Recombinant poxviruses, such as vaccinia, are provided that comprises
a segment comprised of (A) a first DNA sequence encoding a polypeptide that is
foreign to poxvirus and (B) a poxvirus transcriptional regulatory sequence, wherein
(i) said transcriptional regulatory sequence is adjacent to and exerts transcriptional
control over said first DNA sequence and (ii) said segment is positioned within
a nonessential genomic region of said recombinant poxvirus. Vaccines, carriers,
cells, and media comprising recombinant poxviruses, and methods of immunization
with recombinant poxviruses, also are provided.