Location: Infectious Bacterial Diseases Research
Project Number: 5030-32000-222-007-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 1, 2020
End Date: Sep 30, 2024
Evaluate bovine tuberculosis vaccine baits in white-tailed deer, which can be used to decrease/eliminate deer-to-deer and deer-to-cattle transmission of Mycobacterium bovis. Additionally, ARS will work with Cooperator to develop improved diagnostic tests for bovine tuberculosis.
Two significant obstacles to eradication include the spillover of Mycobacterium bovis from infected wild white-tailed deer to cattle and performance deficiencies in existing diagnostic tests for cattle. Through field research, USDA, APHIS, Wildlife Services has determined the appropriate bait material for use in oral vaccination of free- ranging white-tailed deer. ARS will evaluate the feasibility of incorporating the human tuberculosis vaccine, Mycobacterium bovis strain BCG into the baits and the degree to which deer consuming BCG baits develop immune responses consistent with successful vaccination. This work will occur in Ames, Iowa using animals from the ARS white-tailed breeding herd. Available diagnostic tests for cattle are not accurate enough to remove from a herd all infected cattle with confidence that no infected animals remain (false negatives). Likewise, available tests may identify non-infected animals as infected (false positives) resulting in the euthanasia of healthy animals ARS will work with Cooperator to evaluate and validate modifications to existing tests as well as develop novel tests for bovine tuberculosis. Evaluation and validation will use experimentally infected animals in ARS BSL3 large animal containment facilities and established models of experimental infection of cattle with Mycobacterium bovis. Samples from naturally infected animals will also be used for evaluation/validation. These will be obtained through cooperation with APHIS VS staff when M. bovis-infected herds are identified.