Enhancing surveillance of antimicrobial resistant organisms in British Columbia through community-level wastewater testing

Antimicrobial resistance (AMR) is a global health challenge, with carbapenemase-producing organisms (CPOs) posing a significant concern in British Columbia, Canada. Traditional surveillance focuses on hospital-associated data, overlooking community-level trends. Monitoring carbapenemase genes in communities can provide early insights into resistance trends and support antimicrobial stewardship efforts. This study employs wastewater surveillance to track antimicrobial resistance genes (ARGs) at the community level. Four ARGs, bla_NDM, bla_KPC, bla_OXA-48, and mcr-1, were detected and quantified in wastewater samples from five treatment plants across British Columbia. The results revealed year-round ARG presence in wastewater, with bla_OXA-48 being the most prevalent, followed by bla_NDM, bla_KPC, and mcr-1. Seasonal fluctuations were observed, with most ARGs peaking in the winter and spring, a trend not reflected in clinical data. Notably, mcr-1 was detected in wastewater despite its limited clinical presence. These results highlight the value of integrating wastewater surveillance with traditional methods to enhance AMR monitoring.