Immune responses and protective efficacy of a recombinant swinepox virus expressing HA1 against swine H1N1 influenza virus in mice and pigs

► This is the first construction of recombinant SPV expressing HA1 of H1N1 SIV. ► The recombinant rSPV-HA1 can express HA1 of H1N1 SIV in vitro. ► rSPV-HA1 can induce specific humoral and cell-mediated immune responses in animals. ► Administration of rSPV-HA1 provides a complete protection against H1N1 SIV in pigs.