Hydrodynamics Shape Antibiotic Resistance in Wastewater-Impacted River Biofilms

This study shows that water flow conditions strongly influence the spread and persistence of antimicrobial resistance genes (ARGs) in aquatic environments impacted by wastewater. Using river biofilms in controlled flume systems, researchers found that dynamic, flowing water supports higher microbial diversity and maintains or even increases ARG abundance over time, whereas static water conditions lead to lower diversity and a gradual loss of ARGs. Key resistance genes and mobile genetic elements persisted more in flowing systems, highlighting hydrodynamics as a critical factor in ARG dissemination. These findings underscore the importance of considering water flow in wastewater management and One Health strategies to limit environmental AMR spread.