Antimicrobial resistance in natural and anthropogenic environments

dissemination, risks, and integrated surveillance

Abstract

Objective: to compile and interpret evidence on antimicrobial resistance (AMR) in natural and anthropogenic environments, discussing its dissemination,
health risks, and implications for integrated surveillance (One Health). Methods: an integrative literature review of articles indexed in PubMed, ScienceDirect, and the Virtual Health Library, collected from 2016 to 2024. Studies were selected using predefined inclusion/exclusion criteria, as well as the descriptors “MDR genes,” “antibiotics,” and “environment.” Results: this study identified 83 articles, of which 65 were excluded for not meeting the inclusion criteria, resulting in 18 articles that composed the review. These studies demonstrated that diverse resistomes occur not only in urban areas but also in remote ecosystems, suggesting a natural and ancient component of antimicrobial resistance (AMR). In human-impacted settings, surface waters near urban centers concentrate multidrug-resistant E. coli and antimicrobial resistance genes (ARGs), often associated with biofilms. Wastewater treatment plants (WWTPs) reduce bacterial loads yet release residual ARGs, sustaining resistance flow. In agriculture, water reuse and animal waste introduce ARGs into soil and food, while heavy metals and biocides act as co-selectors, and bacteriophages facilitate horizontal gene transfer. Conclusion: AMR is multifactorial and environmentally widespread, demanding continuous integrated surveillance, more effective treatment technologies, rational antibiotic use, and regulation
of water reuse—all indispensable pillars of the One Health approach.