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The 4 Important Core Vaccines Your Indoor Cat Requires

Cats require protection for preventable diseases. You might think that your indoor cat has a pretty low risk of contracting serious disease, but there are some situations that may warrant it. In fact, many vaccines are the law.

The truth is that cat owners in the United States are required by law to ensure their cats have at least the core vaccinations. In fact, the law requires that cats over the age of 6 months be vaccinated against rabies.

Not sure what you should do?

For starters, you’ll need to contact a veterinarian to discuss a vaccination schedule. Your cat will need to get a series of injections at specific times.

We’ll talk more about what those core vaccines are, what they protect against, and how an indoor cat could possibly contract serious illness.

What Does a Vaccine Do?

A vaccine for a cat is a biological preparation that improves immunity to disease.

The practice uses weakened or killed forms of the microorganism, toxins or one of its surface proteins.

The administered vaccines protect cats from infection by stimulating immunity in the kitty’s body without causing illness.

Cat vaccinations have significantly reduced the number of diseases we see today and has helped prevent outbreaks in our local communities.

They are given in a series of dosages at specific intervals from an early age (once they lose their maternal immunity) to protect them against infectious diseases.

Two Types of Cat Vaccines

There are two types of cat vaccines: core and non-core for cat healthcare.

Core vaccines provide protection against the most common diseases that indoor cats face, including:

  • feline leukemia
  • rabies
  • feline herpes virus
  • feline calicivirus.

They are recommended based on risk factors associated with exposure, the severity of disease, transmissibility to humans (zoonotic potential) and effectiveness of vaccination.

Non-core vaccinations protects against less common but potentially deadly illnesses such as feline immunodeficiency virus (FIV) or feline distemper.

Depending on the cat’s lifestyle, specific risks such as indoor or outdoor living, hunting, and exposure to other animals.

cat vaccination

What Health Risks Do Indoor Cats Face?

Indoor cats are at greater risk of getting diseases because they don’t have the same access to outside resources that outdoor cats do.

Outdoor cats can come in contact with animals that have rabies or parasites, which reduces their risk of getting these diseases. But the indoor ones don’t have this advantage and stay inside all day, every day.

Therefore, you must vaccinate your indoor cat regularly to reduce their risk of getting these diseases.

4 Core Vaccines Your Indoor Cat Requires

The following are core vaccines as recommended by the American Association of Feline Practitioners for optimal health. We take a look closely at each one.

1. Rabies Vaccine

Rabies is a fatal disease caused by the rabies virus, which attacks the central nervous system.

The initial transmission occurs when an infected animal bites or scratches another living creature, such as humans and other animals, including your cat.

Rabies vaccinations can prevent infection with this dangerous disease transmitted through saliva entering a wound (even one created by scratching) or human infected with rabies.

The vaccine is given as a series of two or three injections, depending on your cat’s age and should be boosted every one to three years.

Rabies is a deadly disease that can infect any warm-blooded animal, including cats. There is no cure.

It is mandatory in most states for all cats to get vaccinated against rabies, and it is the best way to protect your cat from this deadly virus. It is highly effective in preventing infection and has a very high success rate.

Symptoms of Rabies in Cats

Symptoms of the disease include aggression (such as biting), paralysis in one or both hind legs and drooling due to weakness in the muscles that control swallowing.

These symptoms usually develop within two to six weeks after exposure, and death typically follows shortly after that.

Rabies causes permanent brain damage or death in infected animals. With the vaccine, this is a preventable condition, and all cats should be vaccinated against it.

It is also one of the safest vaccines available, with only mild after effects occasionally seen.

There are three rabies vaccines licensed for use in the U.S. They all have different after effects, which is why your veterinarian might choose one over another for your cat. The two most common of any rabies vaccine are fever and lethargy.

Some cats also develop a sore at the injection site. Your veterinarian can prescribe pain medication or anti-inflammatory drugs to help relieve these symptoms if needed.

2. The FVRCP Vaccine

The FVRCP vaccine protects your cat from feline viral rhinotracheitis (FVR), calicivirus and panleukopenia.

The vaccine, commonly referred to as a distemper shot, is administered to protect your kitty against three highly viral infections, contagious and life-threatening feline diseases.

a. Feline viral rhinotracheitis (FVR)

This is a highly contagious respiratory disease that can cause severe inflammation of the nasal passages and throat. It is caused by a herpes virus and is very difficult to treat.

Up to 90% of unvaccinated cats exposed to FVR will become infected, and about half of them will die from the disease.

This disease can cause sneezing, loss of appetite and lethargy in your cat. It can also lead to pneumonia if it’s not treated promptly with antibiotics and supportive care (fluids) for dehydration caused by vomiting or diarrhea; which often accompanies this disease.

FVR is highly contagious between cats, so keep them separated until all symptoms have cleared up completely for at least two weeks. Bacterial infection caused by FVR can also lead to cat flu.

b. Calicivirus

This is a prevalent virus that can cause severe respiratory illness, fever, loss of appetite and conjunctivitis. It is one of the most common causes of death in kittens. Up to 80% of cats exposed to calicivirus will become infected, and about half of them will die from the disease.

This virus is transmitted through contact with saliva, nasal secretions or feces from an infected cat. It can also be spread through contaminated food or water bowls, bedding or litter boxes. Signs that your cat may have calicivirus include fever, coughing, sneezing, discharge from the eyes and nose, loss of appetite and weight loss.

If your cat has calicivirus, do not allow them to come into close contact with other cats and keep them isolated until they have fully recovered.

c. Panleukopenia

Another highly contagious and deadly viral disease that affects cats of all ages. The condition causes damage to the gastrointestinal tract, nervous system, and bone marrow.

