ntroduction
Mycobacterium tuberculosis, a facultative intracellular microbe belonging to the M. tuberculosis complex, is the most important cause of tuberculosis (TB) in humans. In addition to M. tuberculosis, other members of the M. tuberculosis complex that are able to cause tuberculosis in humans include Mycobacterium bovis, Mycobacterium africanum, Mycobacterium microti and Mycobacterium canetti (Aro et al., 2015). Tuberculosis, an old yet emerging in- fectious disease, is one of the leading causes of human morbidity and mortality (Nguta et al., 2015b). In the year 2013, the World