The present disclosure provides nucleic acids comprising nucleotide sequences encoding hepatitis C virus (HCV) E1 and/or E2 polypeptides and/or one or more T-cell epitope polypeptides. The nucleic acids can comprise one or more modifications. The nucleic acids can be self-amplifying. The present disclosure provides compositions comprising the nucleic acids. The present disclosure provides methods of inducing an immune response to HCV in an individual, comprising administering to the individual a composition of the present disclosure.