Evaluation of the acquisition and carriage of potentially zoonotic pathogens by hospital visitation dogs in Ontario.

摘要

The work reported in this thesis is the first to characterize the risks of infection inherent to canine animal-assisted interventions (AAIs) in human healthcare facilities (HCFs) in Ontario. A survey of Ontario hospitals in 2004 found that the majority permitted dogs to visit patients. These dogs typically originated from organized AAI programs (79%) and/or from the homes of patients (38%). In a subsequent cross-sectional investigation, 102 active hospital visitation dogs were tested for 18 potentially zoonotic pathogens. Their owners (n=90) were interviewed to collect data on putative risk factors for pathogen carriage, and to characterize the animals and their programs. The most prevalent agent, Clostridium difficile, was detected in 58% of dogs. Other pathogens with zoonotic potential included Giardia spp. in 7 (7%), multi-drug resistant E. coli in 4 (4%) and Toxocara canis and Ancylostoma caninum in 2 (2%) and 1 (1%), respectively. None of the hypothesized risk factors studied was significantly associated with pathogen carriage were identified. Interview responses highlighted great variability in the degree to which animals were screened for participation and in the ways that dogs typically interacted with patients.; In a third investigation, a prospective cohort study, AAI dogs were tested every 2 months for specific healthcare-associated pathogens, and for Salmonella, over a 12-month period, beginning in May, 2005. Data on hypothesized risk factors for pathogen acquisition were collected both prospectively and retrospectively. Exposure to HCFs was a significant risk factor for dogs acquiring methicil lin-resistant Staphylococcus aureus and C. difficile. Among those dogs exposed to HCFs, licking patients, accepting treats, and sitting on beds during visits was associated with pathogen acquisition. Consumption of raw foods of animal origin strongly predicted shedding salmonellae and AmpC beta-lactamase E. coli.; This research culminated in a project designed to develop a comprehensive set of guidelines for AAIs in HCFs, in which 29 stakeholders in AAIs from across North America participated. These guidelines, rather than relying on expensive, intensive testing of dubious effectiveness, emphasize basic, workable practices such as good hand hygiene before and after handling animals in HCFs.