Washington - The British Veterinary Association felt compelled to hop onto Twitter to issue a notable statement: "There's currently no reliable scientific evidence to indicate autism in dogs (or its link to vaccines)," the group wrote.
The tweet came in response to a widely condemned call-out from the television show Good Morning Britain for interviews with pet owners who believe their dogs developed "canine autism" as a result of vaccines or who refuse routine shots over worries about side effects.
But the association also suggested its response had roots across the Atlantic: "We are aware of an increase in anti-vaccination pet owners in the US," it said, "who have voiced concerns that vaccinations may lead to their dogs developing autism-like behavior."
John de Jong, a Boston-area veterinarian and incoming president of the American Veterinary Medical Association, said his organisation firmly agrees with its British counterpart: There's no evidence for autism in dogs or any link to vaccines - a theory that has been thoroughly discredited in humans. But he also said he has never been asked by a client about this notion, nor does he know of other veterinarians who have.
Heather Loenser, a senior veterinary officer with the American Animal Hospital Association, echoed that.
"I have never had a client voice that concern," Loenser, who practices in New Jersey, wrote in an email, adding that she has only "seen it pop up on social media from time to time."
No one tracks pet vaccination rates. That said, both Loenser and de Jong said they've seen small increases in clients who question the necessity or frequency of pet vaccinations. De Jong said some are influenced by breeders who tell buyers to wait on shots until after a dog has produced litters, while others express a vaguer skepticism about possible side effects.
More generally, he said, the doubts are reflective of a pet "humanization" trend that has driven a surge in organic and grain-free pet food sales, expensive and invasive end-of-life care, and doggy fitness centers.
"It's fair to say that a lot of what we see in veterinary medicine seems to follow the curve of what's popular in human medicine," de Jong said. "The human-animal bond is at an all time high, and people consider their pets as extended members of the family."
Other "core" vaccines, including those for distemper and parvovirus in dogs, are strongly recommended. They have been highly effective, veterinarians point out. Rabies has been eradicated in domestic canines, and distemper is extremely rare. De Jong said he treated dogs with parvovirus as a veterinary student in the early 1980s but now seldom sees it.
"If you take a look at the general health and longevity of both animals and people in society today, we have longer and healthier lives due to preventive medications, preventive health care, good diets and vaccines," he said.
Vaccines can have minor side effects like swelling and very rarely more serious ones. And although pets typically are offered a series of immunizations, pet owners can discuss with their veterinarians which ones, other than rabies, are critical. A cat living in a high-rise condo, for example, might not need a vaccine for leukemia, de Jong said.
While de Jong said the veterinary association has detected no major cause for alarm about anti-vaxx-driven outbreaks in pets, he emphasized how much he hopes the idea doesn't spread. Many diseases against which pets are immunized, such as rabies, can infect both animals and people.
"Widespread use of vaccines has prevented death and disease in millions and millions of animals," he said. "The benefits far outweigh the risks, by a mile."