title: Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus.
abstract: The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.
authors: Ministry of Education Key Laboratory for Earth System Modeling, and Center for Earth System Science, Tsinghua University, Beijing, China.
authors: Yanjie
authors: Y
authors: Xu
authors: Ministry of Education Key Laboratory for Earth System Modeling, and Center for Earth System Science, Tsinghua University, Beijing, China.|Joint Center for Global Change Studies, Beijing 100875, China.
authors: Peng
authors: P
authors: Gong
authors: Department of Animal and Plant Sciences, University of Sheffield, S10 2TN Sheffield, UK.|Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, The Netherlands.
authors: Ben
authors: B
authors: Wielstra
authors: Ministry of Education Key Laboratory for Earth System Modeling, and Center for Earth System Science, Tsinghua University, Beijing, China.|Resource Ecology Group, Wageningen University, Droevendaalsesteeg 3a, 6708 PB Wageningen, The Netherlands.
authors: Yali
authors: Y
authors: Si
mesh_terms: D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D046090:Anseriformes / Q000821:virology; D004196:Disease Outbreaks; D005060:Europe / Q000453:epidemiology; D005202:Asia, Eastern / Q000453:epidemiology; D005426:Flight, Animal / Q000502:physiology; D053124:Influenza A Virus, H5N1 Subtype / Q000502:physiology*; D005585:Influenza in Birds / Q000453:epidemiology* / Q000635:transmission / Q000821:virology; D012621:Seasons; D015047:Zoonoses / Q000453:epidemiology* / Q000635:transmission / Q000821:virology