Antigenic and Molecular Characterization of Avian Influenza A(H9N2) Viruses, Bangladesh
Figure 4. . Host range and pathogenicity determinants in avian influenza (H9N2) viruses isolated from different poultry species in Bangladesh during 2008–2011. Numbers in parentheses indicate number of viruses containing specific amino acid residues of the 44 virus isolates analyzed. Blue indicates the 11 genes that were assessed; red indicates the residues that are critical for influenza pathogenesis, enhanced replication in mammalian hosts, or those that are identical to residues present in human influenza viruses; green indicates unique substitutions in the viruses. HA, hemagglutinin; NA, neuraminidase; M, matrix; NS, nonstructural; NP, nucleoprotein; PA and PB, polymerase genes.