Oral vaccination of white-tailed deer using a recombinant Bacillus Calmette-Guérin vaccine expressing the Borrelia burgdorferi outer surface protein A: prospects for immunocontraception.

PROBLEM: Reduction of excess numbers of white-tailed deer (Odocoileus virginianus) is a prime example of a potential use for immunocontraception as a means of wildlife population management. Oral vaccination appears to be the most pragmatic way to deliver immunocontraceptive vaccines to free-roaming populations of deer, but there was little, if any, prior evidence that oral vaccination is a viable concept in deer.

METHOD OF STUDY: We used live Bacillus Calmette-Guérin (BCG) in a recombinant form (rBCG), which expressed Borrelia burgdorferi outer surface protein A, to test whether deer vaccinated orally with a specific antigen expressed in a live vector produce detectable antibody titers.

RESULTS: The data indicate that oral vaccination of deer with an expressed antigen is feasible, as demonstrated by peak antibody titers to the expressed antigen. Also, peak titers measured by enzyme-linked immunosorbent assay were highest in orally vaccinated deer: 1600 in deer vaccinated by injection and 6400 in those vaccinated orally.

CONCLUSIONS: The results of this study demonstrate that it is feasible to vaccinate deer orally with a live vector.