Ecological Drivers and Evolutionary Dynamics of Trypanosoma brucei rhodesiense in Nigeria: Implications for Sleeping Sickness Epidemiology and Control

This dissertation characterises the ecological drivers and evolutionary dynamics of Trypanosoma brucei rhodesiense, the causative agent of acute human African trypanosomiasis (sleeping sickness), in Nigeria, addressing the gap in understanding whether this human-pathogenic trypanosome is currently active or present in Nigerian wildlife and livestock reservoirs, and its implications for public health. Although T. b. rhodesiense is documented from East and Central Africa, its presence in Nigerian wildlife reservoirs has never been systematically screened despite the presence of suitable Glossina vectors, creating a public health surveillance blind spot. The dissertation employs a cross-species, multi-zone ecological and molecular epidemiology design, collecting blood samples from wildlife (using dart gun and cage trapping), cattle, and human contacts in tsetse-endemic areas of the North East, North Central, and South South geopolitical zones. T. brucei subsp. identification is achieved by the SRA gene PCR, and population genetics analysis using microsatellite markers characterises genetic structure. Tsetse apparent density and infection rates are measured by biconical trapping at 40 sites. Ecological niche modelling using MaxEnt identifies suitable T. b. rhodesiense habitat across Nigeria. The dissertation proposes the Nigerian Sleeping Sickness Ecological Risk Framework (NSSERF) as an original theoretical and applied contribution. Preliminary findings identify T. brucei genetic material in Kob and buffalo from Taraba State, warranting further investigation. Keywords: Trypanosoma brucei rhodesiense, sleeping sickness, ecological drivers, evolutionary dynamics, Nigeria.