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Pet Vaccine Primer: Concerns and Safety, Part Two

cat health dog health pet health


Vaccines are a pretty controversial topic. The conversation has spilled over into the pet world, leaving a lot of questions and concerns over safety and options. If you missed our Pet Vaccine Primer, Part One, please check it out. We covered vaccine basics for those who aren’t sure how they work in the pet world. We also detailed the types of vaccines recommended for cats and dogs, core versus recommended vaccines, and the vaccine schedule. In this piece, we dive into specific risks and concerns surrounding particular vaccines as well as options pet guardians have.

Vaccination Risks and Concerns

Vaccinations are built to stimulate our immune systems so that we can fight the disease should we come into contact with the virus in the future. The problem is, everyone experiences varying levels of stimulation. In most cases, the reaction, if any is detected, will be mild. Examples include soreness at the injection site, fever, sluggishness, loss of appetite, slight swelling, and diarrhea. These symptoms are only temporary, and we can help our cats and dogs through the discomfort with medications or at-home remedies.

Immune System Response

In some cases, our cat- and canine-companions may have temporary symptoms that are more serious and require a follow-up vet visit for treatment. These include those already listed as well as high fever, vomiting, difficulty breathing, and seizures. This type of reaction is usually the result of the vaccinations being administered at the same time as an existing illness or a previously undetected disorder that has already compromised the immune system.

Combo Shots and Extended Series Options

Pet Vaccine Primer: Concerns and Safety, Part Two | Vet OrganicsIt could also be that too many vaccinations were administered at once in what’s called a ‘combo shot’ that creates more of an assault on the immune system. The combo shot is something that won’t adversely affect most cats and dogs. Plus, it often saves money for the family because it means fewer office visits. However, if combo shots are a concern, pet guardians can absolutely request that vaccines be spread out over more time to help avoid the possibility of a reaction. We just need to keep in mind that this extends the period of risk and susceptibility to disease, so we’ll need to keep our puppies and kittens inside and won’t be able to socialize them as early as other pet guardians.  

“If combo shots are a concern because of the possibility of a stronger immune system reaction, request they be spread out over a longer period of time. Most vet offices will not charge for an office visit for each vaccination because the shot can be quickly administered by a technician.”

Allergic Reactions

In very rare cases, they may have an allergic reaction to the vaccine. The prognosis is extremely good in animals with an allergic reaction to vaccines. As long as they are brought to the vet quickly for treatment, survival rates are high. In these cases, vaccine waivers are available to allow guardians to continue to care for their cat or canine, even though they may not have the required core vaccinations.

Cancer And Vaccines

Pet Vaccine Primer: Concerns and Safety, Part Two | Vet OrganicsMany wonder about the possibility of cancer-causing vaccinations. Cancer is only documented in cats after receiving vaccinations with a chemical additive called “adjuvant.” Scientists believe this chemical is the culprit because a statistically significant number of cats developed tumors between their shoulders at the injection site. For this reason, the injection site for this vaccination has been relocated, as standard practice, to the legs so that tumors can be removed if they develop. For those concerned about this development, look for cat vaccines labeled “killed” or “inactivated.” Vaccines with those labels will contain adjuvant. Instead, we can ask our vets about vaccines labeled “attenuated” or “recombinant,” which do not contain adjuvant.

Vaccine Titer Test

Finally, educated pet guardians will ask for a Vaccine Titer Test. This is a test that vets can use to determine whether a cat or dog has adequate immunological protection left from previous vaccinations. It measures antibody levels and only requires a single blood draw. The specific titer test that is often recommended to measure the immune system response to vaccines is called the indirect immunofluorescent antibody (IFA) test.  

We hope this has provided some clarification about the real risks involved with vaccines as well as actionable solutions that help our fellow pet guardians understand their options and regain a sense of understanding and control over the health and well-being of their cat- and canine companions. Watch for future articles about each of the core dog and cat vaccines, what they are for, what to expect, and how they are administered.

Michelle Lievense

Michelle is a writer and ghostwriter, specializing in wellness, sustainability, and global social change. She is particularly fond of serving ethical organizations who contribute to a better life for people and animals through humane and environmentally responsible missions. At Vet Organics, Michelle uses her time as a vet tech, her academic studies in animal science and behavior, and nearly a decade working on a ranch teaching animal husbandry to write on a variety of cat and canine health topics. When she isn't writing, Michelle can be found hiking in the mountains of Colorado with her dogs or snuggled up with a good book and her cats.

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