FIG 2.

Avian influenza viruses used and evolutionary relationships of H5 and H7 subtype avian influenza viruses. A phylogenetic tree for amino acid sequences of the H5 and H7 HA1 protein was generated by the minimum-evolution method using MEGA software, version 5.2. The scale bar represents 0.01 or 0.005 units of amino acid per site for H5 or H7, respectively; black circles indicate LPAIVs. The tree is based on HA sequences presented in this study GenBank accession numbers are given (ns, not sequenced).