Bringing a new cat home means navigating a vet visit fairly quickly — and with it, a conversation about vaccines. The terminology can be confusing: core vaccines, non-core vaccines, boosters, titers. This guide cuts through it and tells you what you actually need to know.
Core Vaccines: What Every Cat Needs
Core vaccines are recommended for all cats regardless of lifestyle, because the diseases they prevent are either highly contagious, severe, or both. There are three:
FVRCP (the "distemper shot")
Despite the name, this protects against three distinct feline diseases: feline viral rhinotracheitis (a herpesvirus causing respiratory infection), calicivirus (another respiratory/oral disease), and panleukopenia (a parvovirus that's highly fatal in kittens). FVRCP is typically given as a series during kittenhood and then boosted every 1–3 years in adults depending on your vet's protocol and your cat's lifestyle.
Rabies
Required by law in most US states regardless of whether your cat is indoor-only. Rabies is fatal and transmissible to humans. Kittens typically receive their first rabies vaccine around 12–16 weeks old, with a booster at 1 year and then every 1–3 years after that, depending on the vaccine formulation.
Non-Core Vaccines: Lifestyle-Dependent
Non-core vaccines are recommended based on your cat's individual risk factors. Your vet will ask about your cat's living situation before recommending these.
FeLV (Feline Leukemia Virus)
Recommended for cats who go outdoors or live with other cats whose FeLV status is unknown. FeLV is transmitted through saliva, nasal secretions, and prolonged close contact. It suppresses the immune system and leads to a range of serious diseases. Indoor-only cats with no contact with other cats carry minimal risk and often skip this vaccine.
FIV (Feline Immunodeficiency Virus)
There is currently no USDA-approved FIV vaccine available in the US (the previous version was discontinued). If your vet mentions it, ask for clarification — an FIV vaccine isn't currently an option in standard US veterinary practice.
Bordetella and Chlamydophila
Occasionally recommended for cats in multi-cat households or catteries where respiratory infections spread easily. Rarely needed for a typical single-cat household.
Kitten Vaccination Schedule
Kittens are born with some maternal immunity, but it wanes. The standard schedule starts the process of building their own immune response:
- 6–8 weeks: First FVRCP
- 10–12 weeks: Second FVRCP; FeLV if recommended
- 14–16 weeks: Third FVRCP; Rabies; FeLV booster if started
- 1 year later: FVRCP and Rabies boosters
- Adult maintenance: Every 1–3 years depending on vaccine and lifestyle
If you adopt an adult cat with unknown vaccine history, your vet will typically restart the series rather than assume prior coverage.
Vaccine Reactions: What's Normal and What Isn't
Mild lethargy and soreness at the injection site for 24–48 hours are normal. So is a small firm lump at the site that resolves within a few weeks — this is the body's local immune response. What to watch for and report immediately: vomiting, facial swelling, difficulty breathing, collapse, or a lump that grows rather than shrinks after 4–8 weeks. The last one specifically — a persistent or growing mass — should always be evaluated, because a rare form of sarcoma can occur at injection sites in cats.
Indoor-Only Cats: Do They Still Need Vaccines?
Yes, with some nuance. Rabies is legally required in most states even for indoor cats. FVRCP is still recommended because the diseases it covers can be carried on clothing and shoes, and because your cat may at some point end up at a vet clinic, boarding facility, or in an emergency situation with other animals. The risk is lower for indoor cats, but not zero. Discuss the specific schedule with your vet — some will extend the interval between boosters for low-risk indoor cats.