Fig. 3From: Diversity and distribution of type A influenza viruses: an updated panorama analysis based on protein sequencesPhylogenetic diversity and distribution of H3 subtypes of IAVs based on HA sequences. H3 subtype IAVs were classified into three primary lineages, H3.1, H3.2 and H3.3. H3.1 corresponded to H3 subtype AIVs, and several secondary lineages within H3.1, H3.1a-H3.1c, were designated. H3.2 corresponded to many HuIVs and SIVs circulating worldwide. H3.3 corresponded to the EIVs circulating from 1963 to nowadaysBack to article page