Department of Environmental Health, National Institute of Public Health, Wako, Japan.
Department of Civil and Environmental Engineering, Tohoku University, Japan; Department of Urban Engineering, The University of Tokyo, Japan.
Water Res. 2024 Jun 15;257:121713. doi: 10.1016/j.watres.2024.121713. Epub 2024 May 10.
Pepper mild mottle virus (PMMoV) has been proposed as a potential indicator of human enteric viruses in environmental water and for viral removal during drinking water treatment. To investigate the occurrence and present forms of PMMoV and quantitative relations to norovirus GII and rotavirus A (RVA) in surface waters, 147 source water samples were collected from 21 drinking water treatment plants (DWTPs) in Japan between January 2018 and January 2021, and the concentrations of viruses in suspended and dissolved fractions were measured using real-time RT-PCR. PMMoV was detected in 81-100 % of samples in each sample month and observed concentrations ranged from 3.0 to 7.0 log copies/L. The concentrations of PMMoV were higher in dissolved fraction compared to suspended fractions, while different partitioning was observed for NoV GII depending on seasons. The concentrations of PMMoV were basically higher than those of norovirus GII (1.9-5.3 log copies/L) and RVA (1.9-6.6 log copies/L), while in 18 samples, RVA presented higher concentrations than PMMoV. Partial regions of VP7, VP4, and VP6 of the RVA in the 18 samples were amplified using nested PCR, and the genotypes were determined using an amplicon-based next-generation sequencing approach. We found that these source water samples included not only human RVA but also various animal RVA and high genetic diversity due to the existence of animal RVA was associated with a higher RVA concentration than PMMoV. Our findings suggest that PMMoV can be used as an indicator of norovirus GII and human RVA in drinking water sources and that the indicator performance should be evaluated by comparing to zoonotic viruses as well as human viruses.
胡椒轻斑驳病毒（PMMoV）已被提议作为环境水中人肠道病毒的潜在指示物，并可用于饮用水处理过程中去除病毒。为了调查地表水PMMoV 的发生和存在形式以及与诺如病毒 GII 和轮状病毒 A（RVA）的定量关系，本研究于 2018 年 1 月至 2021 年 1 月期间从日本 21 个饮用水处理厂（DWTP）采集了 147 个水源水样，并使用实时 RT-PCR 测量了悬浮和溶解部分的病毒浓度。在每个采样月份，PMMoV 均在 81-100%的样品中被检测到，观察到的浓度范围为 3.0 至 7.0 log 拷贝/L。与悬浮部分相比，PMMoV 在溶解部分的浓度更高，而 NoV GII 的分配则因季节而异。PMMoV 的浓度基本高于诺如病毒 GII（1.9-5.3 log 拷贝/L）和 RVA（1.9-6.6 log 拷贝/L），但在 18 个样品中，RVA 的浓度高于 PMMoV。使用巢式 PCR 扩增了这 18 个样品中 RVA 的 VP7、VP4 和 VP6 的部分区域，并使用基于扩增子的下一代测序方法确定了基因型。我们发现，这些水源样品不仅包括人类 RVA，还包括各种动物 RVA，由于动物 RVA 的存在，遗传多样性较高，与 PMMoV 相比，RVA 的浓度更高。我们的研究结果表明，PMMoV 可用作饮用水源中诺如病毒 GII 和人类 RVA 的指示物，并且应该通过与动物病毒以及人类病毒进行比较来评估指示物的性能。
