Abstract: The present invention relates to compositions and methods for inducing an immune response against influenza virus in a subject. In some embodiments, the present invention provides a composition comprising a nucleoside-modified nucleic acid molecule encoding at least one influenza virus antigen, such as a hemagglutinin antigen or a fragment thereof, neuraminidase antigen or a fragment thereof, nucleoprotein antigen or a fragment thereof, matrix protein 1 antigen or a fragment thereof, or matrix-2 ion channel antigen or a fragment thereof.

Abstract: The disclosure provides RNA vaccines for seasonal influenza virus as well as methods of using the vaccines.

Abstract: Provided herein are immunization regimens for inducing an immune response (e.g., and antibody response) against influenza virus. In specific aspects, the immunization regimens involve the administration of a chimeric hemagglutinin (HA), a headless HA or another influenza virus stem domain based construct (e.g., the HA stem domain or a fragment thereof) to a subject. In certain aspects, the immunization regimens also involve the administration of an influenza virus neuraminidase immunogen. Also provided herein are immunogenic/vaccine compositions for use in methods of immunizing or immunization regimens for human subjects against influenza virus.