, according to label directions.
In order to make preventive health care more efficient, vaccines for different diseases were batched and pets would come in for their "annual shot." Vaccines made some of diseases much less common. In fact, some younger veterinarians have not seen a case of canine Distemper, canine Parvovirus, feline Panleukopenia, or feline Calicivirus. In some parts of the country (not Hawaii), these are thought of as exotic diseases of the past, much like Mumps, Measles, and Rubella in humans.
In the nineties, veterinarians started to take note of vaccine reactions. Not all vaccinated patients had adverse reactions. In fact, it was a relatively small number of the vaccinated population, but some of the reactions were really bad. Malignant tumors at the injection site were particularly disturbing. I had one patient develop a partial paralysis (that fortunately resolved with time). I've witnessed collapse, seizures, hives, facial swelling, vomiting, fever, and generalized aches and pains following vaccination. There is speculation about vaccines prompting autoimmune diseases like immune-mediated hemolytic anemia (IMHA). Given that the goal of veterinary care is to maintain, help, and not harm patients, all adverse reactions are very disturbing.
As growing numbers of veterinarians were reporting adverse reactions to vaccines for diseases they had never seen, the necessity of annual vaccination came into question. After all, we don't vaccinate humans every year for their entire lives. What vaccines should dogs and cats really get? And how often? The truth of the matter is that we really didn't have the data to answer these questions. Hence the controversy - lots of opinions and not enough information to really know.
Scientifically and medically, the length of immunity provided by a vaccination beyond one year was unknown. It is still unknown for many vaccines. Vaccine manufacturers are generally not motivated to prove that their vaccine could actually provide immunity for longer periods of time. After all, annual vaccines are big business. To be fair, vaccines have been the bread and butter for many veterinarians as well. Regardless, in the late nineties, there was a lot of speculation that the vaccines did provide extended immunity, but no proof. And what about variability? Did immunity vary depending on how many prior vaccinations the patient received? What about age? Breed? Immune status or other ailment? The research is happening. Slowly we are learning how long different vaccines provide immunity under different conditions; but it will take many more years before all the details are worked out.
In the meantime, vaccines (like other medical therapy) are most effective and least harmful when used judiciously. Part of responsible veterinary preventive health care is educating clients about the safety and efficacy and risks associated with different vaccines, and then determining a protocol appropriate to the individual patient's risk factors for the diseases and for adverse effects from the vaccine. Both undervaccinating and overvaccinating can potentially be bad for your animal companion.
It can be a lot of information for a veterinarian to communicate and a client to process during an average office visit. Regardless, it is the mission of Kindred Spirit Kindred Care to empower clients to make educated and informed choices on behalf of their animal companions. Hence, my clients are offered the following information about the available vaccines. Then we work together to determine an appropriate protocol for their animal companion(s) based on their location, lifestyle, breed, age, prior vaccines and vaccine response, and health status. Moreover, we reevaluate our protocol as new information becomes available and as their animal companion's circumstances change.
Vaccines are medical agents designed to stimulate an immune response. The goal for a Parvovirus vaccine, for example, is to prompt the production of Parvovirus antibodies, which are like soldiers of the immune system that patrol the body, recognize and eliminate Parvovirus invaders.
There are different ways of designing a vaccine. One way is to administer a weak form of the virus into the patient. This is called a modified live virus (MLV) vaccine and most canine Distemper and Parvovirus vaccines are in this category. The vaccine commonly administered to puppies is a modified live virus and really should not be administered to puppies under 6 weeks of age. In fact, in my opinion, MLV vaccines should be administered cautiously to puppies under 8 weeks of age. Puppy immune systems aren't equipped to do much until the reach a certain developmental stage, usually between 8 and 12 weeks of age. It seems risky to me to inject live viruses, however weak, into a puppy without an immune system that is developed enough to process them.
A second way of stimulating an immune response is to combine a dead virus with an adjuvant. Dead viruses alone generally do not stimulate immunity, so the adjuvants are added to prod the immune system. Adjuvants are proprietary trade secrets, so manufacturers are not required to disclose their exact chemical composition. Adjuvanted vaccines have been implicated in causing very bad tumors at the injection site in a small number of cats. Many of the vaccines commonly administered to kittens and cats, as well as some of the Feline Leukemia vaccines are adjuvanted vaccines.
A third way vaccines are now being designed is through recombinant gene technology. This involves taking DNA segments from the disease-causing virus and splicing it into another "safe" virus thereby genetically engineering a mutant virus that should prompt an immune response but not cause disease.
Beyond that, opinions vary greatly. How frequently you booster "core" vaccines and which of the "non-core" vaccines you chose to have administered to your animal companions will depend on their individual risk for disease. The following information is to help you make informed decisions.
From an animal health perspective, vaccination programs are most effective at preventing and eradicating disease and maintaining a healthy population when there is widespread community participation. When some individuals are vaccinated multiple times and others are not vaccinated at all, the disease will still persist in the community. Moreover, the individuals determined to avoid those diseases may encounter adverse reactions and problems possibly related to overvaccination.
Vaccines are an important part of a preventive health care program, but like all other medical treatments should be administered judiciously according to individual patient risk for the disease, which will depend on their location, lifestyle, age, and sometimes breed. Potential for adverse events should also be considered. Vaccine titers allow us to determine an individual's immunity against certain diseases rather than risk overvaccination.
The ultimate goal is to protect and not to harm our animal companions. Vaccines can aid in disease prevention, but should not be relied upon as the guarantees to good health. Consider integrating other forms of prevention. The most certain way of protecting a cat from FeLV or FIV is to prevent direct contact with other cats. Tick control is the first line of defense against Lyme disease. Similarly, avoidance of Lepto-contaminated water is good preventive practice. With both Lyme and Lepto, awareness of disease symptoms and early detection helps to limit fatalities. Maintaining a high plane of nutrition, overall general health, and a strong immune system will help to protect your animal companion from all ailments, even the many that we don't have vaccines for.
If there is a particular topic that you would like to see discussed, you may email me at sfnakaya@kindredspiritkindredcare.com.
As with any reference, these pages are not a substitute for veterinary care. Veterinary practice is an eyes, ears, nose, and hands-on profession which cannot be accomplished over the Internet.