Current Veterinary TherapyChapter XI

Canine and Feline Vaccines

Authors - Tom R. Phillips and Ronald D. Shultz

CANINE AND FELINE VACCINES

ANNUAL VACCINATIONS

A practice that was started many years ago and that lacks scientific validity or verification is annual revaccinations. Almost without exception there is no immunologic requirement for annual revaccination. Immunity to viruses persists for years or for the life of the animal. Successful vaccination to most bacterial pathogens produces an immunologic memory that remains for years, allowing an animal to develop a protective anamnestic (secondary) response when exposed to virulent organisms. Only the immune response to toxins requires boosters (e.g., tetanus toxin booster, in humans, is recommended once every 7 to 10 years), and no toxin vaccines are currently used for dogs or cats. Furthermore, revaccination with most viral vaccines fails to stimulate an anamnestic (secondary) response as a result of interference by existing antibody (similar to maternal antibody interference). The practice of annual vaccination in our opinion should be considered of questionable efficacy unless it is used as a mechanism to provide an annual physical examination or is required by law (ie. certain states require annual revaccination for rabies).