Final answer:
Trypanosoma gambiense causes West African trypanosomiasis, while Trypanosoma cruzi causes American trypanosomiasis. Both diseases are spread by insect bites and can be fatal if left untreated.
Step-by-step explanation:
Trypanosoma gambiense and Trypanosoma cruzi are species of flagellate protozoa within the genus Trypanosoma. Trypanosoma gambiense is the causative agent of West African trypanosomiasis, commonly known as African sleeping sickness. This disease is spread by the tsetse fly (Glossina spp.) and can be fatal if untreated. Trypanosoma cruzi, on the other hand, causes American trypanosomiasis, also known as Chagas disease. Chagas disease is spread by the triatomine bug, often called the kissing bug. Both diseases involve the protozoa entering the bloodstream and potentially causing severe health issues.
For East African trypanosomiasis, the correct causative agent is Trypanosoma brucei gambiense. These parasites can attack red blood cells and invade the central nervous system, leading to symptoms such as confusion, difficulty sleeping, and lack of coordination. Without treatment, the infection can result in a coma and eventually death. Effective control measures and greater surveillance have led to a reduction in reported cases, particularly for African sleeping sickness.