Emergence, spread, and impact of high-pathogenicity avian influenza H5 . . . The currently circulating high-pathogenicity avian influenza (HPAI) virus of the subtype H5 causes variable illness and death in wild and domestic birds and mammals, as well as in humans This virus evolved from the Goose Guangdong lineage of the HPAI H5 virus, which emerged in commercial poultry in China in 1996, spilled over into wild birds, and spread through Asia, Europe, Africa, and North