Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Environ Sci Technol. 2010 Sep 15;44(18):7116-22. doi: 10.1021/es100346a.
We investigated the prevalence, seasonal dependence, and genetic diversity of noroviruses (NoVs) in the Tamagawa River, which runs through a densely populated region in Tokyo, Japan, from April 2003 to March 2004. A total of 60 water samples were collected from five sites from upstream to downstream along the river, and 500 mL of which was concentrated using the "cation-coated filter method". Of the 60 samples tested, genogroup I (GI) and GII NoVs were detected from 28 (47%) and 18 (30%) samples, respectively. GIV NoV was successfully detected from 2 (3%) samples with a newly developed seminested RT-PCR assay specific for GIV. The occurrence of NoVs in the river was significantly higher in winter/spring than in summer/autumn and also in mid- to downstream rather than upstream. A total of 176 different NoV strains were identified from river water samples based on the phylogenetic analysis of partial capsid gene sequences. GI, GII, and GIV strains were clustered into 7 (GI/1, 2, 4, 5, 8, 9, and 11), 8 (GII/2, 3, 4, 5, 6, 11, 12, and 16), and 1 (GIV/1) genotypes, respectively. The results suggest that genetically diverse NoV strains are circulating between human populations and aquatic environments.
我们调查了流经日本东京人口稠密地区的玉川河诺如病毒（NoV）的流行情况、季节性依赖关系和遗传多样性。2003 年 4 月至 2004 年 3 月，我们从该河的五个地点从上游到下游共采集了 60 个水样，并使用“阳离子涂层滤器法”对其中的 500 毫升进行浓缩。在测试的 60 个样本中，GI 和 GII 诺如病毒分别从 28 个（47%）和 18 个（30%）样本中检测到。通过新开发的针对 GIV 的半巢式 RT-PCR 检测法，成功从 2 个（3%）样本中检测到 GIV NoV。河水中 NoV 的发生在冬春季节明显高于夏秋季节，并且在中下游地区高于上游地区。根据部分衣壳基因序列的系统发育分析，从河水样本中鉴定出了 176 种不同的 NoV 株。GI、GII 和 GIV 株分别聚类为 7 种（GI/1、2、4、5、8、9 和 11）、8 种（GII/2、3、4、5、6、11、12 和 16）和 1 种（GIV/1）基因型。结果表明，遗传多样的 NoV 株在人群和水生环境之间传播。
