The Veterinarian’s Role in Managing Imported Dogs

Canine Importation Defined

Canine importation is the movement of dogs from one country to another and may occur for many purposes, including resale, adoption, breeding, competition, or travel or relocation with pet owners.¹

How Many Dogs Are Imported?

Little historical information is available on the number of dogs entering Canada and the United States. In 2019, it was conservatively estimated that 37,445 dogs were imported into Canada.² The US Centers for Disease Control and Prevention (CDC) estimates 1.06 million dogs are imported into the United States each year.³

Regulation of Canine Importation

Government bodies (eg, Canadian Food Inspection Agency, CDC, US Department of Agriculture) set requirements for animal importation that may include previous rabies vaccination and/or other vaccinations, a rabies titer test, microchipping, treatment with a parasiticide, isolation, healthy appearance on arrival, and/or examination by a veterinarian in the exporting country.^1,4 Requirements may vary based on patient age, country of origin, and whether the dog is accompanied by an owner.

Few regulations have traditionally existed for dogs imported into Canada and the United States^5-7; however, regulations are becoming more stringent in these countries, particularly in response to rabies concerns. In September 2022, the Canadian Food Inspection Agency banned importation of dogs (except those traveling as personal pets) from countries deemed high-risk for rabies.⁸ The United States enacted a similar ban that expired in August 2024; dogs from countries deemed high-risk for rabies may now be imported with an accompanying vaccine certificate endorsed by an official government veterinarian from the country of origin.⁴ Regulations are available on government websites.^1,4

Challenges With Canine Importation

The potential for spreading pathogens is increased with human and canine travel, and novel and uncommon pathogens have been carried from one country to another by dogs.^5-7,9-15 Recently imported dogs may shed pathogens (with or without accompanying clinical signs) that can be transmitted to the domestic dog population, with highest risk occurring shortly after arrival.^10,15 In some cases, domestic dogs may have little to no protection against novel pathogens.¹⁰ Speculation exists regarding the effectiveness of vaccines in protecting dogs from novel strains of common pathogens (eg, canine distemper virus, canine parvovirus, Leptospira spp),^16-18 but more research is needed. Certain zoonotic pathogens (eg, canine-variant rabies virus, Brucella canis) can also pose a risk to humans.^13,19,20 Numerous rabies-infected dogs with no clinical signs have been imported into Canada and the United States, requiring widespread and costly public health responses for timely postexposure prophylaxis.^13,19,21,22 A recent risk assessment estimated the incidence of rabies in imported dogs was 16 times higher than in domestic dogs in the United States.²³

The welfare of imported dogs is also a significant concern, as dogs may be sourced from illegal breeding operations or transported when too young for travel, when ill or injured, or in overcrowded conditions with limited access to food and/or water for extended periods of time.^5,24-27 Studies have reported transport is stressful for dogs, but research on appropriate transport conditions is limited.²⁸ Stress and conditions of transportation may facilitate pathogen shedding and transmission.⁵ Increased behavior concerns (eg, fear, stress) have also been reported in imported dogs compared with domestic dogs.²⁹

What Is the Veterinarian’s Role in Canine Importation?

Veterinarians play a key role in safe and responsible importation of dogs via advocacy, screening, and education. Those who work with rescue organizations can advocate for management practices that extend beyond minimum requirements. Owners can be educated through raised awareness regarding responsible sourcing of dogs and understanding the importance of seeking veterinary care following importation.

Veterinarians are often the first line of defense against introduction of novel and zoonotic pathogens and should therefore be aware of and screen for infectious pathogens in imported dogs.^2,9,30 Early identification of these pathogens can reduce transmission to domestic dogs and/or caregivers, veterinary staff, and the wider community.

Considerations When Managing Imported Dogs in Clinical Practice

Evidence-based guidelines for the management of imported dogs in veterinary medicine do not exist; however, there are key considerations.

Screening for Recent Importation

Identifying newly imported dogs is necessary for effective management. When scheduling consultations, origins of new patients should be screened to determine whether additional infection control measures will be needed during the appointment. The decision to implement these measures is at the veterinarian’s discretion and should include assessment of the length of time since import, presence of clinical signs, vaccination history, reliability of medical records, and disease risk of the country of origin.⁹

Medical records should also be requested during screening; limited documentation is common.

