Vaccine research from the November 15th Journal of the American Veterinary Medical Association confirms what I wrote about here. Small dogs are more likely to suffer adverse reactions to vaccines than larger dogs. The current study gives more specifics. It turns out dogs who weigh less than 10 lbs are 7 times more likely to have an adverse reaction to a vaccine than dogs who weigh more than 100 lbs.
This finding should not surprise anyone since the dose of vaccine is the same for every dog. How can the same dose be appropriate for a ½ lb Chihuahua as for a 150 lb Great Dane? In fact this study calls for the vaccine industry to develop lower dose vaccines for small dogs. But don’t hold your breath.
I vaccinated my own dog, Katy, with half the dose of the Distemper/Parvo vaccine when she was 12 weeks old. I’ve been doing yearly blood titers ever since. Twelve years later she still has protective immunity. I’m not saying it works that way for every dog but there is that potential.
This study also found that certain larger breeds of dog are also more likely to have a vaccine reaction. These include the German Shorthaired Pointer, Mastiff, and Pit Bull Terrier. Apparently there is a genetic predisposition to vaccine reactions in these breeds.
A new finding from this study is that the Leptospira vaccine (AKA Lepto) doubles the chances for an adverse reaction. Whether the Lepto vaccine is given alone or as part of the Distemper/Parvo vaccine, dogs receiving it are 2 times more likely to have a problem.
Although the chances of any dog having an adverse reaction to a vaccine is very low (less than 1 in 100), it does not make sense to give more vaccines than are needed. Every vaccine you give your pet increases the chance of a reaction. I recommend having yearly blood titers done after the initial series of puppy vaccines. I have written more about vaccines and titers here and here.
Have any of your pets ever had an adverse reaction to a vaccine?