东亚地区大天鹅迁徙在H5N2禽流感病毒重组和传播中的潜在作用  

Potential Role of Whooper Swans(Cygnus cygnus)Migration in Reassortment and Dissemination of Avian Influenza A(H5N2)in Eastern Asia

作　　者：贾茹 高如意 茹文东 孔德生 张国钢[1] JIA Ru;GAO Ruyi;RU Wendong;KONG Desheng;ZHANG Guogang(Key Laboratory of Forest Protection of National Forestry and Grassland Administration,Ecology and Nature Conservation Insti-tute,Chinese Academy of Forestry,National Bird Banding Center,Beijing 100091,China;Sanmenxia Swan Lake National Urb-an Wetland Park Management Bureau of Henan,Sanmenxia 472000,China)

机构地区：[1]中国林业科学研究院森林生态环境与自然保护研究所,全国鸟类环志中心,国家林业和草原局森林保护学重点实验室,北京100091 [2]河南省三门峡市天鹅湖国家城市湿地公园管理处,三门峡472000

出　　处：《陆地生态系统与保护学报》2022年第1期43-49,I0002-I0005,共11页Terrestrial Ecosystem and Conservation

基　　金：国家林业和草原局项目(213023721203);国家自然科学基金(32070530)。

摘　　要：【目的】大天鹅(Cygnus cygnus)广泛分布于东亚地区,被认为是H5亚型禽流感病毒的易感鸟类。揭示大天鹅迁徙对H5N2病毒在东亚传播中所起的潜在作用,为研究H5N2病毒的重组和传播提供科学依据。【方法】2018年12月和2019年1月,在三门峡库区采集越冬大天鹅新鲜粪便共1866份;2018和2019年春季和秋季,沿着大天鹅的迁徙路线采集其它野生水鸟新鲜粪便样品共6351份并进行了检测。【结果】分离出14株H5N2亚型禽流感病毒,其中H5蛋白裂解位点处的序列均为PQRETR↓GLF,属于低致病性禽流感病毒。14株病毒8个基因片段的同源性均≥99.8%,这表明分离到的14株病毒基本一致。系统发育分析结果表明,14株分离株均属于欧亚谱系,在地理位置上均呈现出以亚洲为主的特点,涉及到的主要国家包括蒙古国、韩国、孟加拉国以及中国南部地区,与大天鹅等雁鸭类迁徙路线相吻合。【结论】H5N2分离株可能是由不同地点不同亚型的低致病性禽流感病毒重组而来,这些地点包括大天鹅越冬地、停歇地和繁殖地等。该病毒随着大天鹅的长距离迁徙进行传播,并且存在着传播至中国西部进行重组与进化成高致病性禽流感病毒的潜在风险。【Objective】Whooper swans,widely distributed throughout eastern Asia,are highly susceptible to H5 AIVs.Combining the migration routes of whooper swans,we explored the potential role of whooper swans in reassortment and transmission of H5N2 virus in eastern Asia.【Method】1866 fresh faeces from wintering whooper swans in the Sanmenxia Reservoir Area,China,in December 2018 and January 2019,and 6351 faeces from multiple wild waterfowl species along the migration route of whooper swans in spring and autumn of 2018 and 2019 were collected and tested.【Result】14 H5N2 AIVs were isolated.Analyses of the H5 gene reveal the cleavage site in all 14 viruses to be PQRETR↓GLF,corresponding to a low-pathogenic pathotype.The homology of the 14 H5N2 AIVs eight genes exceeds 99.8%,indicating that the 14 isolated viruses were almost identical.These 14 H5N2 AIVs all belong to a Eurasian lineage,characterised by Asia in geographical position,mainly including Mongolia,South Korea,Bangladesh and southern China,where were located on the migration routes of whooper swans and other wild ducks in eastern Asia.【Conclusion】H5N2 isolates with small sequence divergence from whooper swans in Sanmenxia Reservoir Area were likely generated by reassortment of low pathogenic AIVs isolated from a diverse set of wild waterfowl at multiple distant locations,including the wintering,stopover and breeding sites of whooper swans who carried the viruses over long distances during their migration.We believed that virus had the potential risk of spreading to the west of China for reassortment and evolution into a highly pathogenic avian influenza virus.

关 键 词：东亚 H5N2 迁徙路线 重组 大天鹅 

分 类 号：Q958.1[生物学—动物学]