THIS INVENTION RELATES TO A RECOMBINANT MONONEGAVIRALES VIRUS VECTOR HARBORING AN ADDITIONAL TRANSCRIPTION UNIT COMPRISING A FOREIGN GENE, WHICH IS OPERATIVELY LINKED WITH AN UPSTREAM MONONEGAVIRALES VIRUS GENE START (GS) SEQUENCE AND A DOWNSTREAM MONONEGAVIRALES VIRUS GENE END (GE) SEQUENCE. IN ADDITION THE INVENTION RELATES TO A VACCINE AGAINST A MICROBIAL PATHOGEN COMPRISING SUCH A RECOMBINANT MONONEGAVIRALES VIRUS VECTOR.