Mycobacterium bovis bacille Calmette-Guérin (BCG) results in positive tuberculin skin test results in a dose-dependent fashion in white-tailed deer (Odocoileus virginianus)

Authors: Palmer, Mitchell; Waters, Wade; Thacker, Tyler

Submitted to: Research in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/10/2020
Publication Date: 2/1/2020
Citation: Palmer, M.V., Waters, W.R., Thacker, T.C. 2020. Vaccination of white-tailed deer (Odocoileus virginianus) with Mycobacterium bovis bacille Calmette-Guérin (BCG) results in positive tuberculin skin test results in a dose-dependent fashion. Research in Veterinary Science. 129:70-73. https://doi.org/10.1016/j.rvsc.2020.01.010.
DOI: https://doi.org/10.1016/j.rvsc.2020.01.010

Interpretive Summary: Mycobacterium bovis is the cause of tuberculosis in most mammalian species, most notably cattle; however, many species of deer are also susceptible. In North America, tuberculosis has been identified in both captive and free-ranging deer. Captive deer are tested for tuberculosis following many of the same guidelines applied to cattle, including tuberculin skin testing. Both captive and free-ranging deer and elk have been implicated as the source of infection for many cattle herds. Vaccination with the human tuberculosis vaccine M. bovis BCG has been considered as one possible tool to aid in eradication of tuberculosis from cattle and deer. Studies in cattle have demonstrated that BCG vaccination can induce false positive tuberculin skin test reactions in some cattle. We orally vaccinated white-tailed deer with BCG and showed that vaccination can induce false positive skin test reactions in some deer and that the rate of false positive reactions increases with increasing vaccine dose.

Technical Abstract: Mycobacterium bovis is the cause of tuberculosis in most mammalian species, most notably cattle and other members of the family Bovidae; however, many species of the family Cervidae are also susceptible. In North America, tuberculosis has been identified in both captive and free-ranging cervids. Captive cervids are tested for tuberculosis following many of the same guidelines applied to cattle, including intradermal tuberculin testing using M. bovis purified protein derivative (PPD). Both captive and free-ranging deer and elk have been implicated as the source of infection for many cattle herds. Vaccination with the human vaccine M. bovis BCG has been considered as one possible tool to aid in eradication of tuberculosis from cattle and both captive and free-ranging cervids. Studies in cattle have demonstrated that BCG vaccination can induce false positive intradermal tuberculin test reactions in some cattle. Similar findings have been reported for red deer. We orally vaccinated white-tailed deer with BCG and showed that vaccination can induce false positive skin test reactions in some deer and that the rate of false positive reactions increases with increasing vaccine dose.