U of G Researchers Find Prevalence of Disease in Therapy Dogs

May 09, 2006 - News Release

Researchers at the University of Guelph’s Ontario Veterinary College have found that 80 per cent of therapy dogs are carrying zoonotic diseases that can potentially pass from animals to people. Their research, published in the Journal of Hospital Infection, shows several health risks associated with dogs visiting hospitals and nursing homes to boost spirits and improve health.

Although it’s now established that most dogs are carrying something, there is no published evidence of people catching an agent from a therapy dog, said Sandra Lefebvre, a veterinarian who is a U of G PhD candidate in population medicine. “The potential is there, but we don’t yet know if it happens,” she said. “It would depend on a lot of factors like the immune status of the people interacting with the dogs, if they have an open wound, or if they put their hand in their mouth after handling the dog.”

“The aim of this research was to collect scientific evidence showing that there needs to be more stringent evidence-based protocols for therapy dogs,” said Lefebvre. Existing therapy dog protocols dictated by Canadian hospitals and the Centres for Disease Control and Prevention — such as keeping animals parasite-free, clean and well-groomed, and maintaining up-to-date vaccinations — are only recommendations and don’t address many important concerns, she said.

Lefebvre, along with Prof. David Waltner-Toews from the Department of Population Medicine and Prof. Scott Weese, Department of Clinical Studies, examined 102 visitation dogs from across Ontario for 18 specific pathogens.

A surprising 58 per cent of the dogs were carrying the Clostridium difficile bacterial strain. While the risk of this strain to people is unclear, it raises concerns, said Weese. He, along with Lefebvre and Waltner-Toews, highlighted these concerns in another recent report that focused on a poodle visitation dog that carried the C. difficile strain responsible for serious outbreaks of disease in people, particularly in Quebec. Other infections from pathogens detected in the dogs were Salmonella, multidrug-resistant E. coli and Pasteurella spp.

“The problem lies in the fact that dogs can carry disease-causing germs and still look healthy,” said Lefebvre. Dogs can also pick up bacterial strains that originate in hospitals and transfer them to the people in the community on a day-to-day basis, she said.

Hand washing before and after handling dogs is probably the best way to avoid contacting a zoonotic organism, said Lefebvre. “Hand sanitizers are readily available in hospitals and nursing homes and since dogs can’t do anything, it just makes sense that people should take extra precautions.” Placing a sheet on the patient’s bed or lap to protect them from direct contact with the dog is also a good way to protect both patients and dogs, she said.

What’s just as likely as a dog transmitting a disease to a patient is a dog carrying bacteria from one patient to another, said Lefebvre. “If there’s any indication that a patient is infectious, that patient shouldn’t visit with a therapy dog to protect the people who handle the dogs afterwards, and to protect the dog itself.”

Because dogs have much more intimate contact with patients than other visitors – some lick patients’ faces and jump up on their beds – strict regulations around therapy dogs make a lot of sense, she said.

Until more research is done, ensuring that pet visiting programs continue to spread benefits instead germs comes down to common sense, said Lefebvre. “All participants, whether they’re healthcare personnel, patients or visitation dog owners, need to start thinking seriously about making infection control an integral part of their interactions to preserve the popularity of pet-visiting programs.”

Contact:
Sandra Lefebvre
(519) 824-4120, Ext. 54873 / slefebvr@uoguelph.ca

University of Guelph
50 Stone Road East
Guelph, Ontario, N1G 2W1
Canada
519-824-4120