Published by: Ingrid King. Last Updated on: July 14, 2023 by Crystal Uys

Veterinarian doctors analyzing blood samples of cat in laboratory under microscope

There is no question that vaccines protect against disease – but they also present considerable risk. Sadly, far too many cats are still being over-vaccinated because too many veterinarians, and cat guardians, still think annual “shots” are necessary.

Vaccine side effects

Vaccines are implicated in triggering various immune-mediated and other chronic disorders (vaccinosis). Vaccines are also implicated in the high incidence of vaccine-induced sarcomas in cats. The incidence of these tumors ranges from 1 in 1000 to 1 in 10,000 cats. They can develop as quickly as 4 weeks or as late as 10 years post vaccination.

Vaccine recommendations from major veterinary organizations

The American Association of Feline Practitioners (AAFP) recently updates its vaccine guidelines. The new guidelines are even more conservative than those issued in previous years, but the frequency of vaccination may still exceed what your cat actually needs to remain protected against disease.

Most of the AAFP recommendations are for vaccinations to be given every three years. However, studies conducted at the University of Wisconsin School of Veterinary Medicine have shown that immunity for some vaccines last seven years or longer, which suggests that even the more conservative vaccine protocols recommended by major veterinary organizations are still too frequent.

What is titer testing?

Titer testing may be a safer alternative to ensure that your cat is protected without introducing unnecessary vaccines. A titer test is a blood test that measures the presence and level of antibodies for a particular infectious agent in the cat’s blood. These antibodies reflect the combination of potential natural exposure and vaccination. Antibodies are created when the immune system responds to the antigens in the body.

The presence of a measurable antibody titer indicates that the cat is protected from disease. Studies show that 90% % to 98% of cats that have been properly vaccinated develop good measurable antibody titers to the infectious agent being measured. Titers do not distinguish between immunity generated by vaccination and by exposure to the disease.

The next time you take your cat to your veterinarian for her annual or bi-annual check up, discuss titer testing as an alternative to vaccinations.

Cat blood tests
Image Credit: PRESSLAB, Shutterstock

This article was previously published on and is republished with permission.

Featured Image Credit: Kzenon, Shutterstock

About the author