Vaccine hesitancy gives some US dog, cat owners cold feet

Updated January 25, 2024

While COVID-19 vaccines contributed in critical ways to resolving the pandemic, they also became a divisive and contentious issue, leading to a decline in some people’s confidence in vaccines overall.

Spikes in vaccine hesitancy often coincide with new information, new policies, or newly reported vaccine risks, according to a July 2022 study in the New England Journal of Medicine. Some variability is attributable to other factors such as a decline in the public’s trust of experts, preferences for alternative approaches to health care, political polarization, and belief-based extremism.

But are attitudes towards vaccines for humans connected to those toward pet vaccines as well? A recent study published this past November in the journal Vaccine looked at that very question and found they are indeed closely related.

“We find that the vast majority of cats and dogs are vaccinated. However, a substantial minority of pets is not, particularly for cats and non-core vaccines,” the authors wrote. “We find that attitudinal measures of human and pet vaccine hesitancy are closely related to each other. Moreover, they are strong predictors of vaccine behavior. Measures of vaccine hesitancy are also strong predictors of support for vaccination mandates.”

The connection between attitudes toward human and pet vaccines and how those of some people are changing is forcing veterinary professionals to more frequently explain the benefits of vaccines for pets. This can be particularly concerning because a reduction in vaccination increases the risk of spread of dangerous diseases among both humans and animals.

Spillover from client concerns

While vaccine hesitancy isn’t a new concept, the pandemic seems to have further impacted how segments of the population feel about vaccines not only for themselves, but also for their dogs. Another study reported in the journal Vaccine appears to be the first to formally quantify the prevalence, origins, and health policy consequences of concerns specifically about canine vaccination.

The survey was conducted by Boston University School of Public Health and captured responses from 2,200 dog owners in the U.S. between March 30 and April 10, 2023. Results show that nearly 40% of the responding dog owners believe canine vaccines are unsafe, while more than 20% consider them ineffective, and 30% think they are medically unnecessary. Notably, about 37% of the dog owners surveyed believe canine vaccination could cause autism in their pets, despite a lack of scientific evidence supporting this claim.

These dog owners who distrust the safety and effectiveness of human vaccines are also more likely to hold negative views about vaccinating their pets. This is known as “vaccine spillover,” and more than 50% of dog owners responding to the survey expressed hesitation in vaccinating their pets against rabies and other diseases.

Simon F. Haeder, PhD, is an associate professor in the Department of Health Policy and Management at the Texas A&M University School of Public Health. He was the lead author on another study in the journal Vaccine that found attitudinal measures of human and pet vaccine hesitancy are closely correlated and serve as strong predictors of vaccination behavior. He first became curious about the issue after taking his dog to the veterinarian.

“It has never occurred to me not to vaccinate my dogs against those diseases,” Dr. Haeder said.

In addition, Haeder added that there seemed to be a set of cat owners who do not vaccinate their cats, even against rabies.

“As my study showed, it is not the case that these cats are not exposed to other cats. This holds the potential for some substantial outbreaks for many diseases but, obviously most concerning, for rabies,” he said.

As a dog owner, some of the results of the national survey surprised him, specifically the number of dogs not vaccinated for rabies (6%), parvovirus (12%), and distemper (13%).

Dr. Haeder explained that in human medicine, concerns about the measles-mumps-rubella vaccine, autism, and the HPV vaccine were all drivers of vaccine hesitancy, and “COVID definitely added fuel to the fire.”

“In my eyes, it increased the intensity of the opposition to vaccines, as well as increased the number of skeptics,” Dr. Haeder said. “We need to start having a well-rounded strategy to address this because as time passes, reversing the inevitable problems, for pets, vets, and humans becomes harder and harder, and we are bound to lose some substantial public health gains we achieve through vaccines.”

Vaccination basics

As veterinary professionals are well aware, the administration of pet vaccines is vital to prevent transmission of disease not only between animals (e.g., distemper, which affects both domestic dogs and foxes, coyotes, wolves, and other wildlife), but between animals and people (e.g., rabies, leptospirosis). Local and state laws intervene when such diseases are life-threatening, as is the case with rabies.

Veterinarians regularly make risk-based assessments when recommending specific vaccination schedules. Local epidemiologic disease trends and applicable local and state disease prevention requirements also impact veterinary considerations. However, clients may not understand all the factors that influence the recommended vaccine schedules and assume they are arbitrary.

Factors veterinarians may consider include:

• Age of the pet
• Exposure to other animals (e.g., pets, wildlife, livestock) and humans, such as through grooming, daycare, boarding, recreational activities, shows or athletic competitions
• Exposure to vectors (e.g., fleas, ticks)
• Environmental exposures (e.g., lakes, ponds)
• Geographic location (e.g., endemic diseases, travel)
• Health status of the individual animal, including any history of prior vaccine reactions and concurrent diseases

The veterinarian and client can then work out what is best for the pet, including consideration of whether a vaccine is considered to be core or non-core, and timing.   

Notably, a rabies antibody titer in a dog or cat may only indicate prior vaccination, not current or future protection. Further, no state recognizes rabies antibody titer results as a substitute for rabies vaccination.

With respect to all vaccines, including core vaccines such as canine distemper, adenovirus, and parvovirus, the AVMA vaccination principles state, “Antibody titers or other immunological measurements to determine if booster vaccination is warranted should not be used if standardized tests and protective levels of immunity have not been defined for the disease.”

When considering the timing of re-vaccination, veterinarians must balance multiple factors including patient disease susceptibility, immune status, and duration of immunity as listed on the vaccine label.

“When pet owners choose not to vaccinate their pets, it does limit the life experiences they can have, including travel, boarding, daycare, grooming, and dog park memberships,” said Dr. Natalie L. Marks, president of MarksDVMConsulting. “For some families, it can even be more severely limiting by restricting certain housing or the ability to register a pet within a municipality.”

Communicating with clients

When communicating with an uncertain client, a veterinarian may find it helpful to first identify the reasons for their hesitancy and acknowledge those concerns. From there, they can educate them about the benefits and risks of vaccination.

According to Dr. Marks, during discussions about vaccination, veterinarians should practice the following three aspects of clinical empathy:

• Understanding the client's perspective, including their emotions, thoughts, beliefs, and circumstances.
• Communicating that understanding back to the client.
• Acting on that understanding in helpful ways for the patient or client.

Developing a comprehensive hospital plan to promote the importance of vaccination is crucial. Dr. Marks uses the “Rule of 7” to ensure that her messaging sticks with clients. This means that a person needs to hear, read, see, or write something at least seven times for it to become a habit.

“As a management team, let's take some time to identify seven touchpoints in the client journey where we can communicate the importance of vaccination with empathy and education,” she explained.

These touchpoints can include adding helpful links to the practice website, creating social media posts on the topic, including the information in email and text confirmations sent to clients before their appointment; discussing it in the exam room; displaying slides on a computer screen; and incorporating it into part of the checkout process.

A version of this story appears in the March 2024 print issue of JAVMA