Risk factors associated with vaccine adverse reactions JAVMA

I’ve been caring for many animals for a long, long time now. And as a result, I’ve watched all kinds of changes take place in veterinary medicine. In my early teens, a neighbor paid me to walk her dog over to the vet for a checkup and “shots.” The vet looked the dog over carefully, pronounced the 8 year old female to be in great shape, and was about to send me on my way when I reminded, “She also needs her shots.” I wasn’t totally clear what that meant, but I knew it was important. The vet smiled, and said at her age, this dog did not need any further shots other than rabies, and sent me on my way.

Somehow, that morphed into yearly shots regardless of age, and sometimes, depending on the vet, lots of them. I lived through the early parvo years, where dogs sometimes died very fast in horrible ways. I was a trainer then, and had a great vet I worked with. He was forward thinking and very experienced. When I panicked, dreading the thought that my dog might also end up in a bloody, awful death, he urged me to use the cat vaccine (feline panleukopenia) – no parvo vaccine was available. Though off label, it worked and kept many dogs alive before a canine parvo vaccine could be developed. (https://pubmed.ncbi.nlm.nih.gov/6299140/)

That dog went on to be the foundation dog for my entire breeding program, and his descendants are laying here at my feet. I was also able to convince many clients to discuss the cat vaccine option with their vets, and they did. Not one of my clients’ dogs died of parvo.

Pure luck? Possibly. But the point is this: there is a place for vaccines. I am far from vaccine happy, and use core vaccines as per Dr Schulz, keeping an eye always to what might become endemic in my area and put my animals at risk.

Vaccines are not without risk. Hell, life is not without risks. But being informed on what those risks are, and who might be more at risk is critical. I am not interested in arguing pro or cons of vaccines here. I’ve lived through 2 litters with parvo (the early 1980s were NOT fun) and all puppies lived to tell the tale. I’ve pulled a dog through sub-acute distemper which could have been avoided, and am old enough to remember dogs in the neighborhood dying of distemper, an awful death.

There’s more (because I’m old now) but the point is this: be informed, be aware, know what your individual dog or breed risk may be. Also know that for your veterinarians, few things are as heartbreaking as having to treat – and maybe lose – an animal for something that was preventable.

Walking the line between doing the least while also providing support and (hopefully) optimal protection is the trick. And no one has all the answers.

Again, no big arguments pro or con vaccines here, please. This is often as big a hot button item as feeding or training! Just absorb the information, and add it to your understanding.

From https://avmajournals.avma.org/view/journals/javma/aop/javma.23.03.0181/javma.23.03.0181.xml?ref=barkandwhiskers.com



To evaluate patient and vaccine factors associated with adverse events (AEs) recorded within 3 days of vaccine administration in a large cohort of dogs.


4,654,187 dogs vaccinated in 16,087,455 office visits in a 5-year period at 1,119 hospitals of a corporate practice.


Electronic medical records of dogs vaccinated between January 1, 2016, and December 31, 2020, were searched for diagnoses of possible AEs recorded within 3 days of administration of vaccines without concurrent injectable heartworm preventative. Patient risk factors (age, sex, breed, and weight) and number and type of vaccine were extracted from records. ORs (and 95% CIs) for risk factors were estimated via multivariable logistic regression mixed models with patient as a random effect.


AEs were recorded following 31,197 vaccination visits (0.19%, or 19.4/10,000 visits). Reported AE rates increased from 1 to 4 vaccines administered and among individual vaccines were greatest for rabies vaccine. AE rate was generally inversely related to body weight, with largest rates in dogs ≤ 5 kg. The largest AE rates were noted in French Bulldogs and Dachshunds (ORs > 4 compared to mixed-breed dogs).


Risk factor information can be used to update vaccination protocols and client communication. Breed differences may indicate genetics as the primary risk factor for adverse vaccine reactions following vaccinations.