This report examines 26 therapy dog/handler pairs in southern Ontario, Canada.Dogs visited both acute-care (n = 12) and longterm– care (n = 14) facilities from June to August 2007. Canine forepaws, hair coats, and handler hands were cultured for methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, and Clostridium difficile before and after each clinic visit. Participants completed a form to assess interactions between dogs and patients and report hand-sanitizing techniques. MRSA strains were characterized by pulsed-field gel electrophoresis. Polymerase chain reaction was performed for ribotyping and gene detection of C difficile strains.No pathogens were detected before visitation. Vancomycin-resistant enterococci were not detected before or after visitation.A dog visiting an acute-care facility harbored an epidemic C difficile strain on its paws after the visit.A known hospitalacquired MRSA strain was detected on the hands of a study investigator after she petted a dog that had visited another facility. Handlers did not harbor any pathogens before or after visitation despite the fact that only 50% practiced hand-hygiene techniques. Dogs included in this study freely roamed hospital corridors, had direct contact with patients, and occasionally sat on patient beds.This report revealed evidence of therapy dog colonization with hospital-acquired pathogens and the potential for transient MRSA colonization from dog to human.

COMMENTARY: The tremendous emotional benefits for patients of pet therapy programs are well known.However, such programs are risky because of the potential for pathogen transfer.This study emphasizes the necessity and benefits of vigilant hand hygiene for handlers, hospital staff, and patients during interactions with therapy dogs to prevent pathogen transfer.—Indu Mani, DVM, DSc (infectious disease)

Contamination of pet therapy dogs with MRSA and Clostridium difficile. Lefebvre SL, Weese JS. J HOSP INFECT doi:10.1016/j.jhin.2009.02.019.