Cat Vaccination - Feline Vaccination Facts & Why Cats Need Them

What are cat vaccinations?

Vaccinations, in general, are any time that you give an animal, or a person for that matter, a modified version of a pathogen, usually a virus or a bacteria, in hopes of stimulating their own body's immune response. You want their body to produce antibodies against that substance. So therefore that way, if they're ever exposed to it another time down the road, they already have immunity towards that organism and can better fight it off.


Dr. Scott Broussard
The Waggin Train Veterinary Clinic

Are cat vaccinations important?

Yeah, I think they're very important. Why? Because you have no idea what your cat is going to be exposed to over the course of its life. We see animals at times that come in for illness and they've never been vaccinated. We see things like leukemia, or what we call feline distemper—those kinds of things that they're completely at risk for if we’ve never seen them before, as they have no way to fight the illnesses off immunologically.

So, yes, I think they're extremely important—particularly at a young age, you want to start that animal off right to give them a good titer of antibody protection.

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

I guess the way I would answer that is what most people refer to as core vaccinations. Core vaccines are the bare minimum. They're the essentials. They are the things that are the most important, the most life-threatening, or perhaps the most likely that that animal is going to be exposed to.

In cats, I look at it as two core vaccinations. One of course is rabies. We all know about rabies, I'm not going to go into depth about that here, but that is considered a core vaccination for cats. The other one is what we typically call FVRCP. Now, what that stands for is Feline Viral Rhino Tracheitis, Calicivirus, and Panleukopenia. They typicall come in combination. For every cat that I see, whether indoors, outdoors, or a multiple cat household, I'm going to recommend those two as my core vaccines all the time.

What is the vaccine schedule for kittens?

With kittens, it's similar to that in dogs. So what that means is they come in for a series of vaccinations, usually separated by about three to four weeks apart. You will give an animal the first set usually in the six to seven-week range and, as I said, every three to four weeks thereafter until they're about four or so months of age.

There is no exact science with this. A lot of veterinarians do it differently, but my ideal schedule would be six weeks, nine weeks, 12 weeks, and then probably 15 or 16 weeks, and then I'm finished vaccinating a kitten. You want at least two sets of vaccinations after 10 weeks. That has to do with antibody production. I don't have time to explain all the ins and outs of that now, but it has to do with the way they produce antibodies. Then once those kitten vaccines are done, then it's at least annually thereafter.

Do adult cats need vaccinations?

Well, adult cats fall into the annually thereafter category. So assuming that an adult cat has had vaccinations as a kitten, then they would require annual revaccination for most of those pathogens and, in my opinion, they should do so for life. If an adult cat comes to me and has never been vaccinated, I'm going to do one set now, and then I'm going to booster that in three to four weeks, and then continue to vaccinate them annually after that.

Do senior cats need vaccinations?

So, there is a lot of debate on this one. Some people come in and they say, well, "My cat's 12 or 14m and they've had vaccines all their lives. Do they really need to continue doing it?" It's a fair question, and it's a tough one to answer. My answer, do I vaccinate my own cats as they continue to age? That answer is yes, I do. The old expression, "An ounce of prevention is worth a pound of cure" rings true to me.

Does that mean that the cat is going to be just a susceptible at 12 years of age as it was at 12 weeks of age? No, of course not. They have antibodies. Those antibodies should stand up and do their job, but think about elderly people. Sometimes their immune systems are not as viable as they once were.

Let's look at COVID, for example. Who's the highest risk population? It's senior people, especially those with underlying medical conditions but, in general, elderly people are more at risk. How would a cat be any different? As a cat ages, sometimes their immune system is weaker than it used to be as a young, vibrant cat.

So, it's a long answer to tell you that yes, I do believe that senior cats should continue to be vaccinated. Now, if you want to cut those back a little bit and not give them as often, if you worry about illness because of the vaccine, or you want to separate them, I have no quarrels with that, but I do think it is important to continue to vaccinate them to ensure that they're protected.

Are there risks or side effects associated with cat vaccinations?

There's always a risk with vaccines. I can't sugarcoat that. Is it common? No, not terribly common at all. But is it possible? Yes, it is. Any time you introduce a foreign substance into the body of a living creature, you run the risk of that substance causing a volatile reaction.

The most common thing that we see would be an allergic reaction or an anaphylactic reaction where they might break out in hives, they might itch, or in some cases they’ll experience vomiting or diarrhea. Things like that are possible. To be honest with you, right now, as I answered this question, I would be hard-pressed to tell you that last time I saw a cat that reacted to the vaccines that we give. That's truthful, but is it possible? Yes, it is.

