Pet Vaccinations – Pros and Cons

Recently, I had a client whose dog had a bad reaction to a vaccination. Although vaccinations are now a regular part of vet care for our pets, it’s a topic that has its share of controversy. In this article, I want to talk about the protective value of vaccines, as well as some of the negative effects attributed to them, and what to watch out for if you do decide to vaccinate your pet.

Many of us think of vaccines as a safe and necessary part of pet ownership. In the city of Fremont where I live, pet ownership requires proof of vaccination as part of its licensing system. But, like any medical treatment today, vaccinating pets has its advocates and opponents.

Opposition to vaccines in general has existed since its discovery and use, and in the last few years, more and more vets and pet owners have raised concerns about pet vaccinations and how necessary they are. Some even question their safety, claiming they might actually cause illnesses.
In general, the pros and cons are:


  • Vaccines protect pets against diseases


  • Some vaccinations may have side effects
  • Vaccinations are believed to actually cause illness
  • Vaccinations may cause injection site sarcoma
  • Your pet may get vaccines they don’t need

It’s nothing new or unusual to us to think of vaccines as part of pet ownership. When you adopt a pet, the routine information given to you is that you should take your new pet to a vet for a full checkup and for their shots. Most of us do that without a second thought.

It’s most likely that your vet will examine your pet and give it vaccination shots for diseases such as rabies and distemper. Puppies and kittens are given shots when they are several weeks old and then get “booster” or additional follow up shots later on. Even after our pets reach adulthood, we take them to the vet to get shots annually or every three years.

Vaccines are actually very small doses of the diseases in question, which is supposed to force the recipient’s natural immune system to kick in and fight off the viruses, thus making them stronger and better able to fight off diseases if they are exposed to them in the future. It may even make them immune to the disease altogether.
Although there seem to be more negatives to giving your pet its vaccinations compared to positives, the positive is that vaccines prevent diseases. This is one major point which can outweigh many negatives against it. I am not making a choice for you. That is up to you and your veterinarian. If you would like to read about the core pet vaccinations, you can do so at

Vaccination Controversy

Although vaccines are the conventional and accepted way to prevent diseases in us as well as our pets since its discovery, there is an increasing number of vocal critics of vaccinations.

Some vets and pet owners have claimed that vaccines are the source of immediate negative side effects as well as long-term health issues. Various illnesses are connected to vaccinations, such as asthma, allergies, anemia, digestive problems, cancer, diabetes, arthritis, autoimmune disorders, organ failure, seizures, neurological disorders, and tumors.

There is evidence of sarcoma (cancerous tumors) at the site of injections. All these frequent shots may also be compromising our pets’ health by overloading their immune systems.

Not only do people object to these regular vaccinations as a source of a variety of problems, but some also claim that some vaccinations are unnecessary because of the rarity of some of the disease in question. There are vets who now offer tests to determine the level of antibodies (proteins in the immune system that identify and fight off viruses and bacteria) in animals so that they can decide on the needed vaccinations for individual pets.

Consider Each Pet Individually

I believe the best thing do to is to educate yourself as much as possible about all the vaccines out there, those being given to your pets, and to talk to your veterinarian about the best course of action for your pet.

Vaccinations have proven to be effective over many years of use and I think it’s important to prevent diseases, but keep in mind that each pet is unique and it’s best to determine with your vet the best course of action. A barn cat’s vaccination needs will differ greatly from the pampered lone kitty living in a condo.

The working sheep herding dog will probably need additional vaccines compared to the lap dog that goes outside only for walks and potty breaks. But also keep in mind that vaccinations are not 100 percent effective all the time.

You don’t want to vaccinate when it’s not necessary and you should keep close tabs on what your pet is receiving and how often to ensure maximum benefit and safety. When combination shots are given, ask what is contained in the shots and get an explanation of each component.

When vaccination shots are given, talk to your vet about where the shots are administered and why. After vaccinations, observe your pet to catch any signs of negative side effects or an allergic reaction. If your pet starts to vomit, has diarrhea, swelling, or otherwise acts ill, lethargic, or in pain shortly after receiving a vaccine, take your pet in to see the vet. It’s much better to be safe than sorry when it comes to the health of your pet.