Also called Sleeping Sickness. Protozoan disease caused by Trypanosoma Brucei.Encyclopedia Entry for African Trypanosomiasis :African Trypanosomiasis (sleeping sickness): African trypanosomiasis is spread by the tsetse fly, which is common to many African countries. The World Health Organization (WHO) estimates that nearly 450,000 cases occur each year. Symptoms of the disease include fever, headaches, joint pains, and itching in the early stage, and confusion, sensory disturbances, poor coordination, and disrupted sleep cycles in the second stage. If the disease goes untreated in its first stage, it causes irreparable neurological damage; if it goes untreated in its second stage, it is fatal.