Published by: Ingrid King. Last Updated on: February 9, 2023 by Crystal Uys

Little cat at the veterinary - getting a vaccine

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.

The American Association of Feline Practitioners (AAFP) recently updated its vaccination guidelines. The guidelines divide vaccines into core and non-core vaccines, and recommended that vaccination protocols should be tailored to the individual cat’s health and lifestyle.

Core vaccines

Core vaccines are those recommended for all cats. The feline panleukopenia
(FPV), feline herpesvirus-1 (FHV-1), and feline calicivirus (FCV) vaccines fall into this category. These vaccines are most commonly administered in a combination FVRCP vaccine.

Non-core vaccines

Administration of non-core vaccines should be determined based on an individual assessment of the cat’s lifestyle and exposure risk. The AAFP considers rabies, feline leukemia virus (FeLV),
Feline immunodeficiency virus (FIV), Chlamydophila felis, Bordetella bronchiseptica, feline infectious peritonitis (FIP) and dermatophyte vaccines non-core.

Rabies vaccines are required by many jurisdictions. While some rabies vaccines are only required every three years, the only non-adjuvanted rabies vaccine currently on the market is labeled for one year. Most feline veterinarians recommend this vaccine as a safer option to the three-year-vaccines, even though more frequent vaccination will be required.

Frequency of vaccines

Many factors play into how frequently cats should be vaccinated. There is no one-size-fits all approach, and it is imperative that cat guardians work with a veterinarian who practices individualized feline medicine. The cat’s health, age, lifestyle, and risk of exposure will all determine which vaccines the cat should get, and how frequently these vaccines should be boostered.

Why do kittens need a series of vaccines?

For the first few weeks of their lives, kittens ingest antibodies contained in their mother’s milk. These antibodies help protect the kitten from infectious diseases until its own immune system is more mature. Unfortunately, thse maternal antibody also interfere with a vaccine’s ability to stimulate the kitten’s immune system. To counteract this problem, veterinarians often administer a series of vaccines, usually beginning when the kitten is around six to eight weeks of age. Vaccination is then repeated at three- or four-week intervals. In some cases, the initial vaccine is not given until maternal antibodies have disappeared altogether.
Risk of vaccinations
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.

Although rare, vaccines can also cause serious allergic reactions. These reactions will typically occur within minutes to hours following vaccination. Symptoms can range from vomiting, lethargy, and diarrhea to anaphylactic shock.

Vaccine titers as an alternative to vaccination

Titer testing for a particular infectious agent measures the presence and level of antibodies in the blood. The presence of a measurable serum antibody titer indicates protection from disease. Discuss titer testing with your cat’s veterinarian as a viable alternative to vaccination.
If your cat is still receiving “annual shots,” discuss individualized vaccination protocols with your veterinarian, or find one who practices individualized feline medicine.

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

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