January’s vaccination reminders are now landing on the mats of clients whose pet I vaccinated this time last year. Just as you thought the list of jobs has ended another one arrives! They roll round quickly these vaccinations so it’s worth understanding why we do them.
Immunity is the body’s ability to fight off viruses and bacteria, it can be achieved in one of three ways; Via transfer of antibodies through mother’s milk (maternally derived immunity), following infection by a wild type pathogen and recovery from the consequent clinical signs (Disease) or via exposure to a killed or inactivated pathogen without suffering clinical signs (Vaccination). The aim of immunisation is to balance maternally derived immunity (MDI) and vaccination in order to prevent disease.
People often ask why animals have to be vaccinated with greater frequency than humans and it is probably true that vaccines have been licensed with too short a vaccination interval in the past. Vaccines against some diseases are now licensed for use every 3 years and many vets will use these.
One fairly prosaic reason for decreased vaccination interval is simply that animals don’t live as long as humans, so an annual vaccination against leptospirosis (in dogs) is roughly analogous to a 10 year vaccination interval against tetanus (in humans).
Another conflicting factor is that humans are vaccinated on a population basis i.e. what is the maximum vaccination interval that will protect, say, 95% of the population and represent the best value. Pets are vaccinated on an individual basis i.e. what is the maximum vaccination interval that will guarantee immunity in this specific animal, this leads to generally shorter vaccination intervals.
Humans are coming into contact with thousands or tens of thousands of people every year and constantly topping up their immunity to lots of diseases. Pets usually come into contact with only tens or maybe a hundred other animals each year and so exposure to an actively infected animal can overwhelm their immune system.
Without doubt the biggest value from a yearly check up is the physical exam. Pets can’t tell us how they feel so when they’re unwell it’s really helpful to have a baseline physical exam from earlier that year on which to compare. There is also the human aspect of trust which is built up over years of seeing your vet for nice reasons rather than meeting your vet for the first time when your pet needs treatment. So I know you’ve probably got a million other things on your list to do but this is one of the ones that’s worth ticking off.
Mr Richard Harper BVetMed MSc(Onc) MRCVS
T: 0208 4449006 E: firstname.lastname@example.org