2013年2月起，我国长三角地区爆发了新型H7N9禽流感疫情。新型H7N9病毒起源于早先存在的H7N3，H7N9和H9N2病毒之间的基因组重排。我们在前期研究中根据时空动力学分析结果，提出新型H7N9病毒起源的进化模型，并在湖州的禽类样品中检测到H7N9和H9N2的共流行、新重排病毒H9N9（即H7N9起源的进化中间体），以及与H7N9最相关的H9N2毒株，建议湖州至少是新型H7N9病毒的起源地之一。然而，H9N9存在的确凿证据还不够充分，H7N9是否存在多地起源也不清楚。本项目围绕这两个核心科学问题，以湖州地区家禽和野鸟为对象，借助454高通量测序技术，深入调查新型H7N9病毒相关禽流感病毒的流行情况，寻找H9N9存在的进一步证据，并采用时空动力学分析方法研究湖州与其他地区禽流感病毒的进化关系，阐述新型H7N9病毒的起源机制和过程，为预警未来可能发生的新型流感病毒重排提供科学依据。

Since February, 2013, a novel H7N9 avian influenza virus (AIV) has led to an outbreak of human infection in Yangtze River Delta Region of China. The H7N9 virus was demonstrated to originate via genomic reassortment events between three earlier AIVs, H7N3, H7N9 and H9N2. In our previous study, we proposed an evolutionary model of the H7N9 formation based on temporal dynamic analysis, and detected co-circulation of H7N9 and H9N2, H7N9-related reassortant intermediates H9N9 viruses, as well as a closest genetically related H9N2 virus to the H7N9 among poultry in Huzhou, China, during April 2013, suggesting that Huzhou is, at least, one of the geographic origins of the novel H7N9 virus. However, the evidence for the existence of H9N9 virus in Huzhou is still inadequate, and whether the H7N9 has various geographic origins also remains unclear. To address these questions, in this study, we will apply high-throughput sequencing to investigate the molecular epidemiology of H7N9 and its-related AIVs among poultry and wild birds in Huzhou, and to search for further evidence of existence of H9N9 virus. In addition, we will investigate the genetically relationship of H7N9 and its-related AIVs between Huzhou and other regions of China by phylogenetic analyses and spatio-temporal dynamic analyses. The results obtained from this project will not only enhance the understanding of the origin mechanism and process of the H7N9 virus, but also provide valuable information for predicting potential outbreak of new influenza reassortants in the future.

2013年2月起，我国长三角地区爆发了新型H7N9禽流感疫情。新型H7N9病毒起源于早先存在的H7N3，H7N9和H9N2病毒之间的基因组重排。我们在前期研究中根据时空动力学分析结果，提出新型H7N9病毒起源的进化模型，并在湖州的禽类样品中检测到H7N9和H9N2的共流行、新重排病毒H9N9（即H7N9起源的进化中间体），以及与H7N9最相关的H9N2毒株，建议湖州至少是新型H7N9病毒的起源地之一。然而，H9N9存在的确凿证据还不够充分，H7N9是否存在多地起源也不清楚。本项目围绕这两个核心科学问题，以湖州地区家禽和野鸟为对象，借助Illumina HiSeq高通量测序技术平台，深入调查新型H7N9病毒相关禽流感病毒的流行情况，结果显示荧光定量PCR检测H7/N9阳性的样本在全基因组测序分析结果中并未找寻到H7/N9序列信息，流感相关病毒只发现了H1N1序列信息。也许测序样本的基数影响了最终结果信息，但是二代测序的手段必将使得生物学研究新领域不断被挖掘探索。对活禽中的禽流感H7N9监测需进一步加强，建议在疫情发生前采取主动的活禽市场关闭措施，以尽量减少人感染H7N9病毒的风险。