Trypanosoma brucei rhodesiense is a parasitic protozoan responsible for one form of sleeping sickness, known as African trypanosomiasis. It is transmitted to humans through the bite of infected tsetse flies, primarily found in eastern and southern Africa. This parasite infects the bloodstream and can lead to severe neurological symptoms if left untreated. The disease caused by T. b. rhodesiense progresses rapidly, often resulting in death within months. Symptoms include fever, headaches, joint pain, and changes in behavior. Early diagnosis and treatment are crucial, typically involving medications such as pentamidine or suramin to combat the infection effectively.