Vaccinations for kittens and Cats

By Sophie Kininmonth · 4 Dec 2025 (updated 21 Jul 2026) ·6 min read

Vaccination is the single cheapest way to keep a cat out of serious trouble. The diseases it prevents are not exotic: cat flu moves quietly through households and shelters, and panleukopenia can kill a young kitten. Most people arrive with the same three questions, which vaccines a cat actually needs, when the first needles should happen, and how often boosters really matter. This is a practical, Australia focused guide to core and risk based vaccines, the timing behind the kitten series, what "boosters" mean in real life, and the side effects worth watching for. It also covers what to do about a lump at an injection site.^{1, 2, 3}

Why vaccinating matters

Vaccines do not make a cat invincible. They train the immune system so that, if exposure happens, illness is less likely and often less severe. That matters most in kittens, whose immune defences are still learning what normal looks like, and in multi cat settings where viruses move from nose to nose with very little fuss.^{1, 2}

Indoor only cats are not exempt. Panleukopenia virus is hardy in the environment, and cat flu viruses can arrive via a new cat, a boarding stay, a vet visit, or a brief escape outside. Infections travel on shoes, carriers and visiting hands, not just outdoor adventures.^{1, 2}

Core vaccines in Australia (the "F3")

In Australia the routine core vaccination for cats is commonly called F3. It protects against:^{1, 2}

Feline panleukopenia (also called feline enteritis, caused by feline parvovirus)
Feline herpesvirus (FHV-1), one of the main causes of cat flu
Feline calicivirus (FCV), another major cause of cat flu

These are the vaccines most vets recommend for every cat, regardless of lifestyle, because the diseases are widespread and can be serious, especially in young or unvaccinated cats.^{1, 2}

Risk based vaccines (only for some cats)

Some vaccines are best treated as risk based, useful for certain cats and unnecessary for others. Your vet weighs local disease patterns, your cat's habits, and the likelihood of exposure.^{2, 4}

Feline leukaemia virus (FeLV)

FeLV vaccination may be recommended for kittens and young cats, and for cats with meaningful exposure to other cats, especially those with outdoor access or in fostering, shelter or roaming households. The decision should follow a risk and benefit discussion with your vet, and testing is typically recommended before vaccination.^{2, 4}

Feline immunodeficiency virus (FIV)

FIV risk is tied to biting and fighting, so this tends to be a discussion for cats that roam and get into scuffles. One point matters for Australian readers: the WSAVA guidelines do not recommend routine FIV vaccination, and availability varies by country and over time. Your vet can tell you what is currently used locally and what trade offs apply.⁴

Rabies (an Australia specific reality check)

Rabies vaccination is a routine legal and public health requirement for cats in many countries, but the rabies virus is not present in Australia. Australia does have Australian bat lyssavirus, a related virus carried by bats, which is managed by avoiding bat handling and through appropriate human care after exposure. If you are travelling or relocating overseas with your cat, rabies vaccination may become relevant because of the destination's rules.^{5, 6}

When to start: kitten vaccinations

Kittens usually begin core vaccination at 6 to 8 weeks, then continue every 3 to 4 weeks until at least 16 weeks of age. In higher risk settings such as shelters the course may extend to 16 to 20 weeks, because some kittens still have maternal antibodies that block early vaccine doses.^{2, 7}

The series is not busywork. It is a way of catching the moment when maternal antibodies fade and the kitten's own immune system can properly respond.⁴

Typical F3 timing (general guide)

6 to 8 weeks: first F3
10 to 12 weeks: second F3
14 to 16 weeks (or later): final kitten F3 dose

Exact timing can shift depending on your kitten's age at adoption, health status, and local disease risk.^{2, 7}

Adult cats: boosters and how often they are needed

After the kitten course, cats usually need a follow up booster within the next year, which catches any cat that did not mount a strong response during the kitten series. After that, many core vaccines can be given at three yearly or longer intervals for low risk cats, though some cats may still be advised to vaccinate more often based on exposure risk and the vaccine product used.^{2, 8}

If an adult cat has unknown or incomplete vaccination history, guidelines commonly recommend two core vaccine doses 2 to 4 weeks apart, then ongoing boosters based on risk and the vaccine's duration of immunity.²

Before the appointment: simple preparation that helps

Most cats cope better when the day is predictable and calm. A few small choices reduce stress and make it easier for the vet to examine your cat properly.¹

Bring your cat in a secure carrier, with familiar bedding if possible.
Tell the clinic about any past vaccine reactions, long term illnesses, or current medications.
Reschedule if your cat is clearly unwell (vomiting, diarrhoea, fever, lethargy), unless the clinic advises otherwise.

Side effects: what is normal, and what is not

Most vaccine side effects in cats are mild and short lived, such as sleepiness, a quieter appetite, or local tenderness where the needle went in. These typically settle within a day or two.³

More serious reactions are uncommon but important. Facial swelling, breathing difficulty, repeated vomiting, collapse, or profound weakness soon after vaccination should be treated as an emergency and assessed straight away.³

Lumps at the injection site (including the "3-2-1 rule")

Small, temporary lumps can happen after injections. Rarely, a cat can develop an aggressive tumour at an injection site, known as feline injection site sarcoma. Because early action matters, many feline guidelines recommend monitoring any post injection lump using the 3-2-1 rule: investigate a lump that is still present 3 months after injection, is more than 2 cm in diameter, or is growing 1 month after injection.³

Clinics also try to place injections where surgery would be more straightforward if a problem ever developed, often low on a limb rather than between the shoulder blades.³

Cost: what shapes the price in Australia

Vaccination costs vary by clinic and by what is included in the consult. The total usually depends on:

whether it is a kitten series (multiple visits) or an adult booster
whether your cat needs additional risk based vaccines, for example FeLV
any health checks, parasite control, or tests done at the same appointment

If you are comparing clinics, ask whether the price includes the full physical exam (heart, teeth, eyes, weight, temperature) as well as the vaccine itself.

Quick checks: when to call the vet

Any sign of breathing trouble, facial swelling, collapse, or repeated vomiting after vaccination³
A lump that meets the 3-2-1 rule³
Your kitten is behind schedule. Do not restart the course at home, as your vet will design the catch up plan²

References

Sophie Kininmonth

Dog lover and writer at My Pets Australia, sharing practical breed guides and care advice for Australian pet owners.