Oral vaccination of white-tailed deer (Odocoileus virginianus) with Mycobacterium bovis Bacillus Calmette-Guerin (BCG)

Authors: Palmer, Mitchell; Thacker, Tyler; Waters, Wade; ROBBE-AUSTERMAN, SUELEE - Animal And Plant Health Inspection Service (APHIS)

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2014
Publication Date: 5/7/2014
Publication URL: http://handle.nal.usda.gov/10113/58892
Citation: Palmer, M.V., Thacker, T.C., Waters, W.R., Robbe-Austerman, S. 2014. Oral vaccination of white-tailed deer (Odocoileus virginianus) with Mycobacterium bovis Bacillus Calmette-Guerin (BCG). PLoS One. 9(5):e97031.

Interpretive Summary: The bacterium Mycobacterium bovis causes tuberculosis in many animal species including cattle, deer and humans. Due to public health concerns over transmission of tuberculosis from cattle to humans, a USDA program to eliminate tuberculosis from cattle (bovine tuberculosis) has been in place since 1917. Complete elimination of bovine tuberculosis has been difficult, in part due to infected wildlife (primarily white-tailed deer) transmitting tuberculosis to cattle. One approach to dealing with this wildlife reservoir of tuberculosis is to vaccinate wildlife. We demonstrate that oral vaccination with a human tuberculosis vaccine (BCG) decreases disease severity in white-tailed deer. Deer with milder disease are less likely to transmit tuberculosis to cattle. This is the first step in developing oral baits that could be used to vaccinate white-tailed deer.

Technical Abstract: Wildlife reservoirs of Mycobacterium bovis represent serious obstacles to the eradication of tuberculosis from livestock, particularly cattle. In Michigan, USA tuberculous white-tailed deer transmit M. bovis to other deer and cattle. One approach in dealing with this wildlife reservoir is to vaccinate deer, thus interfering with the intraspecies and interspecies transmission cycles. Thirty-three white-tailed deer were assigned to one of two groups; oral vaccination with 1 X 10**8 colony-forming units of M. bovis BCG Danish (n=17); and non-vaccinated (n=16). One hundred eleven days after vaccination deer were infected intratonsilarly with 300 colony-forming units of virulent M. bovis. At examination, 150 days after vaccination, BCG vaccinated deer had fewer gross and microscopic lesions, fewer tissues from which M. bovis could be isolated, and fewer late stage granulomas with extensive liquefactive necrosis. Fewer lesions, especially those of a highly necrotic nature should decrease the potential for dissemination of M. bovis within the host and transmission to other susceptible hosts.