MULTIDRUG-RESISTANT BACTERIAL COLONIZATION PATTERNS IN COMMUNITY WASTEWATER AND THEIR PUBLIC HEALTH IMPLICATIONS: A NARRATIVE REVIEW

Abstract

Background: The proliferation of multidrug-resistant (MDR) bacteria poses a critical threat to global public health. Community wastewater is increasingly recognized not merely as a reflection of community-level antimicrobial resistance (AMR) but as a dynamic environment that actively amplifies and disseminates resistance genes and pathogens, creating significant exposure risks for human populations.

Objective: This narrative review aims to synthesize current evidence on the patterns of MDR bacterial colonization in community wastewater systems and to critically analyze the subsequent implications for public health.

Main Discussion Points: The review delineates the wastewater resistome as a rich repository of diverse antibiotic resistance genes, often associated with mobile genetic elements. It confirms the persistent detection of clinically significant MDR bacteria, including carbapenem-resistant Enterobacterales and methicillin-resistant Staphylococcus aureus, throughout wastewater treatment processes, which are shown to be inadequate for their complete removal. The discussion further explores the role of treated effluent and biosolids as critical pathways for environmental contamination and community exposure. The application of wastewater-based epidemiology (WBE) is highlighted as a promising tool for population-level AMR surveillance. However, the literature is marked by methodological limitations, including a lack of standardization and longitudinal studies, which challenge the precise quantification of direct health risks.

Conclusion: Evidence conclusively identifies wastewater as a significant reservoir and conduit for AMR. To mitigate this threat, there is an urgent need to integrate WBE into public health surveillance and to update water quality guidelines to include AMR parameters. Future research must prioritize standardized, longitudinal, and intervention-based studies to better quantify transmission risks and evaluate the efficacy of mitigation strategies.