Sleeping sickness: perspectives in African trypanosomiasis

African trypanosomiasis has recently been relegated in the league table of the major infectious diseases. However, in the light of the serious instability of most countries on the African continent, due to civil unrest, political turmoil and unabated fratricidal wars, mass movements of refugees across national borders, to and from sleeping sickness foci, the resurgence and spread of this disease is on the increase. These movements of people en masse are analogous to those which, at the turn of the century led to outbreaks of sleeping sickness killing thousands of people in areas which had previously not experienced this disease. The present situation is compounded by severe budgetary constraints and lack of human resources, making it virtually impossible to undertake surveillance programmes and to deliver health services to already destabilished populations. Current molecular and biochemical studies on the African trypanosome suggest a need for reappraisal of strategies for the diagnosis and treatment of both the chronic and acute forms of sleeping sickness. These studies have also highlighted the complexity of animal trypanosomiasis (nagana). There is an urgent need to understand first, fundamental elements of protection by the immune system, especially in the light of recent findings on the interaction(s), at the outset, between T-cell subsets, B cells, cytokines and parasites and/or parasite derived components (trypanokines), and second, the mechanisms of action of the drugs currently used.