Cat Vaccination Guide: What Every Cat Owner Should Know

Why vaccines matter

Cats can catch several serious viral and bacterial infections, some without effective treatment. Vaccines teach your cat’s immune system to recognize these pathogens, so it can fight them off when the real thing shows up.

Without vaccination:

• Feline panleukopenia has a very high mortality rate in kittens
• Rabies is 100% fatal once symptoms appear, and can spread to humans
• Feline leukemia virus weakens the immune system over months to years and makes lymphoma much more likely

Core vs non-core vaccines

Veterinary vaccine guidelines divide cat vaccines into two groups:

Core vaccines are recommended for every cat, indoor or outdoor:

• FVRCP (Feline Viral Rhinotracheitis, Calicivirus, Panleukopenia)
• Rabies
• FeLV for kittens under 1 year old

Non-core vaccines depend on how your cat lives:

• FeLV for adult cats that go outdoors or live with cats that are FeLV-positive or untested
• Chlamydia felis, considered only in multi-cat settings where the infection has been confirmed
• Bordetella bronchiseptica, mainly relevant for cats entering shelters, catteries, or boarding facilities

The FIV vaccine has been discontinued in the US and Canada but is still sold in Australia and New Zealand. An FIP vaccine exists, but the major guidelines don’t recommend it because the evidence that it protects is weak.

Understanding each vaccine

FVRCP (the “3-in-1” vaccine)

This combination vaccine protects against three diseases:

In US clinics this is sometimes labeled “feline distemper.” Same vaccine, older name.

Rabies

Rabies is a fatal viral disease of the nervous system, transmissible to humans. Most US states and many countries legally require rabies vaccination for cats, even indoor-only ones. Where a state has no statewide rule, city or county ordinances often set one anyway, so check local law rather than assuming your cat is exempt.

Feline leukemia virus (FeLV)

FeLV spreads through prolonged close contact: mutual grooming, shared bowls, bite wounds. Kittens are far more susceptible than adults, which is why FeLV is considered core for cats under one year old.

Test before you vaccinate. Only FeLV-negative cats are candidates for the vaccine, and age and exposure decide the rest. A cat that is already positive gets nothing from it. The test is fast and cheap, and most clinics run FeLV and FIV together from one blood sample. If the result is positive, here’s what to do after a positive FeLV test.

Kitten vaccination schedule

Kittens get antibodies from their mother’s milk (maternal antibodies). That protection fades over weeks to months, at a different pace in every kitten, so kittens need a series of doses rather than a single shot. For the rest of the first month, see Bringing Home a Kitten.

Kitten vaccination milestones from 6 weeks to 6 months

The final FVRCP dose should be given at 16 weeks or later so maternal antibodies have faded enough for the kitten’s immune system to respond. In shelters, or multi-cat homes that have had panleukopenia, the kitten series continues to 20 weeks. The 6-month booster is there because a few kittens hold on to maternal antibodies longer, and their earlier doses may not have taken.

Adult cat booster schedule

After a complete kitten series, healthy low-risk adults need periodic boosters:

Indoor-only cats with no exposure to other cats may not need FeLV boosters after the first year. Protection against panleukopenia can last 7 years or more, and some clinics offer titer testing, a blood test for antibody levels, to decide whether an adult needs another dose. It’s worth asking.

At the animal hospital in Taipei where I work, the vets recommend an FVRCP booster every year, and many clinics in Taiwan do the same. Both schedules are reasonable. Cats that board, share a home with other cats, or go outdoors lose herpesvirus and calicivirus protection sooner and do better with yearly boosters, and a yearly visit doubles as a checkup. Your vet can match the interval to your cat’s lifestyle.

Adopting an adult with unknown vaccine history

If you adopt an adult cat with no records, the usual catch-up plan is:

• FVRCP: two doses, 2 to 4 weeks apart
• Rabies: one dose (local law sets the frequency from there)
• FeLV: test first, then vaccinate only if negative and at risk

Give both FVRCP doses even if the cat looks healthy. One dose protects less reliably against herpesvirus and calicivirus, and many shelter cats already carry herpesvirus.

What it costs

US clinic prices vary widely. Typical full-service practice ranges in 2025–2026:

Low-cost vaccine clinics and shelter-affiliated programs run shots for $15–$25 each without an exam, which is reasonable for healthy adults but skips the physical that catches early disease.

Injection-site sarcoma (FISS)

Adjuvants are additives in some vaccines that boost the immune response. The trade-off is more inflammation at the injection site. In a small number of cats the inflammation never settles and eventually turns into a malignant tumor, feline injection-site sarcoma (FISS). It’s rare: roughly 1 in 5,000 to 1 in 12,500 vaccinations.

Before the 1990s, vets gave most vaccines between the shoulder blades. Tumors started appearing there, and a sarcoma that close to the spine is nearly impossible to remove cleanly. Vaccines now go low on the legs, sometimes at the tip of the tail, and never between the shoulders. A tumor on a leg can be removed completely by amputation, with a far better outlook than one beside the spine.

