Resistome prevalence and diversity in Escherichia coli isolates of global wastewaters

Abstract

Abstract Antimicrobial resistance (AMR) is a global problem driven by unregulated antibiotic use leading to the emergence of resistant strains; the “antibiotic paradox” where the cure is the cause of deadlier infections. AMR is fueled by wastewater mismanagement and global mobility, leading to the dissemination of AMRs and multidrug-resistant (MDR) strains worldwide. We embarked on estimating the ‘invasion’ of antibiotic-resistant genes (ARGs) into the normal flora of humans. We screened 300 local wastewater E. coli and sequenced eight isolates to study the genome diversity and resistome, which were then compared with the 529 globally isolated wastewater E. coli (genomes from the PATRIC database). Local wastewaters had 26% resistant and 59% plasmid-bearing E. coli. Global wastewater resistome majorly comprised ARGs against beta-lactam, aminoglycosides, fluoroquinolone, sulfonamide, and trimethoprim. Resistance to colistin, a last-resort antibiotic, was prevalent in MDRs of European and South Asian isolates. Canada fared better in all the AMR parameters, likely due to effective AMR surveillance, antibiotic stewardship and wastewater disinfection, which could serve as a model for other regions. A systems approach is required to address the AMR crisis on a global scale, reduce antibiotic usage and increase the efficiency of wastewater management and disinfection.