Programs supporting regular feline vaccination have contributed both to the health of cats and to public health.
Currently, there are geographically defined core vaccines and individually chosen non-core vaccine recommendations for cats. A number of controversies surrounding adverse reactions to vaccines have resulted in authorities revising their guidelines for feline vaccination.
Recommended administration of vaccines 
In 2006 and 2010, revised guidelines addressed concerns about adverse vaccine reactions by altering the recommended frequency, type, methods, and locations for administration of core and non-core cat vaccines.
General schedule 
Most vaccination protocols recommend a series of vaccines for kittens, with vaccine boosters given at one year of age. Frequency of vaccination thereafter varies depending on the lifestyle of the individual cat, including:
- indoor vs. outdoor
- travel plans
- kennel/boarding plans
- underlying disease conditions
- other exposure risks,
- the disease and vaccine type being considered.
Because these factors may change over time, many professional organizations recommend routine annual examinations, where a vaccination plan for each individual feline can be decided during a discussion between the veterinarian and cat owner.
In their 2010 recommendations, WSAVA (World Small Animal Veterinary Association) emphasized the importance of administering non-adjuvanted vaccines whenever possible, as vaccines that included these immune-stimulating agents were shown to increase adverse vaccine reactions in pets.
WSAVA also prefers serological testing over unnecessary boosters or re-vaccination doses of core vaccines after the initial 12-month booster that follows the kitten series of modified live virus [MLV] vaccines. This is because core vaccines show an excellent correlation between the presence of antibody and protective immunity to a disease, and have a long DOI (Duration of Immunity). Antibody tests can be used to demonstrate the DOI after vaccination with core vaccines, though not for non-core vaccines.
Most vaccines are given by subcutaneous (under the skin) or intramuscular (into the muscle) injection. Respiratory tract disease vaccination may be given intra-nasally (in the nose) in some cases.
Many recent protocols indicate that vaccines should be given in specific areas in order to: ease identification of which vaccine caused an adverse reaction, and ease removal of any vaccine-associated sarcoma.
In North America, vets adopted the practice of injecting specific limbs as far from the body as possible, for example the rear right for rabies, rear left for leukemia, and others in the right front shoulder - being careful to avoid the midline or interscapular space.
This set of locations was not widely adopted outside of North American, and WSAVA's international group made new recommendations that vaccines be administered:
- in subcutaneous (and not intramuscular) sites
- in the skin of the lateral thorax or abdomen (for easier excision of any FISS that occur)
- so as to avoid the interscapular or intercostal regions (as more extensive surgical resection would be needed for sarcomas)
- in a different site on each occasion (either with general locations per species per year or diagrams of where administered on specific visit)
Core vaccines 
Core vaccines are defined as those vaccines which ALL cats, regardless of circumstances, should receive. Core vaccines protect animals from severe, life-threatening diseases which have global distribution.
Rabies (disputed) 
The latest (2006) North American recommendation still includes rabies in the core vaccines. Likewise, the National Association of State Public Health Veterinarians (NASPHV) in the U.S. gives detailed instructions on how to deal with what they describe as a serious public health problem, and includes a useful table, summarizing all the rabies vaccines sold in the U.S.
However, the 2010 international WSAVA recommendation generally considers the rabies vaccine a non-core vaccine, except in areas where the disease is endemic or where required by law.
FVR or FHV-1/FCV/FPV 
In many locations, the rabies vaccine is accompanied by a single combined FVRCP vaccine shot which protects against Feline viral rhinotracheitis, calicivirus, and panleukopenia.
- Feline viral rhinotracheitis (FVR) is an upper respiratory infection of cats, also known as feline influenza, caused by feline herpesvirus 1 (FHV-1). FVR is very contagious and can cause severe disease, including death from pneumonia in young kittens.
- Feline calicivirus (FCV), in addition to FHV-1, is the other common viral cause of respiratory infection in cats.
- Feline panleukopenia virus (FPV), more commonly known as feline distemper, is caused by the feline parvovirus, a close relative of canine parvovirus. It is not related to canine distemper. Panleukopenia is highly contagious and can be fatal.
Non-core vaccines 
Non-core vaccines are those that are required by only those animals whose geographical location, local environment or lifestyle places them at risk of contracting specific infections.
- Except in areas where the disease is endemic or where required by law, the VGG considers the rabies vaccine as non-core.
- Chlamydophila felis: sometimes used as part of a control regime for cats in multiple-cats environments where infections associated with clinical disease have been confirmed.
- Feline leukemia virus (FeLV) is a retrovirus transmitted between infected cats when the transfer of saliva or nasal secretions is involved, for example when sharing a feeding dish. If not defeated by the animal's immune system, the virus can be lethal. The disease is a virus, not a cancer. The name stems from the fact that the first disease associated with the virus was a form of leukemia. By the time it was discovered that the virus was not the same as leukemia, the misnomer had already found its way into the vocabulary of pet owners. If administered, it should be injected in tip of the left rear paw (unless combined with rabies).
- Feline immunodeficiency virus (FIV), commonly known as Feline AIDS is a lentivirus that affects domesticated housecats worldwide. FeLV and FIV are in the same biological family, and are sometimes mistaken for one another. However, the viruses differ in many ways. Although many of the diseases caused by FeLV and FIV are similar, the specific ways in which they are caused also differs. However, a vaccine against this disease is not available in all countries.
- For cats expected to board, be shown, or to enter a kennel situation within 6 months, vets may recommend administering Bordetella, which protects again a respiratory illness commonly known as "kennel cough." However, studies have not shown this product to reduce severity of the feline respiratory disease complex.
