Necessary Vaccinations for Your Cat


Bryan Huynh

- Updated February 19, 2024

Necessary Vaccinations for Your Cat

Vaccines and pet insurance are an essential part of protecting your cats from catching dangerous and potentially fatal diseases and helping them live a long, healthy, happy life.

What To Know About Vaccines For Cats

Vaccines protect against bacteria, infectious microorganisms, and viruses by preparing the body to recognize these as threats and kickstart the immune system.

When the body is faced with a disease after inoculation, it will be able to either prevent or lessen the severity and duration of the infection.

Even if your cat is vaccinated and shows no symptoms, they can still have the microorganisms in their body and spread it to other non-vaccinated cats in the household.

Vaccines are important for the longevity and overall health of your cat or kitten. In many states, vaccines are required by local and state law, due to the fact that some diseases pose threats to other animals and humans.

Vaccines are tested by government regulatory bodies with strict guidelines to ensure that it is safe and effective for your cat.

There are many factors that come into play when it comes time to administer a vaccine, including age, lifestyle, overall wellbeing, and outside factors and risks. You can even opt for a single injection (called a monovalent vaccine) that protects against multiple common infections as opposed to multiple vaccines (which your cat will definitely prefer). Talk to your vet to determine the best vaccine protocols for your cat. Keep in mind that vaccinations will take up to a few weeks to go into effect and they may not always offer complete immunity, so be sure to keep your cat safe from dangerous environments and infected animals.

It's important to keep vaccinations up-to-date, even if your cat is an indoor-only cat -- there is still a risk they could slip outside or come into contact with bacteria or viruses at a kennel or playdate. However, indoor cats most likely do not need as many vaccinations as their outdoor counterparts.

There are three main types of vaccines:

  • Modified live vaccines: These vaccines contain genetically modified or weakened organisms that won't cause infection but replicate and help build immunity; these vaccines aren't ideal for immuno-compromised or pregnant cats.
  • Inactivated vaccines: These vaccines use organisms (genetically modified or otherwise) that have been killed and may have an added ingredient called an adjuvant; while they don't give as much protection as live vaccines, they can still make the immune response stronger.
  • Subunit (recombinant DNA) vaccines: These are vaccines in which an infectious organism has been broken and only has parts of it included.   These can be given intranasally or through an injection, depending on what works best for your cat.

When To Vaccinate Your Cat


Until a certain age, kittens receive antibodies from their mother that protects them from diseases. Vaccinating a cat too early can cause these antibodies to interfere with the effectiveness of the vaccine.

However, kittens can begin receiving vaccinations as early as 6 to 8 weeks of age with boosters being given at 10 to 12 weeks and then again at 14 to 16 weeks.

Adult cats typically only need boosters once every 3 years (depending on how long the vaccine lasts); however, the first booster is typically scheduled one year after their kitten vaccinations are completed. Make sure that you keep a consistent vaccination schedule to best protect them.

To determine which boosters are necessary, veterinarians can test your cat's blood for antibody tithers; low amounts of antibodies means your cat will need a booster. However, you should take into consideration that these tests can be more expensive than a booster and can also be stressful for your cat.

Indoor cats should receive a booster shortly before going to a situation where they will be around other cats (boarding, etc).

The best time to vaccinate your cat is right after you bring them home (if they are old enough). Booking an appointment as soon as you adopt your cat is essential to ensure you and your vet can come up with a wellness and vaccination plan. Most of the time, vaccines are covered by pet insurance.

Types Of Vaccines

There are two types of vaccines administered to cats: core and non-core vaccines.

Core Vaccines

Core vaccines are recommended to all cats, regardless of their lifestyle and environment. These vaccines are recommended by the American Association of Feline Practitioners (AAFP) and include:

  • Feline viral rhinotracheitis, calicivirus, and panleukopenia (FVRCP): Kittens can receive this shot at 6-10 weeks, 11-14 weeks, and then again at 15+ weeks. Adult cats should receive a booster annually after their kitten FVRCP series has ended.   This vaccine (also called the distemper shot) is a combination shot that protects against three diseases:   * Feline viral rhinotracheitis (FVR), also known as herpes virus type 1 (FHV-1), can be caused by both the FVR virus (FHV-1) or the calicivirus (FCV). It's commonly referred to as the feline upper respiratory infection (URI) and sometimes mistakenly referred to as the cat flu. Symptoms of this include sneezing, congestion, conjunctivitis, and discharge. It can even cause oral ulceration and pneumonia in rare cases.   This is a common infection and can cause long-term issues for cats and serious problems for kittens, including a second case of the infection, even if they haven't been exposed to it again. While the vaccine doesn't provide complete or lasting immunity, it can protect your cat from severe and long-lasting cases of FVR.   * Feline caliciviral disease (FCV) has several viral strains that can cause oral ulcerations/gingivitis/stomatitis (painful inflammation of the gums and teeth), symptoms of upper respiratory infections (nasal discharge, sneezing, etc), and -- in rare circumstances -- hair loss, crusting of body parts, hepatitis, and even death.   * Feline panleukopenia (FPL) is also known as feline distemper or feline parvovirus and is caused by the FPL virus or feline parvovirus (FPLV). While it's uncommon now due to widespread vaccination, it is still extremely contagious and carries a high risk for your cat if they contract it; it has a particularly high mortality rate in kittens. The virus kills white blood cells and makes your cat more susceptible to secondary infections.   Infection can result in severe and possibly fatal gastroenteritis (stomach and intestinal infection), along with decreased energy, vomiting, diarrhea, dehydration, depression, and collapse.
  • Rabies: The rabies vaccine is required by law in most states due to the fatality of the disease -- not just for cats, but all mammals, including humans. One bite from an infected animal can cause quick deterioration, neurological issues, and death in only two months.   Cats over 6 months of age should be vaccinated against rabies; make sure you keep the vaccination records after and continue to vaccinate them annually or every three years after (as recommended by your veterinarian).

