Exploring the contributions of genotypic, phenotypic, social and qualitative data sources to our understanding of antimicrobial resistance in Canada

Antimicrobial resistance (AMR) is a significant global threat to human and veterinary medicine. AMR is a complex health issue, with factors across human and veterinary medicine, plant and animal production, and the economy driving the emergence and persistence of resistance. This thesis sought to incorporate diverse methodological approaches, including data sources, methods of analyses, and types of data, and explore how these data could improve our understanding of AMR and its drivers. The primary objectives were to a) evaluate the use of different data sources to improve understanding of AMR, the drivers of AMR, and the interactions between drivers in the overall system, and b) explore perceptions about AMR, key messages to be communicated, and preferred methods of communication about AMR with future antimicrobial prescribers. The methods used included analysis of surveillance data for extended-spectrum beta-lactamase (ESBL)-producing bacteria, synthesis of literature-derived risk factor data for ESBL-producing Escherichia coli in select food-producing animals, analysis of the AMR system using social network analysis, and qualitative exploration of AMR perceptions among future antimicrobial prescribers. The results suggested that overall prevalence of ESBL-producing E. coli and Salmonella in humans and agrifood samples is low, but that ESBLs are widely distributed in agrifood and human sources. There were few studies examining factors associated with ESBL-producing organisms in food-producing animals, highlighting an important research gap. Analysis of the overall AMR system identified key leverage points, including on-farm antimicrobial use and consumer demand for product, that should be explored as targets for future interventions to reduce AMR. Finally, future antimicrobial prescribers felt that AMR is a very important global issue, and that collaboration between sectors is needed to mitigate AMR successfully. These findings highlight the need for ongoing, integrated surveillance and research efforts across food-producing animals, food products, and humans in Canada, including the drivers of use and resistance, to identify emerging trends and assess the relative contribution of different transmission pathways to resistant human infections. Furthermore, the results have important implications for future knowledge translation and communication materials, and can be used to support the development of communication tools that are tailored to the needs of different stakeholders.