Lupo Agnese, Coyne Sébastien, Berendonk Thomas Ulrich
Institute of Hydrobiology, Department of Hydrosciences, Technical University Dresden Dresden, Germany.
Front Microbiol. 2012 Jan 26;3:18. doi: 10.3389/fmicb.2012.00018. eCollection 2012.
The environment, and especially freshwater, constitutes a reactor where the evolution and the rise of new resistances occur. In water bodies such as waste water effluents, lakes, and rivers or streams, bacteria from different sources, e.g., urban, industrial, and agricultural waste, probably selected by intensive antibiotic usage, are collected and mixed with environmental species. This may cause two effects on the development of antibiotic resistances: first, the contamination of water by antibiotics or other pollutants lead to the rise of resistances due to selection processes, for instance, of strains over-expressing broad range defensive mechanisms, such as efflux pumps. Second, since environmental species are provided with intrinsic antibiotic resistance mechanisms, the mixture with allochthonous species is likely to cause genetic exchange. In this context, the role of phages and integrons for the spread of resistance mechanisms appears significant. Allochthonous species could acquire new resistances from environmental donors and introduce the newly acquired resistance mechanisms into the clinics. This is illustrated by clinically relevant resistance mechanisms, such as the fluoroquinolones resistance genes qnr. Freshwater appears to play an important role in the emergence and in the spread of antibiotic resistances, highlighting the necessity for strategies of water quality improvement. We assume that further knowledge is needed to better understand the role of the environment as reservoir of antibiotic resistances and to elucidate the link between environmental pollution by anthropogenic pressures and emergence of antibiotic resistances. Only an integrated vision of these two aspects can provide elements to assess the risk of spread of antibiotic resistances via water bodies and suggest, in this context, solutions for this urgent health issue.
环境，尤其是淡水，构成了一个新耐药性不断演变和出现的反应器。在诸如废水排放口、湖泊、河流或溪流等水体中，来自不同来源（如城市、工业和农业废弃物）的细菌，可能因抗生素的大量使用而被筛选出来，并与环境中的菌种汇集混合。这可能对抗生素耐药性的发展产生两种影响：其一，抗生素或其他污染物对水的污染会因选择过程导致耐药性的增加，例如，过度表达广泛防御机制（如外排泵）的菌株的选择。其二，由于环境中的菌种具有内在的抗生素耐药机制，与外来菌种的混合很可能导致基因交换。在这种情况下，噬菌体和整合子在耐药机制传播中的作用显得十分重要。外来菌种可能从环境供体那里获得新的耐药性，并将新获得的耐药机制引入临床。临床上相关的耐药机制，如氟喹诺酮耐药基因qnr，就说明了这一点。淡水似乎在抗生素耐药性的出现和传播中发挥着重要作用，这凸显了改善水质策略的必要性。我们认为，需要进一步了解环境作为抗生素耐药性储存库的作用，并阐明人为压力造成的环境污染与抗生素耐药性出现之间的联系。只有对这两个方面有一个综合的认识，才能为评估通过水体传播抗生素耐药性的风险提供依据，并在此背景下为这个紧迫的健康问题提出解决方案。
