avian influenza virus subtype h9n2 outbreaks in chickens

presentation design avian influenza virus subtype h9n2 outbreaks poultry chcikens chickens outbreak genetic characterization biological antigenic evolution subtype poultry chicken broiler layer viruses low pathogenic h5n1 h5n8 h7n9 h7 h5 ha 3d report outbreak disease mortality dead sick genes rna