Non-core Vaccines

Non-core vaccines are vaccines that are given depending on the cat's lifestyle and risks.

For example, when you have an outdoor cat, you need to take extra precautions to protect them. If you plan on letting your kitten venture outside before they are fully vaccinated, make sure they are supervised and stay in less risky areas close to home.

However, depending on the number of cats they may be exposed to (going to a groomer, staying at a kennel, etc) and the known diseases in your area, you might want to consider the following vaccines:

  • Feline leukemia (FeLV): This vaccine prevents cats (especially outdoor cats) from contracting feline leukemia, an incurable disease and serious viral infection that can spread through close contact (grooming, fighting, mating, etc) and bodily fluids (such as milk, saliva, feces, and urine).   Feline leukemia is extremely dangerous: most infected cats will die from immune system damage, lymphoma, anemia, or tumors. However, some cats may go into regression and live a fairly healthy life.   The virus can take months to cause visible symptoms of the disease, so your veterinarian may do a blood test before vaccination. In spite of precautions, it's still possible for cats to become infected.   Depending on where you live, veterinarians may consider this to be a core vaccine. The FeLV vaccine can be given to kittens 11-14 weeks old and the initial shots are two doses given 3-4 weeks apart; boosters are given the following year and every 1-3 years after (depending on risk).
  • Feline chlamydiosis/chlamydial conjunctivitis: This infection is caused by the bacteria Chlamydophila felis and can result in inflammation of the conjunctiva (membrane around the eye), upper respiratory infections, and even infertility.   It can be treated with oral and/or topical antibiotics over the course of a few weeks.   Kittens can be vaccinated at 8-9 weeks of age and receive a second shot 3-4 weeks later. The chlamydia vaccine may also be included in some FVRCP vaccines (known as FVRCP-C).
  • Bordetella: The bordetella bacteria can cause upper respiratory infections; this vaccine is important if your cat will be in a space with lots of animals. It won't prevent the disease, but it can lessen the severity and duration of the illness.
  • Feline infectious peritonitis (FIP): FIP is caused by a coronavirus; being infected by coronavirus is more common than the development of FIP.   Vaccines for FIP are recommended for cats living in higher-risk situations or exposed to other cats (catteries, kennels, etc).
  • Feline immunodeficiency virus (FIV): FIV is transmitted through close contact and is recommended for cats who spend time outdoors.

Side Effects Of Vaccine

Vaccinations are incredibly helpful and beneficial to your cat's health, but every medical treatment comes with some amount of risk.

Adverse reactions to vaccinations are typically mild and usually only affect less than 1% of cats. These side effects include local inflammation, lethargy, loss of appetite, and transient fever, and typically only last 24-48 hours.

More serious side effects include trouble breathing, diarrhea, lameness, hives, or vomiting. Contact your veterinarian immediately if these occur.

In rare cases -- 1 in 10,000 -- anaphylaxis and death may occur.

Sarcomas -- a rare cancerous mass that develops at the vaccine site and grows slowly -- may also occur at the same frequency as anaphylaxis. Be sure to check your pet for any swelling after injection and if swelling becomes larger than 2 centimeters, grows a month after the injection, or lasts longer than 3 months, a biopsy will be necessary. These sarcomas can be treated through surgery if caught early.

It's important to take your cat to regular checkups for both preventative care and treatment. Pet insurance can help cover the costs of vet visits so they can stay healthy, happy, and active through their life. Look to our trusted services here.

What happens if I don't vaccinate my cat?

Without a vaccination, your cat will be at a higher risk of contracting serious and potentially fatal diseases such as rabies, hepatitis, feline leukemia, and FIV.

Will vaccines always work for my cat?

Vaccines can protect most cats but in rare cases, they may not be effective for several reasons, including:

  • Different strains of viruses
  • Kittens have antibodies from their mother that they receive from nursing, which provides immunity until a certain age; these antibodies can sometimes block the effects of a vaccine until they wear off, so a booster shot mmay be necessary
  • Your cat was ill, stressed, or had a weak immune system during the vaccination, which can prevent a positive response to vaccination
  • The vaccine worked and prevented a serious disease but your cat shows mild symptoms

Talk to your veterinarian about any concerns you have regarding vaccine efficiency and the best way to care for your cat.

About The Author

Bryan Huynh

Bryan Huynh

Product Tester & Writer

Bryan Huynh is a dedicated Product Tester & Writer. Just as insurance has your back, Bryan works to review and inform you about the wide range of insurance products available, ranging from business, auto, health, home, pet, to life insurance.

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