In the spring of 2020, Kelly Kerlin’s veterinarian gave her rescue dog, Finley, vaccinations against Lyme disease and leptospirosis, administering them behind the dog’s neck at the top of her back. Finley soon developed a lump slightly smaller than a golf ball.
“We couldn’t pick her up without her screaming in pain” for over a month, said Ms. Kerlin, who lives in Excelsior, Minn. When it came time for Finley’s vaccines in 2021, the veterinary technician was getting ready to give those shots again, but Ms. Kerlin refused. When she took her children to be vaccinated, she said she received written information about potential side effects. “I can’t remember them ever talking to me about what a side effect would be for my dog,” she said.
Ms. Kerlin said she isn’t an anti-vaxxer and her dog has received shots for other diseases, like rabies and Bordetella. But for these particular vaccines, she didn’t feel that the risk of the side effects outweighed the benefits.
Still, she’s not alone in her worries about vaccines — opposition to pet vaccines has grown in recent years, fueled by an anti-vaccination movement in humans that has spilled over to animals. A study published in The Canadian Veterinary Journal last year found an association between the organized movement against mandatory vaccines for children and vaccine-resistant pet owners.
“The anti-vaccination movement was a cause for concern before Covid,” said Lori Kogan, one of the study’s authors and a professor at Colorado State University who studies human-animal interactions. “It’s certainly a cause for concern now.” Kogan is also conducting a follow-up study exploring pet vaccine hesitancy in the wake of Covid-19, with data due within the next few months.
A study published last April found that many vaccine skeptics appeared to link treatment for their dogs with concerns that childhood vaccines cause autism in humans — a theory without scientific merit. That conflation often occurs because many people consider their pets to be part of their family, said Dr. Jeanette O’Quin, an associate professor at Ohio State University. The phenomenon is one that psychologists have long documented, and a recent study indicated that such feelings are even stronger among pet owners who don’t have children.
“It’s a good time to be a cat or a dog in the U.S.,” Dr. O’Quin said.
Whether you just adopted your first animal during the pandemic or are a seasoned pet owner, here’s what you need to know about vaccines and keeping your pet safe.
Why should your pet be vaccinated?
Pet vaccine hesitancy is worrisome, vets say, since vaccines not only protect individual cats and dogs but also eliminate widespread diseases. And, some diseases, like rabies and leptospirosis, can infect people, too.
Also, vaccines don’t need to be administered to pets as frequently as in years past, according to Dr. David Emery, an assistant professor at Michigan State University College of Veterinary Medicine. Over the past two decades, many vets developed a reputation for over-vaccinating pets, Dr. Emery said. But significant technology improvements mean that vaccines are now more effective and often needed only once every three years instead of annually.
Which vaccines are necessary for your pet?
Pet vaccines are grouped into two types: core and non-core. Core vaccines are recommended for all pets, while non-core vaccines are recommended based on a pet’s unique medical history and lifestyle. Many core vaccines are given together in one dose, minimizing the frequency of such injections.
Almost all states require a rabies vaccine for cats and dogs since the disease is fatal in both animals and humans. The parvovirus vaccine is another important one, according to Gail Hansen, a representative from the Humane Society Veterinary Medical Association. The shot targets a gruesome disease that especially affects puppies and causes death that “is just painful and horrible to watch,” Ms. Hansen said.
What should you ask your vet about non-core vaccines?
Not all vaccinations are necessary for every pet. One key question to ask your vet, according to Dr. Jose Arce, president of the American Veterinary Medical Association, is: What conditions are prevalent where I live? (If you don’t live in an area where Lyme disease is prevalent, for example, that vaccine is usually unnecessary.)
Another key question: What is your pet’s lifestyle? Does your cat go outdoors where it’s exposed to more diseases?
When two of her previous cats were 19 and 17, Sharon Kennedy asked her vet if it was necessary to continue getting them vaccinated. “It was so traumatizing to the cats bring them in,” she said.
The vet told her that since they were indoor cats and had built up enough immunity, the shots weren’t necessary. Ms. Kennedy, who lives in Brea, Calif., said she has yet to vaccinate her 15-year-old cat, Kiki, who is afraid to go outdoors and is therefore not at risk for exposure.
Recommendations can also vary by vet. Even indoor cats can be at risk if they’re not vaccinated, said Dr. Carolyn Brown, vice president of community medicine at the American Society for the Prevention of Cruelty to Animals. Some diseases can be spread indirectly, such as if family members introduce viruses to the home through contact with other cats or their shoes or clothing.
Another question is: How is my animal’s overall health? If the animal is old, has low risk for exposure and has underlying health conditions, it may not always make sense to vaccinate, Dr. O’Quin said. And if an animal has a history of anaphylaxis or immune mediated disease, Dr. Emery said he would think twice about vaccinating the animal.
How can you safeguard against side effects?
Side effects after pet vaccinations are usually very mild, and severe adverse effects are uncommon. There can be soreness at the injection site, a low-grade fever or lethargy, which indicate that the immune system is working. If a pet has had an adverse reaction to a vaccine in the past, Dr. Arce suggested asking your vet about preventive measures, such as administering Benadryl shortly before a vaccine dose.
He also recommends monitoring your pet for the first few hours after it’s vaccinated for the first time. If your pet shows symptoms like difficulty breathing, facial swelling, vomiting or diarrhea, call your vet immediately.
Should you get your pet tested for antibodies?
Pet owners who are concerned about regular vaccines can opt for titer testing, which can measure whether animals have sufficient antibodies from previous core vaccines. Animals with high enough antibody levels don’t need booster shots, said Dr. Laurie J. Larson, director of the Companion Animal Vaccines and Immuno-Diagnostics Service Laboratory at the University of Wisconsin-Madison School of Veterinary Medicine.
But other veterinary experts disagree — such testing has “no real benefits,” Dr. Hansen said. It’s expensive, and rabies titers can’t legally be used instead of required rabies boosters. Titer testing is best limited to pets that have autoimmune disorders that could complicate vaccination, Dr. Emery said.
What if you can’t afford vaccines for your pet?
The cost of veterinary care in America has risen in recent years, partly because of higher demand and new technologies, making it difficult for some people to afford vaccine costs.
Some animal shelters and veterinary hospitals offer vaccines at low costs, Dr. Arce said. Government agencies, charitable organizations or pet retailers also sometimes host low- or no-cost rabies vaccination events. Through a partnership with ShotVet, for example, PetSmart offers vaccination services that are 30 to 40 percent less expensive than normal costs.
Overall, Dr. O’Quin said she hopes pet owners commit to getting their pets vaccinated. “The diseases that vaccines prevent can be fatal, and even when they’re not, they cause a lot of pain and suffering,” she said. “It’s heartbreaking for us to see these cases knowing that they could have been prevented.”
Julie Halpert is a journalist who covers parenting, science, health, retirement and the auto industry.