Tskhay Faina, Köbsch Christoph, Elena Alan X, Bengtsson-Palme Johan, Berendonk Thomas U, Klümper Uli
Institute of Hydrobiology, Technische Universität Dresden, Zellescher Weg 40, Dresden, Germany.
Division of Systems and Synthetic Biology, Department of Life Sciences, SciLifeLab, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
One Health. 2025 Apr 1;20:101026. doi: 10.1016/j.onehlt.2025.101026. eCollection 2025 Jun.
Effective surveillance of antimicrobial resistance (AMR) in the environment is crucial for assessing the human and animal health risk of AMR pollution. Wastewater treatment plants (WWTPs) are one of the main sources of AMR pollutants discharged into water bodies. One important factor for assessing the risks associated with such pollution is the colonization potential of the resistant bacteria (ARB) and resistance genes (ARGs) from the environment into human or animal microbiomes upon exposure. This study explores whether fish can act as sentinels for surveillance of AMR pollution in general and specifically the human colonization potential of ARB in rivers impacted by WWTP effluents. Two riverine fish species, Brown trout, and European bullhead, were sampled up- and downstream a German WWTP. The two fish species were chosen due to their different lifestyles: Trout are mainly actively swimming in the water phase, while bullheads are sedentary and river sediment-associated. The bacterial microbiomes and resistomes of fish gills, skin, and feces were compared with those of the respective river water and sediment up- and downstream of the WWTP. Microbiomes of both fish mirrored the changes in river water and sediment downstream of the WWTP, with significant shifts in bacterial community composition, particularly an increase in Proteobacteria and Verrucomicrobia. However, increases in ARG abundances observed in water and sediment downstream of the WWTP were not reflected in any of the fish-associated resistomes. This indicates that while the fish microbiome is sensitive to environmental changes, resistomes of poikilothermic animals such as fish are less responsive to colonization by ARB originating from WWTPs and may not serve as effective sentinels for assessing AMR pollution and colonization risks in freshwater environments. This study highlights the complexity of using wildlife as indicators for environmental AMR pollution and suggests that other species are better suited for surveillance efforts.
有效监测环境中的抗菌药物耐药性（AMR）对于评估AMR污染对人类和动物健康的风险至关重要。污水处理厂（WWTPs）是排放到水体中的AMR污染物的主要来源之一。评估此类污染相关风险的一个重要因素是抗性细菌（ARB）和抗性基因（ARGs）在接触后从环境定殖到人类或动物微生物群的潜力。本研究探讨了鱼类是否可以作为监测AMR污染的哨兵，特别是受污水处理厂废水影响的河流中ARB的人类定殖潜力。在德国一家污水处理厂的上下游采集了两种河鱼，褐鳟和欧洲杜父鱼。选择这两种鱼类是因为它们的生活方式不同：鳟鱼主要在水相中活跃游动，而杜父鱼是定居性的，与河流沉积物相关。将鱼鳃、皮肤和粪便的细菌微生物群和耐药基因组与污水处理厂上下游相应的河水和沉积物进行了比较。两种鱼的微生物群都反映了污水处理厂下游河水和沉积物的变化，细菌群落组成发生了显著变化，特别是变形菌门和疣微菌门的增加。然而，在污水处理厂下游的水和沉积物中观察到的ARG丰度增加并未在任何与鱼相关的耐药基因组中体现出来。这表明，虽然鱼类微生物群对环境变化敏感，但鱼类等变温动物的耐药基因组对源自污水处理厂的ARB定殖反应较小，可能无法作为评估淡水环境中AMR污染和定殖风险的有效哨兵。本研究强调了将野生动物用作环境AMR污染指标的复杂性，并表明其他物种更适合用于监测工作。
