Human African Trypanosomiasis (HAT)

About Human African Trypanosomiasis (HAT):

• It is also known as sleeping sickness.
• It is caused by protozoan parasites transmitted by infected tsetse flies and endemic in sub-Saharan Africa.
• It takes 2 forms, depending on the subspecies of the infecting parasite:
  • Trypanosoma brucei gambiense: It is found in 24 countries of west and central Africa, currently accounts for 92% of reported cases and causes a chronic illness.
  • A person can be infected for months or even years without major signs or symptoms. When evident symptoms emerge, often the disease is advanced with the central nervous system already affected.
  • Trypanosoma brucei rhodesiense: It is found in 13 countries of eastern and southern Africa, accounts for 8% of reported cases and causes an acute disease.
  • First signs and symptoms emerge a few weeks or months after infection. The disease develops rapidly with multi-organ invasion, including the brain.
• Tsetse flies inhabit sub-Saharan Africa and only certain species transmit the disease. Rural populations which depend on agriculture, fishing, animal husbandry or hunting are the most exposed. 
• To date, WHO has validated the elimination of the gambiense form of HAT in seven countries: Togo (2020), Benin (2021), Ivory Coast (2021), Uganda (2022), Equatorial Guinea (2022), Ghana (2023) and Chad (2024).