W. Jean Dodds, DVM and Ronald D. Schultz, PhD
There is little doubt that application of modern vaccine technology has permitted us to protect companion animals effectively against serious infectious diseases. Today, we can question conventional vaccine regimens and adopt effective and safe alternatives primarily because the risk of disease has been significantly reduced by the widespread use of vaccination programs, which convey underlying population or herd immunity.
For many veterinary practitioners canine vaccination programs have been “practice management tools” rather than medical procedures. Thus, it is not surprising that attempts to change the vaccines and vaccination programs based on scientific information have created significant controversy. A “more is better” philosophy still prevails with regard to pet vaccines.
Annual vaccination has been and remains the single most important reason why most pet owners bring their pets for an annual or more often “wellness visit.” Another reason for the reluctance to change current vaccination programs is many practitioners really don’t understand the principles of vaccinal immunity. Clearly, the accumulated evidence indicates that vaccination protocols should no longer be considered as a “one size fits all” program.
A Purdue University vet school study (by Moore et al), published in 2005 in the AVMA Journal and widely-cited elsewhere (see AAHA Guidelines p. 22), tracked vaccine reactions occurring within 72 hours of vaccination for 1.2 million dogs vaccinated at 360 veterinary hospitals. It showed that small breed dogs receiving multiple vaccines per office visit were at greatest risk of a vaccine reaction. The report recommends: These factors should be considered in risk assessment and risk communication with clients regarding vaccination.
“The VAAE [reaction] rate decreased significantly as body weight increased. Risk was 27% to 38% greater for neutered versus sexually intact dogs and 35% to 64% greater for dogs approximately 1 to 3 years old versus 2 to 9 months old. The risk of a VAAE significantly increased as the number of vaccine doses administered per office visit increased; each additional vaccine significantly increased risk of an adverse event by 27% in dogs ≤ 10 kg (22 lb) and 12% in dogs > 10 kg.” Read more »