Anthropogenic contamination sources drive differences in antimicrobial-resistant Escherichia coli in three urban lakes

Antimicrobial resistance (AMR) poses a significant threat to infectious disease treatment, but its prevalence in environmental reservoirs remains unclear. A study isolated antimicrobial-resistant Escherichia coli from three urban waterbodies over a 15-month time series, revealing distinct patterns of resistance. The strains were found to be resistant to clinically important antimicrobials, but susceptible to amikacin and last-line antimicrobials. The resistance was primarily due to acquirable antimicrobial resistance genes, while chromosomal mutations conferred resistance to quinolones. The study also identified a wide array of AMR and virulence genes, and found that environmental persistence, transmission between sites, likely mediated by wild birds, and transfer of mobile genetic elements contributed significantly to the observed patterns.