Emily Tangie - IUIS Beijing ICI 2019 Presentation
Emily Tangie - The Effect of Malaria on the Efficacy of BCG vaccine against Mycobacterium tuberculosis in mice
Bacillus Calmette Guerin (BCG) remains the only licensed vaccine against tuberculosis. It is known to protect against severe disseminated forms of tuberculosis (TB) in infants but show poor efficacy against pulmonary TB in adults. Coinfections have been reported as one of the factors implicated in inefficacy. BCG coverage coincides with some regions where TB and malaria overlap. Thus, malaria could alter the ability of BCG to protect against TB. We compared virulent Plasmodium berghei and less virulent Plasmodium chabaudi; their effects on the B cells, effector and memory T cells following BCG vaccination and the outcome on the efficacy of BCG after MtbH37Rv aerosol challenge in wild type C57Bl/6 mice. P. berghei induced a significant loss of the central memory T cells and follicular B cells. Both species caused significant depletion of the marginal zone B cells but induced a strong effector T cell response enhanced by BCG vaccination. However, there was no loss of protection against Mycobacterium tuberculosis following aerosol challenge. Therefore, a post malaria exposure does not alter the efficacy of BCG vaccine against Mycobacterium tuberculosis irrespective of the virulence.