Cat Vaccinations

You've taken the first step in being a proactive pet parent by researching cat vaccinations. You surely want your pet to have a long and healthy life, and vaccinations are a huge contributor to your cat's wellness. It makes sense that you have questions about what vaccinations are needed and when your cat should get them. At GeniusVets, we firmly believe that petcare information should come from veterinarians and not from the internet, as anyone with a computer can share information these days, and it's often not correct. That’s why we’ve taken the most common cat vaccination questions, sent these questions to renowned veterinarians across the U.S., and compiled their replies to get you useful information that you can trust.

While we've sourced all of the cat vaccination information and recommendations below directly from leading veterinarians across the country, please make sure to seek out the advice of your own veterinarian or find a trusted vet near you using the GeniusVets Directory.

What exactly are cat vaccinations?

A vaccination is an injection of a mixture of molecules that will help stimulate an immune response to a specific disease. The cat’s body will recognize the pathogen and fight it off. A common one would be the rabies vaccine. In the rabies vaccine, there are parts of the rabies virus, but not the entire virus. It's not an active or live virus, but parts of the virus that we inject along with other chemicals into your cat to help them start to build antibodies, protect them against exposure to rabies, and keep them safe. We also have vaccines for many various diseases in cats. There is the feline leukemia vaccine and what we call the distemper vaccine, a combination of several diseases that can cause feline distemper and various respiratory diseases.

Are cat vaccinations necessary?

Yes, vaccinations are necessary as they can prevent fatal and zoonotic diseases. Rabies is a disease that, if your cat were to contract it, could be fatal to your cat, and if you were to contract it, it could be fatal to you. Other diseases may not be zoonotic or transmissible to humans, but they could still be very dangerous or fatal to your cat. State law requires rabies vaccinations for all cats and, even if they’re inside 100 percent of the time, you should get your cat vaccinated against rabies. Unfortunately, bats can get into just about any house and bite your cat, possibly infecting them with rabies. You can't always tell if you or your cat have been bitten, and that's still a potential vector for rabies. We must keep all of our pets safe so that we keep ourselves safe.

Most veterinarians recommend doing distemper shots every three years until cats are about anywhere between 8 to 10 years old—again, even indoor cats, as you need to protect them from exposure to disease through screens. For cats going outside, your veterinarian will also recommend the leukemia vaccine because that is a disease that we can't cure, and it can cause several health problems. Leukemia is transmitted from cat to cat, usually through an aggressive activity like scratching or biting.

What vaccinations are typically recommended, and what are they for?

Rabies vaccines are required for all domestic cats, dogs, and ferrets in the United States. Rabies vaccinations start when they're a kitten and are continued throughout their life. Another vaccine is called feline viral rhinotracheitis, calicivirus, and panleukopenia, and that is your constellation of upper respiratory infections that cats can get. Because these infections are viral, you can bring them in on fomites on your jacket or other things you bring in from the outside. So even if your cat's indoor-only, we do recommend protecting them against these viral infections every year. Sometimes plans change between kittenhood and a year old, and we end up letting kitties out, or they get out because they're wily little creatures, and we want to make sure that they're safe. Finally, we typically vaccinate for the feline leukemia virus, transmitted by bite wounds from cat to cat. That’s more of an issue for outdoor cats.

Here are the most recent cat vaccine guidelines from the American Animal Hospital Association (AAHA).

What is the vaccination schedule for kittens, adult cats, and senior cats?

We typically recommend doing a distemper shot for kittens every three to four weeks, starting between six and eight weeks of age until about 14 to 16 weeks of age. We do several boosters because the antibodies that kittens receive from their mother through the milk can interfere with the vaccine's effectiveness. How long those antibodies stay in their system varies from kitten to kitten. Based on studies, we know that if we continue to vaccinate until they're 14 to 16 weeks old, the vast majority of kittens will get a solid immunity to the diseases we're vaccinating for by 16 weeks of age. Rabies is such an effective vaccine, and there is not a lot of maternal antibody interference, so a single vaccination - usually between 12 and 16 weeks - is adequate. We typically start between eight and 12 weeks for leukemia, and two vaccines as a booster series generally are enough.

As we get into the senior years, most veterinarians will start to reevaluate vaccination schedules based on lifestyle and whether the cat has had any vaccine reactions in the past. For indoor cats that we are not being fostered or that don’t have exposure to outdoor cats and there are no plans for new cats to be added to the household, most vets will discontinue the distemper vaccination between eight and 10 years old. If we have a relatively sedentary outdoor cat, most vets will stop the leukemia vaccines around 10 to 11 years old. We maintain just rabies vaccines in elderly cats in most situations.

Are there risks or side effects associated with cat vaccinations?

There are risks with any injection that we do, but they are minimal. There’s always a risk of soreness at injection sites, swelling, and bleeding with any vaccine. On infrequent occasions, we can see an anaphylactic or an allergic reaction. This would typically happen within 30 minutes of the injection, and it's very apparent, and you would see wheezing, facial swelling, vomiting, or diarrhea. If you ever notice any of these sorts of signs after your cat's been vaccinated, you want to get them back to your veterinarian as soon as possible so that we can treat that reaction. Sometimes cats will get quiet for two to three days after a vaccination, which usually resolves on its own.

There's also a tiny subset of cats (the highest percentage reported is about .01 percent) that seem to have a genetic predisposition to developing a tumor called a vaccine-associated or an injection site-associated sarcoma. These cats with the genetic predisposition are more prone to developing a tumor at the site of injection. It doesn't necessarily have to be with the vaccine, but that's the one we see the most. Despite its rarity, one of the things that we do to mitigate this risk is we give the vaccinations as low on the leg as possible so that if the cat starts to develop a growth there, it's easier to remove than if it were between the shoulder blades or over a hip or an area like that. This complication is also covered by the vaccine manufacturers so that they would pay for any potential treatment. That goes for any complication associated with the vaccines, as they're all guaranteed by the company that we use, so you know that you're going to get good care in any situation, and we monitor those situations closely.

If my cat is going to be strictly indoors, do they still need to be vaccinated?

Yes, certain diseases like the feline leukemia virus can be spread by saliva alone, perhaps if another cat is introduced into the environment. Rabies is also still a risk even if your cat never goes outside. We also recommend distemper in most cases, too, as many of us keep our windows open in the summertime, and some cats go out and about. We want to keep any potential risk factors minimized by keeping those indoor kitties vaccinated.

Why is it important to avoid missing a cat vaccination?

If we're not keeping up with those boosters, the immunity may wane over time, and with potential exposure, we may or may not know if your cat is going to be protected. If you miss a vaccination, you are altering the ability to build up as much immunity as possible against these diseases.

If you have any further questions about cat vaccinations, ask your vet. If you don't have one yet, we can help you find a local veterinarian!