Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Arcadia, Private Bag X323, Pretoria, 0007, South Africa.
Food Environ Virol. 2018 Mar;10(1):16-28. doi: 10.1007/s12560-017-9316-2. Epub 2017 Aug 4.
Norovirus (NoV) GII.4 is the predominant genotype associated with gastroenteritis pandemics and new strains emerge every 2-3 years. Between 2008 and 2011, environmental studies in South Africa (SA) reported NoVs in 63% of the sewage-polluted river water samples. The aim of this study was to assess whether wastewater samples could be used for routine surveillance of NoVs, including GII.4 variants. From April 2015 to March 2016, raw sewage and effluent water samples were collected monthly from five wastewater treatment plants in SA. A total of 108 samples were screened for NoV GI and GII using real-time RT-qPCR. Overall 72.2% (78/108) of samples tested positive for NoVs with 4.6% (5/108) GI, 31.5% (34/108) GII and 36.1% (39/108) GI + GII strains being detected. Norovirus concentrations ranged from 1.02 × 10 to 3.41 × 10 genome copies/litre for GI and 5.00 × 10 to 1.31 × 10 genome copies/litre for GII. Sixteen NoV genotypes (GI.2, GI.3, GI.4, GI.5, GI.6, GII.2, GII.3, GII.4, GII.7, GII.9, GII.10, GII.14, GII.16, GII.17, GII.20, and GII.21) were identified. Norovirus GII.2 and GII.17 co-dominated and the majority of GII.17 strains clustered with the novel Kawasaki 2014 variant. Sewage surveillance facilitated detection of Kawasaki 2014 in SA, which to date has not been detected with surveillance in children with gastroenteritis <5 years of age. Combined surveillance in the clinical setting and environment appears to be a valuable strategy to monitor emergence of NoV strains in countries that lack NoV outbreak surveillance.
诺如病毒（NoV）GII.4 是与肠胃炎大流行相关的主要基因型，每隔 2-3 年就会出现新的菌株。2008 年至 2011 年，南非（SA）的环境研究报告称，受污染河水样本中有 63%存在诺如病毒。本研究旨在评估废水样本是否可用于常规监测诺如病毒，包括 GII.4 变体。2015 年 4 月至 2016 年 3 月，从南非五个污水处理厂每月采集一次原生污水和出水水样。使用实时 RT-qPCR 对 108 个水样进行了 GI 和 GII 型诺如病毒的筛查。总共 72.2%（78/108）的样本诺如病毒检测呈阳性，其中 4.6%（5/108）为 GI 型，31.5%（34/108）为 GII 型，36.1%（39/108）为 GI+GII 型。诺如病毒浓度范围为 GI 型 1.02×10 至 3.41×10 基因组拷贝/升，GII 型 5.00×10 至 1.31×10 基因组拷贝/升。鉴定出 16 种诺如病毒基因型（GI.2、GI.3、GI.4、GI.5、GI.6、GII.2、GII.3、GII.4、GII.7、GII.9、GII.10、GII.14、GII.16、GII.17、GII.20 和 GII.21）。诺如病毒 GII.2 和 GII.17 共同占主导地位，大多数 GII.17 株与新型川崎 2014 变异株聚集在一起。污水监测有助于在南非发现川崎 2014，迄今为止，在年龄小于 5 岁的肠胃炎儿童监测中尚未发现该病毒。在缺乏诺如病毒暴发监测的国家，在临床和环境中联合监测似乎是监测诺如病毒株出现的有效策略。
