A controversial American government decision to impose new requirements on dogs entering the U.S. was prompted by a "dramatic increase" in falsified documents and fraud — including cases of people using Canada to bring dogs from countries with high rates of rabies into the U.S.

A lengthy notice from the U.S. Centers for Disease Control and Prevention (CDC) and the Department of Health and Human Services (HHS) — obtained by CBC News — sheds new light on a decision that took the Canadian government, Canadian veterinarians, dog owners and federal Health Minister Mark Holland by surprise in May.

The notice also raises questions about whether Canadian officials are doing enough to prevent dogs from countries where rabies is rampant from entering Canada.

Dr. Tim Arthur, president of the Canadian Veterinary Medical Association, said the problems the U.S. is trying to address with new rules could also affect Canada.

"I think it would be very helpful for Canada to tighten up our border about dogs coming in from countries that have canine variant rabies," he said.

The Canadian Food Inspection Agency says it introduced new measures in 2022 to prohibit the commercial importation of dogs from countries with high levels of rabies into Canada. It says it "continues to explore options to further strengthen Canada's import requirements for dogs."

The controversy centres on new requirements that went into effect on Aug. 1 for anyone bringing their dogs with them to the U.S., and for Americans returning to the U.S. with their dogs.

Following negotiations between Canada and the U.S. and a trip by Holland to Washington, the U.S. agreed to a nine-month grace period for countries like Canada with low rates of rabies. Dogs covered by the grace period will have to be at least six months old and microchipped, and will have to have spent the previous six months in a low-rabies country; their owners also will have to fill out a form. The CDC has simplified other requirements during the grace period.

New rules planned for at least a year

The notice published on a U.S. government website on May 13 reveals that the new rules have been in the works for at least a year, with a consultation period that resulted in 2,106 comments — including one comment from animal rescue groups with 118,312 signatures.

In its notice, the CDC says the risk of rabies being re-introduced into the U.S. has been rising, fuelled in large part by dogs being imported from other countries for profit and by international animal rescue organizations.

The agency says it has also seen a "dramatic increase" in people falsifying the paperwork that has accompanied some of those dogs.

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Health Minister Mark Holland says that ensuring your dogs have up-to-date vaccinations is a 'good idea.' Holland added that ‘mistakes get made’ but in a short period of time, the Canadian government worked with the American administration to make sure Canadians were treated fairly.

"In 2020, CDC observed a 52-per cent increase in the number of dogs that were ineligible for admission due to falsified or fraudulent documentation as compared to 2018 and 2019," the CDC notice says.

The CDC says some people also claim dogs are theirs when they aren't.

"CDC has documented numerous importations every year in which flight parents transport dogs for the purpose of resale, adoption, or transfer of ownership that do not meet CDC's entry requirement," the agency wrote.

"These flight parents often claim the dogs are their personal pets to avoid U.S. Department of Agriculture (USDA) Animal Care entry requirements and potential tariffs or fees under CBP regulations. Even when well-meaning, these importers jeopardize public health, as many of them do not know the history of the animals they are transporting."

The notice says that in some cases, importers have been turning to Canada in their efforts to get dogs from countries with high levels of dog-maintained rabies virus variant (DMRVV) into the U.S.

"HHS/CDC has documented many instances of young dogs under six months of age being routed from DMRVV high-risk countries through DMRVV-free countries, such as Canada or Mexico, to circumvent U.S. entry requirements," says the notice.

The notice details four cases since 2015 of dogs with rabies brought into the U.S. by animal rescue groups — three from Egypt and one from Azerbaijan. An investigation revealed the documents for the dogs imported from Egypt had been falsified.

The notice says two rabid dogs were imported from Iran to Canada in July 2021 and January 2022, pointing out that it occurred at the same time as the U.S. had imposed a temporary suspension on the importation of dogs from countries with high rates of rabies.

The criminal dog trade

The notice also cites a Canadian study conducted between 2021 and 2022 which found that, when tested, nearly half of the rescue dogs with current rabies vaccination certificates brought into Canada had no detectable rabies titer to indicate they had actually been vaccinated.

The notice says it's not just international animal rescue groups bringing dogs into the U.S.

"There is growing evidence that criminal networks are becoming involved in the lucrative dog trade, and the illegal puppy trade was reported to have increased during the pandemic," the CDC wrote.

When a dog with rabies is detected, the CDC estimates it costs $270,000 on average to investigate and vaccinate humans exposed to the dog.

While human deaths from rabies in the U.S. are rare and generally follow exposure to wild animals, the CDC estimates 59,000 people die around the world each year from rabies, many of them children.

The CDC admits it doesn't really know how exactly many dogs enter the U.S. from other countries but estimates a million dogs are brought into the country each year, 100,000 of them from countries with high levels of rabies.

The CDC's notice also provides explanations for some of the measures it has introduced, such as the requirement that dogs be microchipped.

"CDC has documented several instances of importers attempting to present records of vaccinated dogs as the vaccination records for dogs that lacked appropriate veterinary paperwork in an attempt to import the unvaccinated dogs into the United States without detection," the agency says.

"Because microchips were not required for entry into the United States at that time and the dogs in question were not microchipped, the public health investigations to confirm the identity of those dogs were both resource-intensive and challenging."

Vaccine skepticism

The notice says the new rules are also necessary because of gaps in rabies vaccinations among U.S. dogs.

"Researchers recently documented canine vaccine hesitancy, which is defined as 'a dog owners' skepticism about the safety and efficacy of administering routine vaccinations to their dogs,' in 53 per cent of the U.S. population," it says.

Arthur said his members were taken by surprise by the CDC announcement and feel like they have been left out of the loop. As talks between Canada and the U.S. continue, his group is recommending that veterinarians from both Canada and the United States be at the table.

Arthur recommends Canada tighten its own rules as well. He said importing dogs from abroad has become very lucrative and while commercial importation of dogs has been prohibited, a private citizen could bring a dog from a country with high levels of rabies into Canada.

And there is no limit on the number of dogs someone can bring in, he pointed out.

"I don't see any hard and fast rules on CFIA about you as a private citizen owning one dog, two dogs, five dogs," said Arthur. "All you have to do is say 'They're my dogs.' So, you can bring them into Canada and turn around and sell them the next day. Nobody would know any different."