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Hand washing best way to avoid zoonotic organisms
BY RACHELLE COOPER
Eighty per cent of therapy dogs are carrying zoonotic diseases that can potentially pass from animals to people, say OVC researchers. In a study published in the Journal of Hospital Infection, they found 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's no published evidence of people catching an agent from a therapy dog, says Sandra Lefebvre, a veterinarian who is a PhD candidate in the Department of Population Medicine.
“The potential is there, but we don't yet know if it happens,” she says.
It would depend on a lot of factors such as the immune status of the people interacting with the dogs, whether they have an open wound or whether they put their hand in their mouth after handling the dog, she says.
“The aim of this research was to collect scientific evidence showing that there needs to be more stringent evidence-based protocols for therapy dogs.”
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 says.
Lefebvre, along with Profs. David Waltner-Toews, Population Medicine, and Scott Weese, 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. Although the risk of this strain to people is unclear, it raises concerns, says Weese. He, 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. 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,” says Lefebvre.
Dogs can also pick up bacterial strains that originate in hospitals and transfer them to people in the community on a day-to-day basis, she says.
Hand washing before and after handling dogs is probably the best way to avoid contacting a zoonotic organism, says Lefebvre, who notes that hand sanitizers are readily available in hospitals and nursing homes. Dogs can't take such precautions, so it's up to people to do so, she says.
Placing a sheet on a patient's bed or lap to protect the person from direct contact with the dog is also a good way to protect both patients and dogs, she says.
What's just as likely as a dog transmitting a disease to a patient is a dog carrying bacteria from one patient to another, says 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 closer contact with patients than other visitors do — some lick patients' faces and jump up on their beds — strict regulations around therapy dogs make a lot of sense, she says.
Until more research is done, ensuring that pet-visiting programs continue to spread benefits instead of germs comes down to common sense, says Lefebvre.
“All participants, whether they're health-care 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.”