Not recommended vaccines 
The following vaccines are not recommended due either to lack of evidence of effectiveness or to a high chance of adverse reaction.
- Feline infectious peritonitis (FIP) is a fatal, incurable disease caused by Feline Infectious Peritonitis Virus (FIPV), which is a mutation of Feline Enteric Coronavirus (FECV/FeCoV). The mutated virus can invade and grow in certain white blood cells, namely macrophages. The immune system's response causes an intense inflammatory reaction in the containing tissues. This disease is generally fatal. However its incidence rate is roughly 1 in 5000 for households with one or two cats.
- Giardia lamblia
In recent years, vaccination has become a controversial topic among veterinarians and pet owners. Studies citing specific adverse reactions and general consequences for long-term health and immunity are both causing professional bodies to recommend reduced frequency in feline vaccination.
In 2010, the American Veterinary Medical Association (AVMA) and American Association of Feline Practitioners (AAFP) developed vaccination guidelines recommending that FVRCP vaccinations generally be administered every 3 years, after completion of the kitten series of shots (which is needed due to maternal antibody interference).
Internationally, the 2010 The World Small Animal Veterinary Association (WSAVA) vaccination guidelines reduce the number of vaccines which should be considered core for felines, as well as recommending less frequent vaccine administration.
However, in an open letter to WSAVA, an Australian pet owner and long-time consumer advocate has created a detailed critique of these guidelines, with numerous scholarly citations, arguing that the 3-year booster or re-vaccination recommendations are either arbitrary or influenced by vaccine manufacturers. She cites the scientific findings of both WSAVA's and other leading researchers, which indicate that, similar to humans, the duration of immunity (DOI) for cats vaccinated early in life with MLV (modified live viruses) is many years, if not the entirety of adulthood, despite the common practice of "boosting" vaccines every 1 to 3 years.
In the executive summary section, the WSAVA guidelines do argue against needless vaccination and in support of "the development and use of simple in-practice tests for determination of seroconversion (antibody) following vaccination." In addition, they also note that "Vaccines should not be given needlessly. Core vaccines should not be given any more frequently than every three years after the 12 month booster injection following the puppy/kitten series, because the duration of immunity (DOI) is many years and may be up to the lifetime of the pet." The open letter critique focuses on the less-nuanced summary of these recommendations in the Tables given for vaccination guidelines, which could imply that re-vaccination should occur every 3 years.
Adverse reactions 
Vets and owners should also consider factors that have been shown to increase the risk of adverse vaccine reactions. Examples of such factors include:
- number of vaccinations per office visit,
- type or ingredients of vaccine itself,
- neutered status,
- general health of the cat,
- and past vaccination history.
See also 
- "The 2006 American Association of Feline Practitioners Feline Vaccine Advisory Panel Report". American Association of Feline Practitioners. Retrieved 2012-06-24.
- "Summary Table: Vaccination in General Practice". The 2006 American Association of Feline Practitioners Feline Vaccine Advisory Panel Report. Retrieved 2012-06-24.
- Vaccination Guidelines Group (VGG) of the World Small Animal Veterinary Association (WSAVA) (2010). "WSAVA guidelines for the vaccination of dogs and cats". Retrieved 2012-06-24.
- "Canine and Feline Vaccination Guidelines". UC Davis Veterinary Medical Teaching Hospital. November 2009. Retrieved 2012-08-26.
- "Feline Life Stage Guidelines". American Association of Feline Practicitioners & American Animal Hospital Association. 2010. Retrieved 2012-08-26.
- Eigner, Diane R. "Feline Vaccine Guidelines". The Winn Feline Foundation. Retrieved 2006-08-27.
- "VAFSTF Vaccine Site Recommendations". Vaccine-Associated Feline Sarcoma Task Force of the American Association of Feline Practitioners (AAFP), American Animal Hospital Association (AAHA), American Veterinary Medical Association (AVMA), and Veterinary Cancer Society (VCS). Retrieved 2012-06-23.
- "Compendium of Animal Rabies Prevention and Control, 2011". Morbidity and mortality weekly report of the Centers for Disease Control. National Association of State Public Health Veterinarians, Inc. (NASPHV). 2011. Retrieved 2012-06-24.
- Feline Infectious Peritonitis (FIP)
- ASPCA: Pet Care: Cat Care: Feline Infectious Peritonitis
- "What should the revaccination (booster) schedule be?". UC Davis Koret Shelter Medicine Program. Retrieved 12 February 2010.
- "Critique of the WSAVA VGG Vaccination Guidelines for Owners & Breeders of Dogs and Cats". 2012-02-06. Retrieved August 26, 2012.
- "Adverse events after vaccine administration in cats: 2,560 cases (2002-2005).". J Am Vet Med Assoc. 2007 Jul 1;231(1):94-100. Retrieved 2012-06-24.
- Vaccination Guidelines Group (VGG) of the World Small Animal Veterinary Association (WSAVA) (2010). "Vaccination guidelines for the owners and breeders of dogs and cats". Retrieved 2012-06-24.
- Horzinek, MC (2010). "Vaccination protocols for companion animals: the veterinarian's perspective". Journal of Comparative Pathology. 142 Suppl 1: S129–32. doi:10.1016/j.jcpa.2009.11.001. PMID 19954796. Retrieved 2012-08-26.
- Common Cat Diseases
- AVMA Principles of Vaccination
- The Vexing Vaccine Issue from JAVMA News
- Feline Vaccines: Benefits and Risks Vaccine-Associated Feline Sarcoma Task Force
- Cat Vaccinations and Health Care Schedule
- Latest vaccine protocols - Felipedia