Antibody titers are blood tests that measure the amount of antibodies in the blood. Following exposure to a disease-causing organism (such as a virus) or a vaccine, the body generates antibodies that help to destroy the organism and prevent or minimize illness if the body is exposed to the same organism again.

Antibody titers do not replace vaccination programs, but in some instances may help your veterinarian determine if your pet has a reasonable expectation of protection against disease. However, there are only a limited number of disease-causing organisms for which antibody titers can suggest your pet’s level of protection, and those antibody tests have limitations. Consequently, a higher antibody titer does not necessarily mean your pet will be protected if exposed to the disease, and a lower titer may not mean your pet’s protection is lacking.