African Sleeping Sickness: From Basic Biology to Future Directions

African Sleeping Sickness is a Neglected Tropical Disease (NTD) which poses a significant health risk to impoverished populations in 36 Sub-Saharan African countries. It is a devastating disease caused by the protozoan parasite Trypanosoma brucei, which is transmitted to mammals via the bite of infected tsetse flies. The disease manifests in two stages: the hemolymphatic stage and the meningoencephalitic stage. In the latter stage, it invades the Central Nervous System (CNS) and can be fatal if left untreated. It is caused by morphologically indistinguishable species of Trypanosoma brucei in both humans and animals, where in humans it is known as Human African Trypanosomiasis (HAT) and in animals as nagana. Despite ongoing control efforts, there is no vaccine, and the current treatments are toxic, expensive, and difficult to administer. Vaccine development is continually hindered due to the parasite’s ability to rapidly change its Variant Glycoprotein Surface (VSG) coat, which helps it evade the host’s immune responses. However, with the introduction of new drugs like fexinidazole and acoziborole, treatment is becoming more accessible. Understanding the genetics of the disease can be substantial in the identification of host and parasite genes, as well as parasite-derived molecules that influence disease pathogenesis. These factors can then be targeted for therapeutic intervention. Further research is essential to develop effective long-term solutions. Genetic studies offer valuable insights into host-parasite interactions and may help identify new targets for therapy. Molecules such as TbKHC1 (Kinesin Heavy Chain 1) and TbAdc (Adenylate Cyclase) from the parasite, along with host immune factors like TNFɑ, HLA-G, and Daxx, play important roles in disease progression and immune response modulation. Investigating these genetic and molecular factors could aid in overcoming vaccine challenges and reducing the socioeconomic burden of the disease. Improving diagnosis, treatment, and surveillance while ensuring proper distribution of funds for research is necessary to achieve the 2030 elimination goal set by the WHO. While it is possible to eliminate it, consistent efforts are the only way to achieve it, as the disease has the tendency to reemerge.