Artificial plastic substrate for tracking and exploring antimicrobial-resistant bacteria transmission pathways in aquatic ecosystems

Investigating the persistence and dissemination of antibiotic-resistant bacteria (ARBs) in aquatic ecosystems is challenging because conventional methods require large volumes of water, particularly difficult to collect in regions affected by climate-related stress. This study developed and evaluated artificial plastic substrates (APSs) as an effective sampling tool and assessed the potential role of plastic as a transmission vector for ARBs. Five monthly sampling campaigns were conducted at three sites along the Arrone River. A total of 127 ARBs, including extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae and Vibrio spp., were isolated from APSs and raw water (RW) and characterized at the microbiological and molecular levels. APSs recovered more ARBs than RW and captured key antibiotic resistance genes, including class 1 integrons and genes associated with β-lactam, carbapenem, tetracycline, sulfonamide, aminoglycoside, chloramphenicol, and efflux pump-mediated resistance. Overall, APSs proved to be an efficient, cost-effective, reproducible, and minimally invasive tool for monitoring ARBs and ARGs in aquatic ecosystems.