“We should aim to vaccinate every animal, and to vaccinate each individual less frequently”
This is the conclusion reached recently by the vaccination guidelines group (VGG) of the World Small Animal Veterinary Association. The VGG strongly recommends that all dogs and cats receive the benefit of vaccination, protecting the individual and also providing “herd immunity” that minimizes the likelihood of outbreak of infectious disease.
The VGG has defined core vaccines that should be given to all dogs to protect against severe, life threatening diseases and non-core vaccines which should only be used in specific individuals at particular risk. The core vaccines protect against canine distemper virus, canine adenovirus and parvovirus. Three puppy vaccinations are advised to be followed by the first booster vaccination, 12 months later. It is probable that these modified live virus vaccines provide a good duration of immunity and need only be given every three years.
In the UK, vaccination against leptospirosis (which causes liver/kidney disease and is transmitted via rat urine) is also considered core. Unfortunately, the duration of immunity following vaccination against bacterial diseases is often low and in this case is likely to be less than 12 months. A popular non-core vaccine which has similar duration is that used against kennel cough, which in addition may not always be fully protective but reduces the severity of disease. This would be most commonly used for dogs that regularly attend boarding kennels, shows or other meets.
Veterinary surgeons are advised to make decisions upon the frequency of core vaccinations and whether additional non-core vaccinations are necessary based on a risk-benefit assessment for their individual patients and using knowledge of the prevalence of various infectious diseases in their area (unfortunately, such information is rarely available on a countrywide, let alone local, basis and tends to be somewhat anecdotal).
Most UK vets, with the aforementioned in mind, have adopted a basic approach of advising that adult dogs (after completing puppy vaccination and first booster) are boosted against distemper, parvo and adenoviruses every three years and annually against leptospirosis.
The puppy vaccination guidelines from the VGG differ somewhat from the most common currently used UK protocols in that three initial vaccinations are advised with the third given at 14-16 weeks of age. The aim is to provide optimal immunity and is perhaps more important if uptake of core vaccinations is reduced due to concerns about over vaccination. Less than 30% of UK dogs are vaccinated which is very much below the levels necessary to confer “herd immunity”.
In future, I think it is likely that serological testing will play a more important role when making decisions about individual pet vaccination. It should soon be possible for your vet to take a blood test and determine in their practice lab the degree of immunity that your pet has to certain diseases. First we need to be sure that these are validated and accurate and hopefully not too expensive for routine use.
On a more personal note, I have no hesitation in vaccinating my own deerhounds according to current guidelines and feel that the benefits of protecting them from serious, sometimes fatal, diseases far outweighs the very small risk of adverse effects.
ALYSON RICHARDSON BVSc Cert VD MRCVS
