The present invention relates to an immunogenic fusion protein which comprises at least, on the C-terminal side, a first peptide composed of the S protein deleted of the transmembrane domain thereof located at the N-terminal end thereof, of a hepatitis B virus (HBV) isolate, and on the N-terminal side, a second peptide composed of the transmembrane domain and of the ectodomain of at least one envelope protein of a hepatitis C virus (HCV) isolate. The subject matter of the invention is also a hybrid nucleic acid molecule encoding said fusion protein, and also a vector comprising said hybrid nucleic acid molecule, a subviral particle comprising said fusion protein, an immunogenic composition comprising at least said fusion protein, or at least said hybrid nucleic acid molecule, or at least said subviral particle, and a cell line for the production of said fusion protein, or of said hybrid nucleic acid molecule, or of said subviral particle.
