Animal vaccination is a perennially timely and controversial subject. The short answer, Jade, is that nobody knows how often pets should receive vaccines. Nobody knows whether pets need vaccines every year (although they probably don’t).
Although titers probably will be widely used in the future, they aren’t common now for two reasons. First, nobody truly knows how to interpret them (that is to say, nobody knows what titer level is protective for each disease). Second, titers measure only half of the immune system (a portion called humoral immunity) and ignore the other half (called cell-mediated immunity).
A very bad experience from the other night reminded me of a stark truth. Although giving too many vaccines may cause health problems for some pets, giving too few vaccines is virtually guaranteed to lead to sick pets.
I was working at an emergency hospital when a family brought a six-month-old Poodle to my office. The Poodle had a 12 hour history of poor appetite, vomiting, and diarrhea. He had never been vaccinated.
A test of his stool revealed that he was infected with parvovirus. Untreated parvovirus is a deadly disease. Parvovirus is preventable with vaccines. If that puppy had been properly vaccinated, he would not have caught the disease.
To make matters worse, the family had another unvaccinated puppy at home. I explained to them that their other puppy would almost certainly catch the disease. And then they revealed that, three months ago, the family had lost a third (unvaccinated) dog to parvo.
This means that, in the course of a single appointment, I became aware of two puppies who needlessly suffered from a preventable disease because of lack of vaccination. A third puppy is almost certain to become ill and possibly die because of the family’s irresponsibility.
Although over-vaccination is not an optimal scenario for pets, please remember that it is better than the other extreme. If you don’t vaccinate your pets at all, you are asking for them to get sick.