African trypanosomiasis

World Health Organization: staging criteria[32]World Health Organization. Guidelines for the treatment of human African trypanosomiasis. Jun 2024 [internet publication]. https://www.who.int/publications/i/item/9789240096035 ​​

Cases of gambiense human African trypanosomiasis (HAT) and rhodesiense HAT are classified in two stages, according to invasion of the central nervous system.

• First-stage disease (also called early stage or haemolymphatic stage):

  • ≤5 white blood cells (WBC)/microlitre AND no trypanosomes in the cerebrospinal fluid (CSF)

• Second-stage disease (also called late stage or meningoencephalitic stage):

  • >5 WBC/microlitre OR trypanosomes in the CSF

The second stage of gambiense HAT can be further classified as severe.

• Severe second-stage disease (also called severe meningoencephalitic stage): ≥100 WBC/microlitre in the CSF with or without trypanosomes.