Bakhshi Bita, Afshari Nasim, Fallah Fatemeh
Tarbiat Modares University, Faculty of Medical Sciences, Department of Bacteriology, Tehran, Iran.
Islamic Azad University, Science & Research Branch, Faculty of Sciences, Saveh, Iran.
Braz J Microbiol. 2018 Jul-Sep;49(3):529-533. doi: 10.1016/j.bjm.2017.01.014. Epub 2018 Feb 8.
Shigellosis remains a serious public health problem and an important cause of morbidity and mortality worldwide. The aim of this study was to characterize fliC and the genetic relatedness of Shigella spp. isolated during a one-year period from children in a suspected outbreak in Tehran, Iran.
Fifty Shigella spp. were isolated from 3779 stool samples of children with diarrhea (prevalence rate: 1.32%). Among the isolates, 92% were characterized as Shigella sonnei, while 6% and 2% were identified as S. flexneri and S. boydii, respectively. S. dysenteriae was not recovered from the patients. All isolates were negative for fliC except for Shigella standard strains. The enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) profiles allowed differentiating the 50 isolates into 5 ERIC types, which were grouped into five clusters (ET1-ET5). Computer-assisted clustering of the strains showed a high degree of similarity among the isolates.
In conclusion, given the clonal correlation of the Shigella strains isolated in this study and the lack of fliC among them, we propose that probably a single or limited fliC-defected Shigella clone spread and caused the outbreak.
志贺氏菌病仍然是一个严重的公共卫生问题，也是全球发病和死亡的重要原因。本研究的目的是对从伊朗德黑兰疑似疫情中的儿童分离出的志贺氏菌属的fliC及其遗传相关性进行表征。
从3779份腹泻儿童粪便样本中分离出50株志贺氏菌属（患病率：1.32%）。在分离株中，92%被鉴定为宋内志贺氏菌，而6%和2%分别被鉴定为福氏志贺氏菌和鲍氏志贺氏菌。未从患者中分离出痢疾志贺氏菌。除志贺氏菌标准菌株外，所有分离株的fliC均为阴性。肠杆菌重复基因间共有序列聚合酶链反应（ERIC-PCR）图谱可将50株分离株分为5种ERIC类型，这些类型被分为五个簇（ET1-ET5）。菌株的计算机辅助聚类显示分离株之间具有高度相似性。
总之，鉴于本研究中分离出的志贺氏菌菌株的克隆相关性以及其中缺乏fliC，我们提出可能是单个或有限的fliC缺陷志贺氏菌克隆传播并导致了此次疫情爆发。
