Wellcome Trust [107769/Z/10/Z]; UK Medical Research Council (MRC) Newton Fund collaborative award [200344/Z/15/Z]; Wellcome Trust strategic award [096527]; UK Economic and Social Research Council; MRC; Wellcome Trust core award [092654]; Wellcome Trust through a senior Fellowship in Clinical Science [206316/Z/17/Z]; DELTAS Africa Initiative [DEL-15-003]; African Academy of Sciences's Alliance for Accelerating Excellence in Science in Africa; New Partnership for Africa's Development Planning and Coordinating Agency; UK government; MRC [MC_PC_16025] Funding Source: UKRI