Thorough Review of Medical Records

Medical records should be examined for vaccination history and schedule, history of treatment with parasiticides, and previous diagnostic test results. Owners may be unaware of a dog’s history, and importation or previous diagnoses with certain diseases may only be identified following review of medical records. Fraudulent medical records can be an issue with imported dogs²⁷; verifying that patient characteristics (eg, age, breed, sex, microchip number) match the medical records provided is thus important. Vaccinations (eg, product administered, administration timing, booster frequency) should comply with local policies. Some studies have shown poor response to rabies vaccination in imported dogs.^15,22,31,32 Poorly formulated vaccines, as well as inappropriate storage, handling, and administration, can reduce vaccine efficacy^33-35; however, the large number of dogs with undetectable rabies antibody titers has raised concern that many imported dogs were not vaccinated, despite having an accompanying rabies-vaccine certificate.^15,22,31,32

Revaccination should be considered if paperwork is not available, is illegible, cannot be translated, indicates incomplete or inappropriate courses of vaccines, or does not match the dog. From 2018 to 2020, an increased number of dogs (52%) were denied entry into the United States, mainly because of falsified rabies vaccine certificates.³⁶

Infection Control Protocols

Transmission of pathogens from imported dogs has occurred at veterinary clinics.¹⁰ For example, in Ontario, Canada, a local dog that contracted canine influenza from an imported dog subsequently spread the virus to other dogs at a veterinary clinic.¹⁰ Strong infection control protocols for imported dogs can help prevent spread of disease. Recommendations include limiting a dog’s movement within the clinic; limiting contact with other animals in the clinic; limiting contact with staff; using personal protective equipment (eg, gowns, gloves), especially if the dog is presented with skin lesions; and conducting proper cleaning and disinfection of the examination room and equipment after the appointment.

Pathogen Testing

No pathogen testing requirements exist for dogs imported into Canada or the United States.^1,4 Testing is warranted for dogs with clinical signs of illness. Screening may also be needed for apparently healthy dogs with high-risk circumstances (eg, unknown origin, intact neuter status, incomplete or nonexistent medical history, arrival with a large group of dogs, previous stray, illegal breeding facility origin) or from countries endemic for certain pathogens.^5,9,15

Pathogens carried by imported dogs may be novel, not routinely tested for in domestic dogs, and/or unfamiliar to veterinarians outside the origin country.⁵ Little information is available to guide appropriate diagnostic testing in imported dogs. Resources on pathogen endemicity by region include the Canine Disease Map and the CDC website (see Resources).^37,38 Commonly reported pathogens (including Dirofilaria immitis, Ehrlichia canis, and intestinal parasites) in imported dogs can provide insights into screening.^5,9 Additional pathogens commonly diagnosed in imported dogs include Leishmania spp, canine influenza virus, canine parvovirus, and canine distemper virus.^5,7,9 B canis, rabies virus, and Echinococcus multilocularis are less commonly reported but are of concern due to their zoonotic potential.^5,7Some pathogens have long incubation periods (eg, Leishmania spp, D immitis) or may be shed intermittently (eg, B canis) and may require follow-up testing, even if tested for prior to importation.^5,12 Dogs should also be examined thoroughly for external parasites.

Owners with dogs from areas considered high-risk for rabies should be advised that clinical signs of infection may not be seen for up to 6 months (longer in rare cases).^13,19,22 Rabies vaccination prior to importation does not prevent rabies in dogs already incubating the infection.⁶

Behavior Assessment

Behavior issues should be screened for and support offered, if appropriate, including an extended behavior assessment and/or referral to a veterinary behaviorist or certified trainer. Many imported dogs have been adopted into novel environments (eg, a feral street dog adopted into a suburban home) and require support in adapting to new surroundings.^29,39

Isolation

Only dogs with clinical signs of illness or failure to meet importation requirements may be isolated at preapproved or registered facilities on arrival to Canada or the United States.^1,4 Not all infected dogs develop clinical signs of disease by the time of arrival. Newly imported dogs should therefore have limited contact with other animals for a minimum of 7 to 14 days to allow observation for clinical signs and prevention of transmission of some potential pathogens, notably respiratory pathogens^9,40; however, this timeframe may not encompass all pathogens (eg, canine distemper virus, rabies virus, Leishmania spp).⁹ Dogs with questionable vaccination status should avoid contact with other animals until vaccinations are verified or updated.

Owner Education

Owners should be encouraged to bring imported dogs to the clinic shortly after arrival so vaccination history and health status can be verified and owners can be made aware of possible zoonotic pathogens, including B canis, rabies, enteric pathogens, and intestinal parasites.^5,7

Education is also key for owners seeking ethical sourcing of imported dogs; a website like Questions to Ask Before Buying Or Adopting A Dog (see Resources) can be provided. Importation can relieve the immediate suffering of an individual animal but is not a sustainable solution for improving animal welfare.⁹