VACCINE PROTOCOL FAQ

Arnold Plotnick DVM, ACVIM, ABVP
General Practice & Preventative Medicine

QUESTION

What vaccine protocol do you recommend for indoor only cats? How do you or would you vaccine your own cat in this situation?

ANSWER

All cats should be tested for FeLV and FIV. If negative for both viruses, cats should then be evaluated in regard to vaccine requirements. Kittens and cats should be vaccinated against the two upper respiratory viruses, herpes and calici, as well as against panleukopenia. Kittens and cats should also be vaccinated against rabies. One year later, revaccination against all four of these viruses should be performed. I recommend using a rabies vaccine that confers immunity for 3 years. I rarely, if ever, recommend vaccination against Bordetella, chlamydia, Giardia, Microsporum canis, or FIP.

If the cat is to be completely indoors, with no possibility of encountering a cat of unknown leukemia status, I do not vaccinate against FeLV.

As for future vaccinations, you now have two options. Let's say that the cat was vaccinated against herpes, calici, and panleukopenia at year zero (kitten), and year one. The cat now returns for evaluation at age two. You can perform titers against these viruses, and if any titer comes back negative, revaccinate. Or you can skip titers and revaccination altogether and rely on the current evidence that immunity to these viruses after vaccination lasts a minimum of three years, and often much longer. The same holds for year three: run titers and vaccinate if titers indicate, or skip the titers and assume that the cat is protected.

At year four, it gets a bit trickier. You should definitely vaccinate against rabies, as the rabies vaccine was a three-year vaccine. As for herpes, calici, and panleukopenia, you can run titers, or you can simply revaccinate, since it has been three years since the last FVRCP vaccination. The advantage of running titers annually is that you might find that vaccination is not needed, allowing you to skip the vaccine. The disadvantage is that titers, at the moment, are fairly costly.

A recent study has shown that the presence of antibodies against either of these viruses indicates immunity to the disease. Cats who do not have antibodies against these viruses may or may not be immune to disease upon challenge with the offending virus. Some cats develop protective antibodies immediately upon challenge via memory cells, while others contract the illness upon challenge. As such, vaccinating a cat with a negative titer might not be necessary; however, using titers as your determining factor would still result in the cat receiving fewer vaccinations over his lifetime than if an arbitrary time frame, such as one year or three years, was chosen.

If the goal is to reduce the number of vaccinations administered to an indoor cat, running titers every year seems to be the way to go. However, skipping the titers and vaccinating every three years is certainly reasonable, as it significantly reduces the number of vaccines given compared to annual revaccination, and the FVRCP vaccine is less likely to result in vaccine induced sarcomas, compared with rabies and leukemia.