It can lead to severe dehydration due to vomiting and diarrhea. The incubation period for panleukopenia is a few days up to two weeks; it may take another week or more before your cat starts showing signs of illness.

The most common signs of panleukopenia include loss of appetite, lethargy (or depression), fever, vomiting, diarrhea and dehydration, which are all symptoms that you should seek veterinary care immediately if seen in your cat.

It is transmitted through direct contact with an infected animal’s feces or urine and through fleas that carry the virus from one place to another on their bodies without becoming sick themselves.

FVRCP immunizations start at six weeks of age as a series of two or three injections, and booster shots are given every one to three years.

The most common side effects from the FVRCP vaccine include fever, lethargy, anorexia and vomiting.

Less commonly, cats may experience swelling at the injection site, diarrhea or hives. If your cat experiences any of these symptoms after getting vaccinated, contact your veterinarian immediately.

Symptoms of the disease include fever, vomiting, diarrhea and dehydration. Up to 90% of unvaccinated cats exposed to panleukopenia will become infected, and up to half of them will die from the disease.

The FVRCP vaccine provides protection against these three life-threatening diseases, and it is therefore essential for your cat to receive this vaccine regularly.

Before You Move On!

We thought you might be interested in these posts. Check them out after you’ve finished this post.

5 Ways to Get German Shepherds and Cats Behaving Like Family

11 Side Effects of the Rabies Vaccine for Puppies

11 Clinical Reasons to Get the Bordetella Vaccine for Dogs

3. Feline Leukemia vaccine

Feline leukemia virus (FeLV) is a retrovirus that can weaken your cat’s immune system, making them more susceptible to infections and other diseases.

Cats infected with FeLV may experience fever, weight loss or appetite changes.

The virus can also cause anemia (low red blood cell counts), enlargement of the lymph nodes, and enlarged spleen due to the suppression of bone marrow activity.

It is transmitted through saliva, blood or urine from an infected cat. It can also be spread through contaminated food and water bowls, bedding or litter boxes.

The disease has no cure and is often fatal. The best way to protect your cat is through vaccination.

In the Initial vaccinations series, FeLV are started at three months of age as a series of two injections given a month apart then boosted every one to three years.

The FeLV vaccine is an integral part of your cat’s overall health, and it is recommended that all cats be vaccinated against this deadly virus. It’s a core vaccine for cats not older than 16 weeks.

The FeLV vaccine is highly effective in preventing the disease. Studies have shown that vaccinated cats have a 90% chance of not contracting the virus and an almost 100% chance of survival if they become infected.

The FeLV vaccine is very safe and only causes mild side effects in some cats. Most cats do not react to the vaccination, but if your cat experiences a fever or other symptoms after getting vaccinated, contact your veterinarian immediately.

4. Feline herpes virus

Feline herpes virus type I (FHV, FHV-I) is a common virus in cats that causes upper respiratory infections such as colds.

It can also lead to conjunctivitis or inflammation of the cornea, resulting in blindness if left untreated. Feline herpes virus is particularly dangerous for kittens because the immune system has not yet developed enough antibodies to fight off infection from this virus.

The virus is spread through contact with saliva, mucus or blood from an infected cat. It can also be spread through the air, making it easy for other cats to become infected even if they don’t come into direct contact with the sick cat.

The most common symptoms of FHV-I include sneezing, runny nose, eye discharge, fever and loss of appetite. In severe cases, the virus can cause pneumonia which can be fatal. The virus doesn’t survive long outside the cat’s body, so it is not quickly spread to other animals or people.

All cats need to be vaccinated against feline herpes virus, especially kittens that are most at risk for developing severe health complications if infected. Contact your veterinarian today to schedule an appointment for your cat to receive the FHV vaccine.

core vaccines for cats


Vaccines for cats should be given according to the manufacturer’s instructions and based on their lifestyle or risk factors.

Here are some guidelines:

Kittens between ages of six weeks old (or two pounds) and sixteen-weeks old need a series of three vaccines separated by at least four weeks each.

Adult cats that have never been vaccinated before will require a booster shot every year, or more often if recommended by your veterinarian.

The frequency of these boosters depends on the type of vaccine and its effectiveness against disease.

Cats at high risk for exposure to infectious diseases may need more frequent vaccination than those who live exclusively indoors or only go outside occasionally, such as cats who participate in shows where they come into contact with large numbers of other animals from around the world.

A cat in a boarding facility may require additional vaccinations depending on its length of stay.

Cats that have been vaccinated should receive a booster every year until age five then every three years after that unless your veterinarian recommends otherwise based on your cat’s lifestyle or risk factors.

This will help ensure protection against disease for life.

House cats that have never had contact with other animals may not need as many vaccinations as outdoor ones because they don’t face any severe risks from diseases that can spread through direct physical contact.

As mentioned previously, though, it’s always best practice to get your cat vaccinated against any serious diseases they could contract.

Vaccines for cats are generally given in a series of three injections at two-week intervals starting with six weeks old (two pounds).

The first vaccine protects against the feline herpes virus, calicivirus, and panleukopenia. The second one also includes protection from rhinotracheitis, while the final injection offers additional coverage against rabies and covers more than one year after the initial dose.

Adult cats should receive their vaccines at least once every three years.

They have a more robust immune system than kittens, making it harder for them to get sick from diseases that vaccinations can prevent.

But remember, it’s never too late if your cat is older and hasn’t had any contact with other animals in a while because there’s still time now before something serious happens that might require hospitalization (or worse).


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