Are We Vaccinating Our Dogs & Cats too Frequently?

Vaccinations are critical for maintaining good health; they can provide an individual with immunity to a variety of serious diseases. This has revolutionized modern medicine for humans – the first great achievement being the complete eradication of small pox by vaccination.

Like humans, animals too are benefitting greatly from vaccinations. It is thanks to animal vaccination that the spread of serious diseases, such as rabies, has been controlled. As a matter of fact, one of the very first things to do when adopting a new pet is to take them to the veterinarian for a checkup and vaccines.

Recently however, more and more arguments are coming forward suggesting that we may be vaccinating our pets too much, but is this a bad thing?

What is Vaccination?

We should all be familiar with vaccination, after all, the government spends millions on vaccination plans to ensure that kids get vaccinated at school at an early age. But what is in a vaccine? How do they work?

Vaccines contain a weakened or dead version of a pathogen. Some vaccines just contain bits of a pathogen! All produce the same effect however and that is to stimulate the immune system. Because the pathogen is either dead, or weakened, you get the benefit of developing immunity to the pathogen without getting the disease.

What is Immunity?

So vaccines help you develop immunity, but what exactly is immunity and how do they do it?

If you are infected with a pathogen you have never been infected with before, your body (and this is the same for our dogs and cats) responds slowly. This is because it needs to identify the invader and build up an army of white blood cells that then go on to kill the pathogen. Because this process takes a relatively long time, the pathogen is able to reproduce and make you sick.

If the same pathogen was to infect you again, your body remembers the invader and having already identified it – your body is able to rapidly produce the army of white blood cells it needs to destroy the invader before it is able to reproduce in large numbers. This is great news as it means you don’t get sick! (Or if you do, it isn’t as bad as the original infection).

Vaccines simulate the original infection, but the low, weakened dose allows your body to identify the pathogen with a minimal risk of it making you sick.

Vaccination in Dogs & Cats

Normally, we vaccinate our dogs and cats shortly after birth and then take them in for a booster after around a year. We are sometimes advised to continue bringing them in regularly to maintain their immunity against disease, but is this the right advice?

Broadly speaking, there are two main types of vaccine for dogs and cats; ‘core’ and ‘non-core’. These can differ between areas around the globe, but generally speaking, the vaccines below are a good example of typical core and non-core vacciantions:

Core Dog Vaccinations:

  • Rabies
  • Canine Distemper
  • Canine Parvovirus
  • Canine Hepatitis Virus

Non-Core Dog Vaccinations:

  • Kennel Cough
  • Canine Parainfluenza Virus
  • Lyme Disease
  • Leptospirosis
  • Canine Coronavirus
  • Many others…

Core Cat Vaccinations:

  • Feline Influenza (Viral Rhinotracheitis)
  • Feline Calcivirus
  • Feline Panleukopenia Virus
  • Rabies

Non-Core Cat Vaccinations:

  • Feline Leukemia Virus
  • Feline Immunodeficiency Virus
  • Bordetella (Kennel Cough)
  • Many Others…

The Problems with Current Vaccination

Whilst it is a great thing that we have all these options available to us when considering vaccinating our pets, it does bring up a few problems. For instance, if you wanted to vaccinate your dog with all the recommended vaccinations and additional non-core vaccinations, you could end up regularly visiting the vets and have a large vet bill to go with it!

To deal with this, vaccine companies have created ‘multivalent’ vaccines – vaccines that are able to vaccinate a dog or cat against multiple diseases with only a single injection. Multivalent vaccines can introduce new problems however. In the USA, some multivalent vaccines now contain up to 8 different vaccine agents!

At present, multivalent vaccines are widely accepted, but increasing evidence suggests that they put excess strain on the immune system.

Giving multivalent boosters could be a problem due to the variations in the diseases they immunise against. For example – one of the vaccine agents might give immune protection for one disease for a year, whilst another may protect against a different disease for 10 years! If the multivalent booster is given each year, then it is just putting the immune system under unneeded stress.

