Department of Water Protection Engineering and Environmental Microbiology, The faculty of Geoengineering University of Warmia and Mazury in Olsztyn, Prawocheńskiego 1, 10-719 Olsztyn, Poland.
Int J Environ Res Public Health. 2021 Jan 11;18(2):563. doi: 10.3390/ijerph18020563.
The aim of this study is to describe the drug resistance and virulence of enterococci in river water sampled downstream (DRW) and upstream (URW) from the wastewater discharge point, to determine the pool of virulent and drug-resistant enterococci in untreated wastewater (UWW) and the extent to which these bacteria are eliminated from hospital wastewater (HWW) and municipal wastewater treated (TWW) by biological and mechanical methods in a wastewater treatment plant (WWTP). A total of 283 strains were identified with the use of culture-dependent methods and PCR, including seven different species including and which were predominant in all analyzed samples. Majority of the strains were classified as multidrug resistant (MDR), mostly on streptomycin and trimethoprim. Strains isolated from wastewater and DRW harbored genes conditioning phenotypic resistance to vancomycin, the highest percentage of vancomycin-resistant strains (57.0%), mostly strains harboring C1 genes (27.6%), was noted in TWW. More than 65.0% of the isolated strains had different virulence genes, the highest number of isolates were positive for cell wall adhesin A and sex pheromones , and which participate in the induction of virulence. Many of the strains isolated from TWW were resistant to a higher number of drugs and were more virulent than those isolated from UWW and HWW. The enterococci isolated from DRW and wastewater were characterized by similar multidrug resistance and virulence profiles, and significant correlations were observed between these groups of isolates. These findings suggest that pathogenic enterococci are released with TWW and can spread in the river, pose a serious epidemiological threat and a risk to public health.
本研究的目的是描述取自污水处理排放点下游（DRW）和上游（URW）河水的肠球菌的耐药性和毒力，确定未经处理废水（UWW）中有毒和耐药肠球菌的菌群，以及这些细菌在污水处理厂（WWTP）中通过生物和机械方法从医院废水（HWW）和市政废水处理（TWW）中被消除的程度。使用依赖于培养的方法和 PCR 共鉴定了 283 株，包括七种不同的物种，其中 和 是所有分析样本中的主要优势菌。大多数菌株被归类为多药耐药（MDR），主要对链霉素和甲氧苄啶耐药。从废水和 DRW 中分离的菌株携带基因，赋予对万古霉素的表型耐药性，在 TWW 中检测到最高百分比的万古霉素耐药菌株（57.0%），主要是携带 C1 基因的菌株（27.6%）。超过 65.0%的分离菌株具有不同的毒力基因，分离株中阳性率最高的是细胞壁黏附素 A 和性信息素 、 和 ，它们参与了毒力的诱导。许多从 TWW 中分离的菌株对更多种类的药物具有耐药性，并且比从 UWW 和 HWW 中分离的菌株更具毒力。从 DRW 和废水分离的肠球菌具有相似的多药耐药和毒力谱特征，并且观察到这些分离株组之间存在显著相关性。这些发现表明，致病肠球菌随着 TWW 被释放出来，并可能在河流中传播，对公共卫生构成严重的流行病学威胁和风险。
