This invention relates to vaccines and in particular to the combination of non-integrating, replication-incompetent retroviral vectors (NIV) with virus-like particle (VLP) vaccines to induce an immune response in an animal host following administration to the host. This combination results in a novel vaccine strategy for delivering priming and boost doses, wherein an effective amount of an NIV is administered to the host, followed by an effective amount of a VLP. The concept can be broadly applied to infectious disease vaccines and also to cancer vaccines.
