The United States of America as represented by the Secretary of Agriculture;Icahn School of Medicine at Mount Sinai;St. Jude Children's Research Hospital
The present invention relates, in general, to attenuated swine influenza viruses having an impaired ability to antagonize the cellular interferon (IFN) response, and the use of such attenuated viruses in vaccine and pharmaceutical formulations. In particular, the invention relates to attenuated swine influenza viruses having modifications to a swine NS1 gene that diminish or eliminate the ability of the NS 1 gene product to antagonize the cellular IFN response. These viruses replicate in vivo, but demonstrate decreased replication, virulence and increased attenuation, and therefore are well suited for use in live virus vaccines, and pharmaceutical formulations.