Highly pathogenic avian influenza virus (HPAIV) A H5, particularly clade 2.3.4.4, has caused worldwide outbreaks since 2014. Wild bird migration is a key factor in HPAIV H5 global dispersal. This study uses phylogenetic analyses of bird movement tracking and virus genome sequences to demonstrate that seasonal bird migration explains the global dispersal of clade 2.3.4.4, synchronizing with virus lineage movements. The study reveals differing exposed bird orders at geographical origins and destinations of HPAIV H5 lineage movements, including some under-discussed orders. The findings highlight the importance of integrating bird behavior and life history in avian influenza studies.

Qiqi Yang, Ben Wang, Phillipe Lemey, Lu Dong, Tong Mu, R. Alex Wiebe, Fengyi Guo, Nidia Sequeira Trovão, Sang Moo Park, Nicola Lewis, Joseph L.-H. Tsui, Sumali Bajaj, Yachang Cheng, Luojun Yang, Yuki Haba, Bingying Li, Guogang Zhang, Oliver G. Pybus, Huaiyu Tian, Bryan Grenfell