Abstract:
OBJECTIVE: The emergence and spread of carbapenemase-producing organisms (CPOs) represent a global health threat because they are associated with limited treatment options and poor clinical outcomes. Wastewater is considered a hotspot for the evolution and dissemination of antimicrobial resistance. Thus, analyses of municipal wastewater are critical for understanding the circulation of these CPOs and carbapenemase genes in local communities, which remains scarcely known in Japan. This study resulted in several key observations: (i) the vast majority of bla GES genes, including six new bla GES variants, and less frequent bla IMP genes were carbapenemase genes encountered exclusively in wastewater influent; (ii) the most dominant CPO species were Aeromonas spp., in which a remarkable diversity of new sequence types was observed; and (iii) CPOs were detected from combined sewer wastewater, but not from separate sewer wastewater, suggesting that the load of CPOs from unrecognized environmental sources could greatly contribute to their detection in influent wastewater.
摘要:
我们对市政废水中检测到的产碳青霉烯酶生物(CPO)进行了表征,以更好地了解社区中CPO的流行病学。总的来说,从2020年12月到2021年10月,每隔一个月在六个采样点收集36个样本。未从接收分离的下水道管线的进口A的进水中回收CPO,处理过的废水,以及污水出口上游和下游的河水样本。相比之下,在从入口B和C采集的所有进水样品中检测到75种CPO,这些入口接收收集生活/工业废水和雨水径流的联合下水道。优势种(25/75,33.3%),和其他11个气单胞菌属。总共占CPO的48%。其余39株肠杆菌主要包括17种克雷伯菌。和10个Raoultellaspp。携带blaGES碳青霉烯酶基因的CPO占主导地位,占75个分离株中的72个,包括两个同时携带blaGES-24和blaIMP-1的分离株(96%),其次是三个blaimp阳性分离株,这些碳青霉烯酶基因主要在不同的1类整合子中携带。在blaGES变体中,包括六个新变种(blaGES-47,blaGES-48,blaGES-49,blaGES-50,blaGES-51和blaGES-54),在28个CPO中检测到blaGES-5,气单胞菌属。占这些生物的53.6%。定量分析显示,从入口B和C重复检测到blaGES-48阳性的A.caviaeST1056,该细菌克隆的总数在废水进水中最高。总之,我们的研究表明,从连接到联合下水道系统的进水入口中分离出的CPO中,各种blaGES碳青霉烯酶基因的患病率和持久性很高。重要因素碳青霉烯酶产生生物(CPO)的出现和传播代表了全球健康威胁,因为它们与有限的治疗选择和不良的临床结果有关。废水被认为是抗生素耐药性演变和传播的热点。因此,对城市废水的分析对于了解这些CPOs和碳青霉烯酶基因在当地社区的循环至关重要,这在日本还鲜为人知。这项研究得出了几个关键的观察结果:(i)绝大多数的blaGES基因,包括六个新的blaGES变种,频率较低的blaIMP基因是废水中唯一遇到的碳青霉烯酶基因;(ii)最主要的CPO物种是气单胞菌。,其中观察到新序列类型的显着多样性;(iii)从合并的下水道废水中检测到CPO,但不是来自单独的下水道废水,表明来自未识别的环境来源的CPO的负荷可能极大地有助于在进水废水中检测到它们。