摘要

       抗生素耐药性的发展及其决定因素的传播是一个新兴的公共卫生问题，因为它损害了直到最近才可以治疗的感染的治疗选择。对万古霉素抗性肠球菌 (VRE) 暴发的调查表明，环境是抗生素抗性基因 (ARG) 的重要储存库。然而，关于南非水源中存在 ARG 的数据很少。在这项研究中，对从废水处理厂 (WWTP)、地表水和医院污水收集的水样进行了筛选，其中含有对四类抗生素具有抗性的基因的肠球菌。在污水处理厂和医院污水的原始进水和处理过的废水排放中检测到含有 ARG 的肠球菌分离株。质粒和转座子编码的 ermB（大环内酯）、tetM 和 tetL（四环素）以及 aph(3')-IIIa（氨基糖苷类）基因在分离株中经常被检测到，尤其是在粪肠球菌中。处理过的废水中含有携带 ARG 的肠球菌表明 ARG 被排放到环境中，在那里它们的增殖可能会持续下去。从废水中回收的肠球菌克隆复合体 (CC) 中包括粪肠球菌 CC17 (ST18)，它经常与医院爆发有关，以及一种新型粪肠球菌序列类型 (ST)，ST780。

       The development of antibiotic resistance and dissemination of its determinants is an emerging public health problem as it compromises treatment options of infections that were, until recently, treatable. Investigation of outbreaks of vancomycin resistant enterococci (VRE) suggests that the environment serves as a significant reservoir for antibiotic resistance genes (ARGs). However, there is a paucity of data regarding the presence of ARGs in the water sources in South Africa. In this study, water samples collected from wastewater treatment plants (WWTPs), surface water and hospital sewage were screened for enterococci harbouring genes conferring resistance to four classes of antibiotics. Enterococci isolates harbouring ARGs were detected in raw influent and treated wastewater discharge from WWTPs and hospital sewage water. Plasmid and transposon encoded ermB (macrolide), tetM and tetL (tetracycline) as well as aph(3’)-IIIa (aminoglycosides) genes were frequently detected among the isolates, especially in E. faecalis. The presence of enterococci harbouring ARGs in the treated wastewater suggest that ARGs are discharged into the environment where their proliferation could be perpetuated. Among the enterococci clonal complexes (CCs) recovered from wastewater were E. faecium CC17 (ST18), which is frequently associated with hospital outbreaks and a novel E. faecalis sequence type (ST), ST780.

https://www.sciencedirect.com/science/article/abs/pii/S0269749118333025