Abstract:
Mycobacterium africanum (M. africanum) comprises two phylogenetic lineages within the Mycobacterium tuberculosis complex (MTBC). M. africanum was first described and isolated in 1968 from sputum of a Senegalese patient with pulmonary tuberculosis (TB) and it has been increasingly identified as an important cause of human TB, particularly prevalent in West Africa. The restricted geographical distribution of M. africanum, in contrast to widespread global distribution of other species of MTBC requires explanation. Available data indicate that M. africanum may also have important differences in transmission, pathogenesis and host-pathogen interactions which could affect the evaluation of new TB intervention tools (diagnostics and vaccines)- those currently in use and those under development. The unequal geographical distribution and spread of MTBC species means that individual research findings from one country or region cannot be generalized across the continent. Thus, generalisability of data from previous and ongoing research studies on MTBC may be inaccurate and inappropriate. Thus, a major re-think is required for the design and structures of future clinical trials of new interventions. The West, Central, East and Southern African EDCTP Networks of Excellence across provide opportunities to take forward these pan- Africa studies. More investments into molecular, epidemiological, clinical, diagnostic, and immunological studies across the African continent are required to enable further understanding host-M.africanum interactions, leading to development of more specific diagnostics, biomarkers, host-directed therapies and vaccines for TB.
