Immunogenic compositions and methods for vaccinating humans and animals against enveloped viruses, and more particularly against influenza viruses. Immunogenic compositions are composed of internal moieties of an enveloped virus. Such internal moieties are more highly conserved between different viral strains than are their external moiety counterparts. Consequently, these immunogenic compositions have an increased likelihood of generating immuno-protective responses in humans and animals against enveloped viruses that are strain independent. Methods are also disclosed that increase the ability of the immunogenic compositions to generate immuno-protective responses against their target viruses.
