Impact of a Regulation Restricting Critical Antimicrobial Usage on Prevalence of Antimicrobial Resistance in Escherichia coli Isolates From Fecal and Manure Pit Samples on Dairy Farms in Québec, Canada

Abstract

To tackle antimicrobial resistance (AMR), one of the major health threats of this century, the World Health Organization endorsed a global action plan in 2015. This plan calls countries to develop national actions to address AMR. The province of Québec, Canada, adopted a new regulation on the 25th of February 2019, to limit the use in food animals of antimicrobials of very high importance in human medicine. We aimed to establish the impact of this regulation by comparing the AMR situation in dairy cattle in Québec ~2 years before and 2 years after its introduction. As early as 2 years post regulation implementation, we observed a significant decrease in multidrug resistance in the dairy industry in Quebec in the generic E. coli collection, with folate inhibitor and aminoglycoside resistances showing the most significant decrease. No other significant decreases were yet observed.