Yi Guan 及同事研究了最近在中國人群中出現(xiàn)的H7N9流感病毒的演化史,。通過在流感爆發(fā)后不久所進行的實地監(jiān)測,，作者提供了若干新禽流感病毒的基因組：34個H7N7基因組、3個H7N9基因組和19個H9N2基因組,、以及從在2000年和2013年間在中國南方收集到的存檔分離菌種得到的197個序列,。他們發(fā)現(xiàn),，H7病毒至少在兩個獨立場合可能是從鴨傳給雞的,，與H9N2病毒的再分類產(chǎn)生了H7N9這個爆發(fā)類別以及另一個以前沒有被識別出的H7N7類別。這些H7N7病毒在實驗中能感染雪貂,，而且雖然還沒有什么證據(jù)證明這些病毒已適應(yīng)了哺乳動物,，但作者提出，目前的疫情威脅可能會超越H7N9病毒,。(生物谷Bioon.com)
生物谷推薦的英文摘要
Nature doi:10.1038/nature12515
The genesis and source of the H7N9 influenza viruses causing human infections in China
Tommy Tsan-Yuk Lam, JiaWang, Yongyi Shen, Boping Zhou, Lian Duan, Chung-Lam Cheung, Chi Ma,Samantha J. Lycett, Connie Yin-Hung Leung, Xinchun Chen, Lifeng Li, Wenshan Hong, Yujuan Chai, Linlin Zhou,Huyi Liang, Zhihua Ou, Yongmei Liu, Amber Farooqui, David J. Kelvin, Leo L. M. Poon, David K. Smith1,Oliver G. Pybus7,8, Gabriel M. Leung1,3, Yuelong Shu9, Robert G. Webster10, Richard J. Webby10, Joseph S. M. Peiris,Andrew Rambaut, Huachen Zhu & Yi Guan
A novel H7N9 influenza A virus first detected in March 2013 has since caused more than 130 human infections in China, resulting in 40 deaths. Preliminary analyses suggest that the virus is a reassortant of H7, N9 and H9N2 avian influenza viruses, and carries some amino acids associated with mammalian receptor binding, raising concerns of a new pandemic. However, neither the source populations of the H7N9 outbreak lineage nor the conditions for its genesis are fully known. Using a combination of active surveillance, screening of virus archives, and evolutionary analyses, here we show that H7 viruses probably transferred from domestic duck to chicken populations in China on at least two independent occasions. We show that the H7 viruses subsequently reassorted with enzootic H9N2 viruses to generate the H7N9 outbreak lineage, and a related previously unrecognized H7N7 lineage. The H7N9 outbreak lineage has spread over a large geographic region and is prevalent in chickens at live poultry markets, which are thought to be the immediate source of human infections. Whether the H7N9 outbreak lineage has, or will, become enzootic in China and neighbouring regions requires further investigation. The discovery here of a related H7N7 influenza virus in chickens that has the ability to infect mammals experimentally, suggests that H7 viruses may pose threats beyond the current outbreak. The continuing prevalence of H7 viruses in poultry could lead to the generation of highly pathogenic variants and further sporadic human infections, with a continued risk of the virus acquiring human-to-human transmissibility.
