Fig. 2.

Phylogenetic analysis of the surface genes of H9N2 avian influenza viruses collected from live poultry markets in Hubei Province between 2013 to 2017. A HA gene. B NA gene. Solid triangles indicate strains isolated in this study. Solid circles indicate H9N2 strains that caused human infection. Solid squares indicate genotype 57 strains. For each node, bootstrap values ≥ 70% are shown. The tree was created using the neighbor-joining method and bootstrapped with 1000 replicates using MEGA6.0.