The main problem with vaccinations in both dogs and cats however, is that they are not treated as individual patients. Whilst a leptospirosis vaccination may protect one dog for a year, it may protect a different dog for two or more. Factors that affect the strength of the immunity provided by a vaccine include:

  • The type of vaccine
  • How the vaccine is stored/preserved
  • The age of the vaccine
  • Whether additive were added to the vaccine
  • The number of previous vaccinations given to the dog or cat
  • The breed and genetic makeup of the dog or cat
  • The pet’s age
  • The health of the pet
  • The pet’s diet

All these factors are something to consider – but even though we know that a vaccine can provide different pets with varied levels of immunity, it is fairly difficult to check when a booster is needed.

So, Are We Vaccination our Dogs and Cats too Frequently?

Unfortunately, we probably are. The yearly vaccinations, often recommended by vets are simply too frequent for most vaccine types and can put excess stress on our pets.

A 3 or 4 year vaccination schedule would be more appropriate in most cases with the exception of kennel cough and leptospirosis – which are known to require more frequent vaccination (around one a year).

Why is Frequent Vaccination a Problem?

If vaccines are safe, why should we worry about vaccinating too frequently? Well although, vaccines have an excellent safety record, they are not without their side effects. Although rare, frequent vaccination increases the probability of your pet developing these side effects, including:

  • Allergic reaction to the vaccine
  • Nerve damage
  • Bone/Muscle wasting
  • Swelling
  • Fever
  • Lethargy
  • Ulcers

Cases of vaccine induced conjunctivitis and alopecia (hair loss) have even been reported! Although there is always risk, remember that side effects are generally rare and vaccines have a very good safety record!

Your Thoughts

Do you think we vaccinate our pets too much? Or do you think that there is little harm in yearly vaccinations – the side effects are rare after all and there is still little evidence to suggest that over-vaccination is truly a bad thing.

About James Watts

BSc Bioveterinary Science. Editor of PetSci. When I'm not writing, learning, discussing, or reading about animals, you know it's the weekend! Currently developing PetSci HealthTrak, the fast and easy way to monitor your pet's weight and calorie intake. HealthTrak offers a simple way to track your pet's progress, helping them achieve a healthy weight and a long, happy life.

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  1. I have noticed some vets (like mine) moving away from recommending all non-core vaccinations just because. My vet asks me about my dog’s daily activity (like, how often do I go to dog parks) and tells me what I should have based on that.

  2. Hi There,

    I think we should get less shots cos I’m the one getting them and I don’t like them!! But I’m a little biased!! 🙂 Like I get any say anyway…… doh!!

    Have a fun day,

    Your pal Snoopy 🙂

  3. Personally, I don’t think all pet vaccinations are really necessary. Rabies shots, etc of course are needed. But a booster shot every once in a while I don’t feel is absolutely necessary. I have 4 cats and they are all perfectly healthy, even without their routine shots. My family has had numerous pets for years and years without the typical vet routine shots and they have been normal and healthy. It’s a matter of opinion, though of course! Thanks for the info!

  4. Cats are suffering kidney failure because of yearly vaccines. Because large immunocomplexes are damaging their small blood vessels in kidneys. Vets don’t vaccinate their pets yearly. But rarely will advise You the same! It’s money! Ask for serology tests on antibodies levels!

    • it’s not true, i’m a vet and most of cats suffering kidney failure in my nearby are cats not vaccinated at all, feeded poor quality food from chain stores as a first case of that problems, and are outdoor cats so most of them have a toxic renal failure ie from glycol car coolers on their fur from cars or from eating not controlled toxic plants

  5. Like a caring pet owner, I had my cat vaccinated very year. Immediately after her 13th vaccination a lump appeared on the injection site. My vet said it was too near the spinal column & nervous system too operate to remove. I told him that I did not want samples taken as that would encourage the cells to mutate. He finally said he wanted to discuss the problem. I told him that I knew it was cancer & he agreed. He gave her 3-6 months.
    I did my best to care for her & she lived for a further 11 months,.
    I have since looked into annual vaccinations..
    Some injections would last for 3 years or more. However, the companies producing these want profit from annual injections. Vets also profit from the annual injection cost. So we are never told that 3 years would be covered..
    Surely the animal’s life should be looked at & vets should advise cat owners (& dogs as well) that there is no medical reason, in many instances, for the animal to have an annual vaccination..

    What is more important? – the life of our pet? – or company PROFIT.??

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