The present invention relates to the discovery of a high titer hybrid-virus vector that gives rise to high titer virus like vesicles (VLVs) that can be used as a vaccine. The invention includes compositions and methods of generating an evolved hybrid-virus vector vaccine and selecting high titer VLVs, methods of treating and/or preventing or immunizing against, a specific disease or disorder, and methods of inducing a memory T cell and B cell immune response in a subject administered the VLV composition produced thereby. Furthermore, the invention encompasses a pharmaceutical composition for vaccinating a subject as well as a high titer protein expression system.
