TY - JOUR AU - Neumann, Gabriele AU - Kawaoka, Yoshihiro T1 - Host Range Restriction and Pathogenicity in the Context of Influenza Pandemic T2 - Emerging Infectious Disease journal PY - 2006 VL - 12 IS - 6 SP - 881 SN - 1080-6059 AB - Influenza A viruses cause pandemics at random intervals. Pandemics are caused by viruses that contain a hemagglutinin (HA) surface glycoprotein to which human populations are immunologically naive. Such an HA can be introduced into the human population through reassortment between human and avian virus strains or through the direct transfer of an avian influenza virus to humans. The factors that determine the interspecies transmission and pathogenicity of influenza viruses are still poorly understood; however, the HA protein plays an important role in overcoming the interspecies barrier and in virulence in avian influenza viruses. Recently, the RNA polymerase (PB2) protein has also been recognized as a critical factor in host range restriction, while the nonstructural (NS1) protein affects the initial host immune responses. We summarize current knowledge of viral factors that determine host range restriction and pathogenicity of influenza A viruses. KW - Influenza A virus KW - pathogenesis KW - host range KW - HA KW - NA KW - PB2 KW - perspective DO - 10.3201/eid1206.051336 UR - https://wwwnc.cdc.gov/eid/article/12/6/05-1336_article ER - End of Reference