Vaccines and Immunity: Part 1 


I’d like to take this perfect opportunity in our current state of Coronvirus vaccination in humans to discuss vaccinations and immunity in cats and dogs. If you own a cat or dog, it’s very likely that without hesitation, your pet received a set of initial vaccines as a puppy or kitten, and then a booster vaccine every year throughout their life. But is this annual protocol necessary?  


Let’s talk about immunity! 


Animals receive antibodies from their mothers while still in the womb. This is called maternal or passive antibodies. Although some variances can occur, such as the health of the mom and what antibodies she naturally possessed, puppies and kittens are born protected from all the diseases the mom had antibodies for. 


For example, a healthy, pregnant female that had proven immunity against Parvovirus, Distemper and Rabies, some of the major diseases deadly diseases we vaccinate our dogs for, will pass on this immunity to her pups while she is pregnant. So, when the puppy is born, it is protected, but for how long? 


We know that it takes the immune system somewhere between 8-24 weeks to fully mature. This is a pretty large variance, and has much to do with genetics as well as environment, where it lives, what it’s exposed to and so much more. 


Ideally, the first vaccination would be given just before the maternal antibodies are completely gone and before exposure to disease. But, when is this? Conventional vaccine protocol was put in place in the late 1970’s to protect our pets and today it is believed by traditional methods to begin vaccinations between 6-8 weeks, again at 12 weeks and then at 16 weeks of age. 


It is also known that giving a vaccination while maternal antibodies are present, the vaccine is blocked and little, if any immunity will develop.  


According to many experts, including Dr. Peter Dobias, DVM, it is believed that the following can occur in an immature immune system: 


a). The vaccine will not trigger the production of antibodies because the immune system is too immature. 

b). The vaccine can destroy the maternal antibodies, thus leaving the pet less protected. 

c).Boosters have proven unnecessary, as most dogs remain protected after only one vaccination. 


According to Dr. Dobias, it is strongly believed that immunity in dogs and cats lasts a lifetime after just one vaccine. Dr. Ronald D. Schultz, Professor and Chair at the School of Veterinary Medicine, University of Wisconsin-Madison, studied immunity in dogs because he believed “little or no research has been done to demonstrate that the practice of annual revaccination has any scientific value in providing greater immunity than would be present if an animal was never revaccinated or was revaccinated at intervals longer than a year” 


He went on to say “furthermore, we have found that annual re-vaccination, with the vaccines that provide longterm immunity, provides no demonstrable benefit and may increase the risk for adverse reactions”. 


I worked as a veterinary assistant in the 1980’s and saw firsthand the havoc and heartbreak that Parvo Virus had on dogs and puppies. I watched hundreds die and it affected and shaped me in a ways I didn’t fully understand until later. If there was ever a person that was pro-vaccine for pets, particularly for Parvo Virus, it was me. I firmly believe we need to understand how the body works and how and when and when not to use vaccines with our pets. 


This article was not written to induce fear of vaccines, nor, to discredit their importance in the role of immunity. In addition, I am not implying that the veterinary community is purposely deceiving us. I know, inherently, that veterinarians absolutely love pets and want only whats best to keep them healthy. But as science unveils how the immune system works and new information develops, it is my hope that the veterinary community begin to consider other methods to keep our pets immune systems healthy. 


In preparing for this writing, it became clear that not only was this likely the most relevant and most important article I’ve written for this column, but that I would not be able to present this topic in just this month’s space. I invite you to continue reading on my website for the full article, or, to look for “Part 2” in the May issue. 


Schultz, R.D. Current and Future Canine and feline vaccination programs. Vet Med 3: No. 3, 233-254, 1998.  

Stronger Immunity and Fewer Vaccines for Puppies and Adult Dogs by Peter Dobias, DVM