"Influenza Type A Viruses and Subtypes" "Influenza Type A Viruses and Subtypes" US Centers for Disease Control and Prevention influenza A (H1N1) a new potentially lethal strain H3N2 subtype of the influenza A virus influenza A virus Center for Disease Control and Prevention nine known subtypes influenza type A influenza A (H1N1) www.cdc.gov/flu/avianflu/influenza-a-virus-subtypes.htm H7N3 H3N2 subtype of the influenza A virus influenza A (H1N1) H3N2 subtype of the influenza A virus H3N2 subtype of the influenza A virus Avian Influenza Type A Center for Disease Control and Prevention US Centers for Disease Control and Prevention two types of bird flu Centers for Disease Control Avian Influenza Type A a new potentially lethal strain influenza A (H1N1) CDC H3N2 subtype of the influenza A virus influenza A influenza A (H1N1) nine known subtypes wild birds influenza A other avian influenza H7 viruses have infected people There are many different strains of avian flu: US Centers for Disease Control and Prevention type A influenza virus influenza A virus influenza A influenza A (H1N1) says three main subtypes avian influenza viruses 18 different versions eleven versions of this protein influenza virus subtype H3N2 subtype of the influenza A virus influenza A virus other avian influenza H7 viruses have infected people Influenza Type A Viruses and Subtypes CDC Avian Influenza Type A CDC US Centers for Disease Control and Prevention Center for Disease Control and Prevention US Centers for Disease Control and Prevention