Efficacy of parenteral vaccination against tuberculosis with heat-inactivated Mycobacterium bovis in experimentally challenged goats

Abstract

Tuberculosis (TB) in animals is a re-emerging disease with a wide range of hosts that causes large economic losses in livestock. Goats are particularly susceptible to TB and, in endemic areas, vaccination may be a valuable measure to control the disease. The main aim of this study was to evaluate the efficacy of parenteral vaccination of goats with a heat-inactivated Mycobacterium bovis (HIMB) vaccine, and compare it to M. bovis Bacille Calmette–Guérin (BCG) vaccine. Twenty-four goat kids were divided in 3 groups as following: HIMB vaccinated group (n = 8), BCG vaccinated group (n = 8) and unvaccinated group (n = 8). Afterwards, goats were experimentally challenged with Mycobacterium caprae by the endobronchial route. Antigen specific interferon-γ release assays and serology were performed after vaccination and challenge. Pathological and bacteriological parameters were evaluated after necropsy at 9 weeks post-challenge (p.c.). HIMB vaccine showed similar levels of protection to BCG in terms of volume reduction of thoracic TB lesions, presence of extra-pulmonary lesions, as well as a slight reduction of bacterial load in pulmonary lymph nodes. Moreover, HIMB vaccine did not induce interferences on the interferon-γ release assay based on reagents previously developed to differentiate infected from BCG vaccinated individuals. The results indicate that HIMB is a suitable vaccine candidate for further larger-scale trials under field conditions in goats.

Epidemiological characterization of Mycobacterium caprae strains isolated from wildlife in the Bieszczady Mountains, on the border of Southeast Poland

“…However, it is also the only area in Poland where TB cases have been reported in free-living animals: the disease has so far been diagnosed in European bison, boar, grey wolves, as well as one roe deer and one badger [1][2][3][4][5]8]. Given this situation, ongoing monitoring of the prevalence of animal tuberculosis should be conducted, and protective measures, such as the distribution of a TB vaccine, should be considered [46][47][48].…”

Animal Models of Tuberculosis Vaccine Research: An Important Component in the Fight against Tuberculosis

“…Interestingly, we found that the differences in BCG vaccination route might have an impact on the resulting immunoresponse characteristics. Accumulating data show that positivity to the single intradermal test and IGRA was observed in subcutaneously, intramuscularly [108,110], or intranasally [111] vaccinated kid goats, but not in orally vaccinated goats [112]. ese studies also indicated that the goat could be a more feasible model than cattle and NHPs because of its smaller size, lower cost, and caseous granulomatous and cavitary lesions that resemble those found in human TB patients [32,33].…”

Efficacy and Safety of BCG Vaccine for Control of Tuberculosis in Domestic Livestock and Wildlife

“…Vaccination with BCG appeared to prevent haematogenous dissemination of mycobacteria with extra-thoracic TB lesions only found in non-vaccinated goats ( 66 ). A comparison of parenterally administered BCG and heat-inactivated M. bovis vaccines showed that both vaccines provided similar levels of protection against a M. caprae experimental challenge, with a reduction in the volume of thoracic TB lesions and extra-pulmonary lesions compared to non-vaccinates ( 67 ). Use of mycobacterial DIVA reagents, ESAT-6 and CFP10, in the IFN-γ test was able to differentiate TB-infected from BCG-vaccinated goats.…”