My staff was crazy busy the other day with a bunch of sick, geriatric patients, and someone was heard saying "We need puppies and kittens!" Personally, I happen to love working with seniors, but sometimes, I have to admit it's nice to hug a little tiny creature just starting its journey on a long and (hopefully) healthy life.
I get questions almost daily about getting the youngsters started out on the right paw, so to speak. For the first decade I was in practice, I followed the old, traditional vaccination protocols. Core vaccines were started at 6 weeks of age and repeated every two to three weeks until the pet reached 16 weeks. This sometimes resulted in a series of 4 to 5 vaccinations. Now I cringe when I think of all those poor animals with stressed immune systems.
The current research on pet vaccination has dramatically changed the way we vaccinate youngsters. The immunity the puppy or kitten receives through the placenta and the mother's first milk (colostrum) will remain strong for six to twenty weeks and will gradually diminish. Every individual is different and the timing for maternal immunity drop-off varies. This is why there is so much confusion over when vaccinations will work best for puppies and kittens.
In the past, it was believed that giving more vaccinations meant there would never be a period where the pup or kitten was unprotected. However, research has shown that more vaccinations does not mean better immunity; in fact, over-vaccination can cause a less vigorous immune response against disease and increases the risk of adverse reactions to vaccines. Antibodies from a previously administered vaccine will block the formation of more antibodies when another vaccine is given. One study showed that at 12 weeks of age, 95% of puppies will be able to respond to a vaccination.
When a vaccine is given, the immune system reacts to make antibodies against the altered virus in the vaccine. The immune response works very hard for a few weeks to mount this defense. Booster vaccines, if given, should never be given two weeks apart. If a booster is desired, you should wait at least 3 to 4 weeks or more.
The immune system does not completely mature until 6 months of age; any vaccine given after 6 months of age will provide a better response.
My current recommendations are to make sure the mother cat or dog has a positive titer prior to breeding to make sure she will pass antibodies to the offspring through the colostrum. A vaccination for core diseases (distemper and parvo) can be given to the puppy or kitten between 12 and 16 weeks of age, with a follow-up titer 3 to 4 weeks after vaccination. If a titer cannot be performed, give a second vaccination 4 weeks after the first. I wait until 6 months of age to give rabies vaccinations.
I do not recommend vaccinating for Lyme, Leptospirosis, or Kennel Cough for most of my patients, but will look at these on an individual basis, depending on lifestyle.