Vaccinate or Not? The Pros and Cons of Vaccinating Your Indoor Cat


Even though indoor cats aren’t exposed to the outdoors, routine vaccinations are still essential for them. Vaccines protect cats against several highly contagious and potentially fatal feline diseases. According to *Nevins Veterinary Corner*, some of the most common and dangerous diseases that feline vaccines guard against include:

  • Panleukopenia (feline distemper) – A severe and highly contagious viral disease.
  • Calicivirus – A common virus that causes respiratory illness and oral ulcers.
  • Herpesvirus – Another viral cause of upper respiratory infection.
  • Rabies – A fatal viral disease that can be transmitted to humans.
  • Feline leukemia virus (FeLV) – A retrovirus that weakens the immune system.

While the risk of exposure may be lower for indoor cats, unvaccinated felines remain susceptible to these potentially fatal diseases. Kittens and cats that go outdoors are especially vulnerable. However, even exclusively indoor cats can pick up diseases from other pets, people, or stray animals that enter the home. Therefore, core vaccines are recommended for nearly all cats, regardless of lifestyle.

Core Vaccines

There are two core vaccines that are recommended for all cats according to the American Animal Hospital Association (AAHA) and the American Association of Feline Practitioners (AAFP).

The first is the FVRCP vaccine which protects against three common feline viruses: feline viral rhinotracheitis (FVR), calicivirus (FCV), and panleukopenia (FPV). This combination vaccine is considered a core vaccine because these highly contagious viruses can cause severe illness in cats. FVR can lead to upper respiratory infection, FCV causes oral/respiratory disease, and FPV causes severe gastrointestinal disease. The FVRCP vaccine is extremely effective at preventing cats from contracting these viruses. It is given as a series of shots to kittens starting as early as 6 weeks old, with boosters every 3-4 weeks until 16 weeks old. Adult cats need a FVRCP booster shot every 1-3 years, depending on risk, to maintain immunity.

The other core vaccine is rabies. Rabies is a fatal viral disease that can spread between animals and people through saliva. The rabies vaccine is vital to protect cats against this deadly virus. Depending on local laws, rabies vaccination may be mandated for all cats. The initial rabies vaccine is typically given around 12-16 weeks old, followed by a booster in 1 year, then boosters every 1-3 years. The rabies vaccine protects cats for 3 years according to federal guidelines, although some states still require annual boosters. Rabies vaccines are highly effective when given properly.

Non-core Vaccines

These include vaccines that are considered optional based on your cat’s risk factors and lifestyle. Here are some of the main non-core vaccines for cats:

Feline leukemia (FeLV) – This virus compromises the immune system and increases risk for other diseases. According to the AAHA Guidelines, the FeLV vaccine is recommended for cats at risk of exposure through activities like hunting, living with infected cats, or time outdoors. Kittens can be vaccinated as early as 8 weeks and receive boosters 3-4 weeks later.

Feline immunodeficiency virus (FIV) – Similar to HIV in humans, FIV attacks the immune system. FIV vaccines may be advised for free-roaming cats at risk of exposure through wounds from fighting.

Chlamydia – Caused by Chlamydia felis bacteria, this disease affects the eyes and respiratory tract. The vaccine may benefit cats entering shelters or breeding colonies.

Bordetella – This bacterial respiratory infection causes kennel cough. The intranasal vaccine is an option for cats living with dogs or going into boarding.

Vaccine Schedule

The core vaccines, including FHV-1, FCV, FPV, rabies, and FeLV (for cats under 1 year old), have a recommended vaccination schedule per the 2020 AAHA/AAFP Feline Vaccination Guidelines (Feline Vaccination Table). Kittens should receive a series of vaccinations starting at 6-8 weeks old, with boosters every 2-4 weeks until 16-20 weeks old. After the kitten series, cats should receive a booster 1 year later and then every 3 years for core vaccines.

For the non-core vaccines, the schedule will depend on risk factors. For example, the FeLV vaccine is recommended yearly for outdoor cats while indoor cats only require an initial dose. Other non-core vaccines like FIV and FIP are only recommended for high-risk cats. It’s important to consult with a veterinarian to determine which non-core vaccines may be recommended based on the cat’s lifestyle and risks.

In summary, the core vaccine schedule has standardized recommendations, while the non-core schedule should be tailored to each cat’s individual needs. Following the recommended schedules ensures cats maintain strong immunity against the most common and deadly feline diseases.

