Abstract: A canine influenza recombinant virus includes HA and NA genes of ZJCIV canine influenza virus as well as six internal genes PA, PB1, PB2, M, NP and NS of a PR8 virus. The nucleotide sequence of the HA gene is selected from the group consisting of: (1) a nucleotide sequence encoding an amino acid sequence of SEQ ID NO.1; (2) a nucleotide sequence encoding an amino acid sequence which has at least 98% sequence identity to the amino acid sequence of SEQ ID NO.1. The nucleotide sequence of the NA gene is selected from the group consisting of: (1) a nucleotide sequence encoding an amino acid sequence of SEQ ID NO.2; (2) a nucleotide sequence encoding an amino acid sequence which has at least 98% sequence identity to the amino acid sequence of SEQ ID NO.2.

Abstract: A PR8 recombinant influenza virus contains an HA and/or NA gene of H1, H3, H4, H5, H6, H7, H9 or H10 subtype influenza virus, and 6 internal genes (PB1, PB2, PA, NP, M and NS genes) of PR8 virus, in which the NS and/or NP gene have the following mutation sites: the NS2 protein encoded by the NS gene has an E67S point mutation, E74S point mutation, or E67S/E74S point mutation, and the NP protein encoded by the NP gene has a G132A point mutation.