Protection Against Influenza A(H5N1) by Primary Infection with Influenza A(H3N2) and MVA-based Vaccination

Influenza A viruses belong to the family of the orthomyxoviridae that consists of five genera: Thogoto virus, Isavirus and Influenza virus A, B and C. The generae of influenza viruses are distinguished based on their membrane channel protein, genome size and surface glycoprotein(s).[1] Influenza A viruses are classified based on their surface glycoproteins: hemagglutinin (HA) and neuraminidase (NA). So far 16 HA subtypes and 9 NA subtypes have been identified based on genetic and antigenic analysis.[2] The nomenclature of influenza viruses is based on: subtype, host of origin (except humans), isolation site (geographical), strain number, year of isolation and followed by the description of the antigenic subtype, e.g. A/Chicken/ Netherlands/1/03 (H7N7).