Risks of Not Vaccinating

Not vaccinating an indoor cat comes with significant risks. Some of the most dangerous diseases that cats should be vaccinated against include:

Panleukopenia: Also known as feline distemper, panleukopenia is a severe and often fatal disease caused by the feline parvovirus. It attacks the gastrointestinal tract, bone marrow, and central nervous system. Kittens are especially susceptible. According to Cornell University, mortality rates for kittens exposed to panleukopenia can reach 90%[1].

Rabies: Rabies is nearly 100% fatal in domestic cats once symptoms appear. The viral disease affects the central nervous system, causing neurological symptoms and aggression. Cats are usually infected through exposure from an infected animal bite. Though less common in cats than dogs, rabies vaccination is core for cats in most jurisdictions[2].

By not vaccinating against these dangerous diseases, cat owners put their pets at significant risk of severe illness and death. Indoor cats can still be exposed through other animals, people, or objects brought inside the home.

Potential Vaccine Reactions

As is the case with any vaccine, cats may experience adverse reactions in response to vaccination. The most common side effects are mild and transient in nature. According to the American Animal Hospital Association, adverse vaccine reactions occur at a rate of about 0.52% of vaccinated cats.

Typical reactions include:

  • Local swelling, tenderness, or pain at the injection site
  • Lethargy and decreased appetite
  • Mild fever

These vaccine reactions generally resolve within a few days. To help relieve discomfort, you can apply a warm compress to the injection site and monitor your cat’s temperature and appetite. Contact your veterinarian if symptoms persist beyond 48 hours.

Very rarely, a cat may experience a severe allergic reaction known as anaphylaxis. This occurs within minutes of vaccination and can be life-threatening if left untreated. Symptoms include facial swelling, hives, vomiting, diarrhea, difficulty breathing, and collapse. If you observe these signs, seek emergency veterinary care immediately.

While concerning, severe vaccine reactions are extremely uncommon in cats. The benefits of core vaccines far outweigh the small risk. Still, it’s important to be aware of potential side effects and monitor your cat closely after each vaccination.


Certain medical conditions may warrant exemption from some routine vaccines. According to the AVMA (American Veterinary Medical Association), rabies vaccination exemptions may be considered for dogs and cats with a documented medical contraindication. However, exempting pets from rabies vaccination is extremely rare. Exemptions require certification from a licensed veterinarian, and pets with waived rabies vaccination must be confined to avoid potential rabies exposure and lengthy quarantines. For example, see the AVMA’s policy on rabies vaccination waivers:


The cost of vaccinating an indoor cat can vary depending on the specific vaccines given. According to Latimes, core vaccines like rabies, rhinotracheitis, calicivirus, and panleukopenia usually cost $15-$45 per vaccine. The initial kitten series of core vaccines costs $100-$200 in the first year. After that, annual booster shots of the core vaccines run about $80-$150 per year, according to Rover.

Non-core vaccines like feline leukemia, Chlamydia, and FIP cost more, ranging from $25-$60 per vaccine. So a full set of non-core vaccines could add $100 or more to the total cost. Indoor cats generally only need the core vaccines, unless specifically recommended by a vet for health reasons.

Many low-cost vaccination clinics and shelters offer discounted rates for core vaccines, which can help reduce costs. But annual booster shots are still recommended to maintain immunity.


When it comes to vaccinating indoor cats, the evidence strongly supports doing so. While indoor cats are at lower risk of exposure to infectious diseases than outdoor cats, the risks are still present. By vaccinating an indoor cat, you protect them from extremely dangerous diseases like rabies, feline leukemia virus, and feline panleukopenia virus.

Some of the key takeaways include:

  • Core vaccines like rabies, FPV, and FHV-1 are critical for all cats, including indoor cats.
  • Non-core vaccines can provide additional protection from diseases like FIV and FeLV based on your cat’s individual risk factors.
  • Kittens need a series of vaccines on a set schedule to ensure full immunity.
  • While vaccine reactions can occur, they are typically mild. The risks of not vaccinating are far greater.
  • Exemptions from vaccination should only be granted when truly medically warranted.

By staying up to date on your indoor cat’s vaccines, you are protecting their health and wellbeing. Do not wait until it’s too late. Consult with your veterinarian to develop the optimal vaccine schedule for your feline companion.


The content in this article did not cite any specific external sources. However, the recommendations and information provided are based on general veterinary guidelines and scientific consensus on indoor cat vaccination protocols. The content aimed to synthesize recommendations from leading veterinary associations like the American Association of Feline Practitioners (AAFP) and draw on established veterinary research into the risks and benefits of core and non-core feline vaccines.

To learn more about current scientific research and veterinary perspectives on indoor cat vaccinations, please refer to the following evidence-based resources:

These leading veterinary resources help support the recommendations made in this article and provide more in-depth information on current scientific research into feline vaccinations.

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