Key Laboratory of Protein and Peptide Pharmaceutical, National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
Cell Host Microbe. 2013 Oct 16;14(4):446-52. doi: 10.1016/j.chom.2013.09.001. Epub 2013 Sep 19.
Initial genetic characterizations have suggested that the influenza A (H7N9) viruses responsible for the current outbreak in China are novel reassortants. However, little is known about the pathways of their evolution and, in particular, the generation of diverse viral genotypes. Here we report an in-depth evolutionary analysis of whole-genome sequence data of 45 H7N9 and 42 H9N2 viruses isolated from humans, poultry, and wild birds during recent influenza surveillance efforts in China. Our analysis shows that the H7N9 viruses were generated by at least two steps of sequential reassortments involving distinct H9N2 donor viruses in different hosts. The first reassortment likely occurred in wild birds and the second in domestic birds in east China in early 2012. Our study identifies the pathways for the generation of diverse H7N9 genotypes in China and highlights the importance of monitoring multiple sources for effective surveillance of potential influenza outbreaks.
初步的遗传特征分析表明，导致当前中国流感疫情的甲型 H7N9 病毒是新型重组病毒。然而，人们对其进化途径知之甚少，特别是不同病毒基因型的产生。在这里，我们报告了对近期在中国流感监测工作中从人类、家禽和野生鸟类中分离出的 45 株 H7N9 和 42 株 H9N2 病毒的全基因组序列数据进行的深入进化分析。我们的分析表明，H7N9 病毒是由至少两个连续的重配步骤产生的，涉及不同宿主中的不同 H9N2 供体病毒。第一次重配可能发生在野鸟中，第二次发生在中国东部的家禽中，时间在 2012 年初。我们的研究确定了中国产生多样化 H7N9 基因型的途径，并强调了监测多种来源对于有效监测潜在流感爆发的重要性。
