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Pets and vaccinations 101

Pets and vaccinations 101
© Pets and vaccinations 101

Just like us, animals require vaccinations to protect them from contracting potentially serious illnesses that can pose a risk to their overall health and quality of life. Vaccinations also cost considerably less than the treatments available for the diseases pets are normally vaccinated against.

To help pet owners better understand pet vaccinations, how they work and why they’re important, Dr. Karla Scott, practice owner of Oro Medone Veterinary Services, shares answers to some common questions that she receives from clients.

Q. How do vaccinations work and are they really necessary?

A. To understand how vaccines work, it helps to first look at how the body fights illness. When germs such as bacteria or viruses invade the body, they divide and multiply. This invasion, called an infection, is what causes illness and triggers the immune system to fight back using the body’s white blood cells.

After fighting off the infection, the immune system remembers how it protected the body against that specific illness, so that it can quickly spring into action if it encounters the same germ again. Vaccines help protect the body by equipping the immune system with the tools to fight off a specific infection before it’s contracted, which can help prevent life-threatening diseases.

Q. What vaccinations should my pet have, and how often do they need to be vaccinated?

A. In veterinary medicine, we classify vaccines into two categories: core and non-core. Core vaccines are strongly recommended for each animal of a specific species, while non-core vaccinations are recommended based on an animal’s lifestyle and potential risks. Sometimes vaccines are recommended for an animal due to an increased risk of a disease in the area where they live. Aside from the rabies vaccination, which is required by law in Ontario for all cats, dogs and ferrets three months of age and over, your veterinarian will let you know what vaccinations are important to protect your pet.

Most vaccinations are typically administered every year at your pet’s annual check up, however, some vaccines require a booster to maintain your pet’s immunity.

Q. Are vaccinations effective and safe for my pet?

A. Yes. Vaccines greatly reduce your pet’s risk of infection by working with the body to safely develop immunity to disease. Sometimes after receiving a vaccination, the body can develop minor symptoms such as a fever. Minor symptoms are completely normal and can be expected as the body builds immunity. Other more serious reactions can occur, but they are rare. If you have questions or concerns about your pet receiving a vaccination, it’s important that you discuss them with your veterinarian.

Q. My pet never goes outside – do they really need to be vaccinated?

A. Yes. Although it’s less likely, indoor-only pets can still come into contact with other disease-carrying animals such as mice and bats. In my career, I’ve personally experienced two separate instances where unvaccinated, indoor-only pets were exposed to bats that tested positive for the rabies infection. To prevent the spread of dangerous illnesses among animals, it’s important that both indoor and outdoor pets receive their species’ core vaccines.

Q. Why does my veterinarian need to perform an exam before vaccinating my pet?

A. It’s important to administer vaccines only to healthy animals. A physical exam helps to detect changes in your pet’s health that can affect the vaccine’s ability to develop immunity. It can also help detect certain types of illnesses that may prevent your pet’s body from developing the proper response to the vaccine or make them feel worse temporarily. For these reasons, your veterinarian will examine your pet and ensure they’re healthy before vaccinating them.

Q. Why is the rabies vaccine required by law?

A. Rabies is a fatal zoonotic disease, meaning it can be transmitted from animals to people. According to the World Health Organization, up to 99 per cent of all human rabies cases are linked to dog bites.

For more general information about vaccinating your pet and other pet care tips, visit To ensure your pet’s vaccines are up to date, and for information about which vaccines are best for your pet, book an appointment with your veterinarian.

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