antibiotic resistance patterns of escherichia coli isolated from drinking water sources: implications for public health and surveillance strategies

The growing prevalence of antimicrobial resistance (amr) is a critical public health concern, particularly as it relates to environmental transmission routes such as contaminated drinking water. escherichia coli (e. coli), a common inhabitant of the intestinal tracts of humans and animals, is widely used as a biological indicator of fecal contamination in water systems. however, beyond indicating sanitary lapses, e. coli increasingly serves as a reservoir and vector of antibiotic resistance genes, many of which are capable of horizontal transfer to other pathogens via mobile genetic elements such as plasmids, integrons, and transposons. this comprehensive review examines the occurrence, resistance profiles, and genetic mechanisms of antibiotic-resistant e. coli isolated from drinking water sources across diverse geographical regions. evidence from global surveillance, particularly in low- and middle-income countries (lmics), reveals high contamination rates in untreated water sources, wells, surface water, and even municipal supplies. recent studies report a pooled e. coli prevalence exceeding 37% in drinking water samples globally, with over 40% of isolates classified as multidrug-resistant (mdr). frequently detected resistance determinants include blatem, blactx-m, and genes conferring resistance to quinolones, aminoglycosides, and tetracyclines—highlighting critical overlaps between clinical and environmental resistomes. resistance patterns vary significantly by region and season, influenced by local sanitation infrastructure, anthropogenic activities, and environmental conditions. advanced surveillance approaches such as antimicrobial susceptibility testing (ast), polymerase chain reaction (pcr), and whole genome sequencing (wgs) have been instrumental in tracking resistance dynamics and transmission potential in waterborne e. coli populations. the public health implications are profound, including treatment failure rates of 25-40% for mdr infections, increased healthcare costs, and elevated mortality risks, particularly among vulnerable populations. this review emphasizes the urgent need for integrated water quality monitoring, expanded participation in global amr surveillance initiatives such as the who's global antimicrobial resistance and use surveillance system (glass), and strengthened local sanitation and water infrastructure. community-level interventions and international collaboration are essential to contain the environmental spread of antibiotic-resistant e. coli and mitigate its escalating impact on human health.