Medical School, Anhui University of Science and Technology, Huainan, 232001, Anhui, People's Republic of China.
NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China.
Arch Virol. 2021 May;166(5):1305-1312. doi: 10.1007/s00705-020-04934-7. Epub 2021 Feb 26.
Echovirus 6 (E6) is associated with various clinical diseases and is frequently detected in environmental sewage. Despite its high prevalence in humans and the environment, little is known about its molecular phylogeography in mainland China. In this study, 114 of 21,539 (0.53%) clinical specimens from hand, foot, and mouth disease (HFMD) cases collected between 2007 and 2018 were positive for E6. The complete VP1 sequences of 87 representative E6 strains, including 24 strains from this study, were used to investigate the evolutionary genetic characteristics and geographical spread of E6 strains. Phylogenetic analysis based on VP1 nucleotide sequence divergence showed that, globally, E6 strains can be grouped into six genotypes, designated A to F. Chinese E6 strains collected between 1988 and 2018 were found to belong to genotypes C, E, and F, with genotype F being predominant from 2007 to 2018. There was no significant difference in the geographical distribution of each genotype. The evolutionary rate of E6 was estimated to be 3.631 × 10 substitutions site year (95% highest posterior density [HPD]: 3.2406 × 10-4.031 × 10 substitutions site year) by Bayesian MCMC analysis. The most recent common ancestor of the E6 genotypes was traced back to 1863, whereas their common ancestor in China was traced back to around 1962. A small genetic shift was detected in the Chinese E6 population size in 2009 according to Bayesian skyline analysis, which indicated that there might have been an epidemic around that year.
肠道病毒 6 型（E6）与多种临床疾病相关，并且经常在环境污水中被检测到。尽管其在人类和环境中普遍存在，但对其在中国大陆的分子系统地理学知之甚少。在这项研究中，从 2007 年至 2018 年间收集的 21539 例手足口病（HFMD）临床标本中，有 114 份（0.53%）为 E6 阳性。使用 87 株具有代表性的 E6 分离株的完整 VP1 序列（包括本研究中的 24 株）来研究 E6 分离株的进化遗传特征和地理分布。基于 VP1 核苷酸序列差异的系统进化分析表明，在全球范围内，E6 分离株可分为 6 种基因型，命名为 A 至 F。1988 年至 2018 年间收集的中国 E6 分离株属于基因型 C、E 和 F，2007 年至 2018 年间以基因型 F 为主。每个基因型的地理分布没有显著差异。贝叶斯 MCMC 分析估计 E6 的进化率为 3.631×10-4 个替换/位点/年（95%最高后验密度[HPD]：3.2406×10-4～4.031×10-4 个替换/位点/年）。E6 基因型的最近共同祖先可追溯到 1863 年，而中国的共同祖先可追溯到 1962 年左右。贝叶斯天空线分析显示，2009 年中国 E6 种群规模发生了微小的遗传变化，这表明当年可能发生了一次流行。
