Kitten Vaccination Schedule: The Basic Milestones

Vaccination is the simplest and most effective way to protect kittens from dangerous infectious diseases. A kitten does not get one shot and finish; it needs a series of vaccinations over its first few months. This article walks you through the common age milestones so you can talk confidently with your veterinarian.

Why kittens need several vaccinations

At birth, kittens receive antibodies from their mother's first milk (colostrum). These antibodies fade over the first few months, but the timing varies from kitten to kitten. While maternal antibodies are still high, a vaccine may not work fully.

Because no one knows exactly when maternal antibodies wear off, veterinarians usually give repeat vaccinations a few weeks apart. That way, at least one vaccination lands at the right time for the kitten's own immune system to respond. Stopping partway through may leave a kitten unprotected even though it has had some shots.

Diseases commonly vaccinated against

Common veterinary guidelines divide cat vaccines into two groups.

Core vaccines, recommended for most cats

• Feline panleukopenia (also known as feline distemper): highly contagious, with a high death rate in kittens, and the virus survives a long time in the environment.
• Feline viral rhinotracheitis caused by herpesvirus: causes sneezing, nasal discharge and eye inflammation.
• Calicivirus disease: causes upper respiratory infection and ulcers in the mouth and on the tongue.
• Rabies: transmissible to people and almost always fatal once symptoms appear. In many places, rabies vaccination is required by law.

The first three are usually combined in a single combination vaccine.

Non-core vaccines, depending on circumstances

One example is the vaccine against feline leukemia virus. Your veterinarian will weigh this based on your cat's lifestyle: whether it goes outdoors and whether it lives with many other cats. Many guidelines recommend vaccinating kittens because their future lifestyle is hard to predict. Testing is usually needed before vaccination.

Typical age milestones

Below are the age milestones from common guidelines. The exact schedule for your cat is decided by your veterinarian, based on age, health, background and the disease situation where you live.

1. Around 6 to 8 weeks old: the first combination vaccine.
2. Boosters every 3 to 4 weeks: further combination vaccines until the kitten is about 16 weeks old or a little older.
3. Rabies: usually given from around 12 to 16 weeks old, depending on local rules and your veterinarian's advice.
4. Booster after the initial series: usually at around 6 months to 1 year of age.
5. Adult cats: regular boosters. How often depends on the vaccine type; your veterinarian will advise.

If you adopt an older cat with an unknown vaccination history, don't worry. Your veterinarian will set up a suitable schedule, often starting with two vaccinations a few weeks apart.

Before and after each vaccination

• Health check first: a cat should only be vaccinated when healthy. If your kitten has a fever, diarrhea or is off its food, tell your veterinarian so the appointment can be postponed.
• Deworming: kittens are usually dewormed regularly. Use the product and timing your veterinarian recommends, read the product label carefully, and never give a dog product to a cat.
• Keep a vaccination record: note each vaccination date and the next appointment. Bring the record to every visit.
• Limit contact: until the series is complete, keep your kitten indoors and away from unfamiliar cats. Wash your hands after touching other cats.
• After vaccination: your kitten may be tired, eat less, run a slight fever or have a sore injection site for one to two days. These are usually mild reactions that pass on their own. Let your kitten rest somewhere quiet with food and water.

Stay at the clinic or watch your kitten closely for a short while after the vaccination. Severe allergic reactions are rare but usually happen early.

Remember to gently feel the injection site over the following weeks. If a small lump appears that does not go away, or grows, tell your veterinarian so it can be checked.

When to see a vet

Contact your veterinarian or the nearest veterinary clinic right away if, after vaccination, your cat has:

• Facial swelling, swelling around the eyes, hives or intense itching.
• Repeated vomiting, diarrhea, difficulty breathing or rapid breathing.
• Collapse, extreme lethargy, pale gums or inability to stand.
• Tiredness and loss of appetite lasting more than two days.
• A lump at the injection site that is still there after a few weeks or is getting bigger.

Apart from vaccine reactions, a kitten that is not fully vaccinated and shows vomiting, diarrhea, refusal to nurse or eat, fever, or eye and nose discharge also needs to see a vet promptly, because illness in kittens can progress very quickly.