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

I believe, yes. Why? How are they going to catch things when they're indoors? Are they going to get bitten by a rabid animal when they're in your living room? No, probably not. But what happens when that door stays open or the window screen gets torn and the cat jumps outside and is in the neighborhood for an hour, a day, a week? That's when the importance of vaccines really shows itself.

Is it as likely for an indoor cat to get some of these things we've touched upon as it would be for a stray cat that's roaming? Of course not. No, it's not, but you never know what the future holds. It takes one accident, one escape, one runaway, one broken pet carrier as you're walking to the car, anything like that, and that cat can escape, and the cat is now unprotected out in the world.

It's just a gamble that, personally, I'm not willing to take. So now maybe an indoor cat, we don't do as many vaccinations because they're not at risk for as many things if they are primarily indoors. But again, refer to one of the first answers I gave when I talked about core vaccinations. That's when I think those core vaccinations, like rabies and the Viral Rhinotracheitis are imperative.

Why is it important to avoid missing a cat vaccination?

Well, firstly, it's very important as a kitten. When you're doing the spacing of vaccines, you don't want to give them any closer than three weeks apart because the immune system doesn't have a chance to form what's called an anamnestic response and produce adequate antibodies to that second or third set. So, they have to be at least three weeks apart. The flip side to that is you don't want them to be more than six weeks apart.

Again, this is in the kitten stage. Any more than six weeks and the antibody production will spike and then dwindle to the point where if it's beyond six weeks, then you give them another booster vaccine, it's almost like starting over again. It has to be in that three to six-week window to have an adequate anamnestic response.

As an adult, does it have to be 12 months on the nose? No, not really. I think it's wiser to do so, and there are certain legal things. For example, the rabies vaccine is mandated that it's given every year where I practice. So to stay in accordance with the law, it's why we try to aim for once a year. But if you're a little late, or you can't get the cat in, or there's some other illness that prevents you from vaccinating, it's not the end of the world. Just bring them in when you can, and when the cat is healthy and stable. I think it's wise to boost them as soon as you can after that.

If you still have other questions and you'd like to reach out to us, you can call us directly at (337) 223-9581, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as fast as we can.

Cat Vaccination - FAQs


Dr. Scott Broussard
The Waggin Train Veterinary Clinic

Can my cat have an allergic reaction to a cat vaccine?

The short answer is, yes, they absolutely can. Anytime you put something foreign into the body of a living creature, there is a potential for a reaction to that said something foreign. Vaccines are no different. You're putting a modified form of a virus, or in some cases, bacteria, into that cat and sometimes their immune system might go overboard with its reactions towards that particular item. So yes, they can have reactions.

Can my cat get cancer from vaccinations?

Aha, yes. The unfortunate answer is yes, they can. There is an injection site tumor called a fibrosarcoma that they can sometimes develop. I have been in practice for 21 years and I think I have seen three in 21 years. Is it common? Obviously, no, it’s not common at all. In fact, there've been a lot of changes to vaccines in probably the last 10 to 12 years or so, and I'm just randomly picking that timeframe, but around there, to where they changed it. It used to be due to what's called the adjuvant, the carrier in the vaccine. They would put an additive in vaccinations to stimulate the immune system and it's thought that a lot of the adjuvants in some of the vaccinations, particularly the old leukemia vaccines, were thought to be the ones to do that. To my knowledge, that adjuvant has been changed or taken out completely. I don't know for certain, but I can tell you that I have not seen a reaction that way in many, many years—it’s probably been double-digit years since I've seen one of those cases, but it is possible, unfortunately.

Is it safer to opt out of any non-core vaccinations?

Good question. Non-core vaccinations would be anything that has to do with the lifestyle of your cat. The core vaccinations would be things like rabies, rhinotracheitis, panleukopenia, those things. I give those to every cat. The non-core vaccines would be things like FIP or feline leukemia.

To answer your question of whether it's safer to opt out of non-core vaccines, I suppose you could say that's true, but only in the sense that I'm not about vaccinating every cat for every disease that's on the planet if they're never going to be exposed to them. If I have an animal that's indoors 24/7 in a double-locked room and is never going to step foot outside and no other cats are coming in, would I be fine with just doing those minimal core vaccines? Yes, I would. Of course, I would. If you're at all unsure if it's one of those where, "Well, he goes outside every now and then," or, "Well, he loves to run out the front door every time we try to go outside," then I would absolutely do the additional vaccines, like feline leukemia and what have you, to keep that cat protected because you don't know what they're going to be exposed to.

I think in the light of this discussion that we're having about reactions to vaccines and their safety, my honest answer would be if that cat never has a risk of being exposed to what you're considering vaccinating for, then I ask you, "What's the point? Why do something that they'll never be exposed to?" That's my answer there.

If you still have other questions and you'd like to reach out to us, you can call us directly at (337) 223-9581, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as fast as we can.