Which vaccine goes where

Each vaccine has its own site, so if a tumor ever appears, the vet can tell which one caused it:

What if my vet used the scruff? Don’t panic. FISS is rare, and the vaccine has done its job. Over the next few months, feel the spot now and then, and if you find a lump, check it against the 3-2-1 rule. Next time, ask for the shot in a leg.

Non-adjuvanted vaccines

The inflammation adjuvants cause is thought to be linked to FISS, though other injections can trigger it too. Non-adjuvanted vaccines get an immune response a different way. In the US, non-adjuvanted rabies vaccines come in 1-year and 3-year versions. The 3-year one is given once, boosted a year later, and then every 3 years.

Non-adjuvanted rabies costs more (often $36–$70+ for the 3-year vs $25–$50 for adjuvanted). When both are available, non-adjuvanted is the preferred choice, but an adjuvanted vaccine given in the right spot on the leg is still a safe one.

The 3-2-1 rule for monitoring

A small lump where the shot went is normal for a few days and usually goes away within 2 to 4 weeks. Go back to the clinic if:

• The lump is still there 3 months after the shot
• It’s larger than 2 cm
• It’s still growing 1 month after vaccination

That’s the 3-2-1 rule. A lump that meets any one of these should be biopsied early, not watched indefinitely. Caught early, FISS can be removed with wide, clean margins. Once it’s large, that gets much harder.

Post-vaccination care

Most cats have no reaction at all. When they do, it’s usually mild and gone within 24 to 48 hours:

• Slight lethargy
• Reduced appetite
• Mild fever
• A small lump where the shot went

Allergic reactions after the shot

Most severe allergic reactions (Type I hypersensitivity) happen quickly, typically within the first 30 to 60 minutes after vaccination. But reactions can also be delayed by several hours, so keep watching for the rest of the day. Signs to watch for:

• Vomiting or diarrhea
• Facial or eyelid swelling
• Hives, especially around the muzzle
• Difficulty breathing, wheezing
• Collapse, weakness

Any of these signs means a vet visit the same day. Facial swelling, breathing trouble or collapse can’t wait at all. Call the clinic on your way so they can get ready.

If your cat has reacted to a vaccine before, tell the clinic before the shot. Depending on how bad the last reaction was, the vet may keep your cat for observation afterwards or give an antihistamine first.

Can senior cats stop getting vaccines?

There’s no age limit for vaccines, and most healthy seniors stay on the usual schedule. If your senior cat fits all of these, it’s worth asking about an antibody test first:

• 11 years or older
• Indoor-only, with no contact with other cats
• Finished the kitten series and adult boosters
• Has a chronic illness such as kidney disease or hyperthyroidism

If the blood test shows panleukopenia antibodies are still high enough, your cat can skip a dose. Rabies has nothing to do with age and still follows local law.

Tracking vaccines in Furwise

Kittens get a dose every few weeks, adults once every year or three, and with gaps that long it’s easy to forget when the last one was. With several cats, each is on its own timeline. In Furwise you log each cat’s past vaccines and when the next one is due, and it reminds you as the date gets close. Family members can see the same record.

Frequently Asked Questions

Do indoor cats need vaccines? Yes. Core vaccines (FVRCP and rabies) are recommended for every cat, indoor-only included. Panleukopenia virus survives on surfaces and can be tracked into the home on shoes or clothing. Rabies vaccination is also legally required in many areas regardless of lifestyle.

How often do adult cats need booster shots? Low-risk adults can get FVRCP every 3 years, sometimes longer after an antibody test. Cats that board, live with other cats or go outdoors do better with yearly boosters. Rabies follows local law and the product, typically every 1 or 3 years. FeLV is every 2 to 3 years, and only for cats that go outdoors or live with FeLV-positive or untested cats.

How much do cat vaccinations cost in the US? Expect $25 to $50 per shot at a full-service clinic, plus a $50 to $100 office or exam fee per visit. Non-adjuvanted rabies runs $36 to $70 or more. Low-cost vaccine clinics offer $15 to $25 per shot without an exam, which is fine for healthy adults but skips the physical.

What if my cat missed a booster? Missing by a few weeks or even months usually doesn’t mean restarting. For FVRCP, if your cat is more than a year overdue, your vet may give two doses 2 to 4 weeks apart to be safe. Rabies depends on the gap and your state’s law. Some states require restarting if it has lapsed.

My cat had a reaction last time, can we still vaccinate? Often yes, with some changes. Tell the clinic about the last reaction before the shot. The vet may give an antihistamine first, switch to a non-adjuvanted product, split vaccines across separate visits, or keep your cat for 30 to 60 minutes afterwards. After a severe reaction, the vet sometimes keeps only the legally required rabies shot and pauses the rest.

Is the FIV vaccine still available? Not in the US or Canada, where it has been discontinued. It’s still sold in Australia and New Zealand. FIV spreads mainly through bite wounds, so without a vaccine the focus is testing and keeping cats from fighting.

What is the difference between adjuvanted and non-adjuvanted vaccines? Adjuvants are additives that boost the immune response, but they cause more inflammation where the shot goes in, which is thought to be linked to FISS. Non-adjuvanted vaccines get an immune response another way, with less inflammation (though the risk isn’t zero). They cost more.