Sleeping Sickness Trypanosomiasis

Human African trypanosomiasis, commonly known as sleeping sickness, is a parasitic disease caused by infection with Trypanosoma protozoa transmitted through tsetse fly bites. The disease manifests in two forms corresponding to distinct parasite subspecies: West African sleeping sickness (caused by Trypanosoma brucei gambiense) and East African sleeping sickness (caused by Trypanosoma brucei rhodesiense). East African sleeping sickness, transmitted by tsetse flies in specific focal areas including western Kenya, presents with rapid clinical progression and more severe symptoms. The disease follows a two-stage progression beginning with hemolymphatic disease (fever, headache, joint pain) followed by meningoencephalitic disease with sleep disturbances, confusion, and eventual coma if untreated.

Historically, sleeping sickness was endemic in focal areas of western Kenya, particularly in the Lake Victoria region where tsetse flies are present. The disease affected pastoral and agricultural communities in these areas, causing mortality and disability among people and livestock. Knowledge of the disease led to some communities avoiding affected areas, disrupting traditional pastoralist migration and land use patterns. The disease was incorporated into colonial medical concerns and later became a priority for post-independence health authorities. Early interventions emphasized tsetse fly control through habitat management and pesticide application, reducing vector populations in affected areas.

Kenya's sleeping sickness elimination efforts extended over decades, combining vector control, active case-finding, and treatment of identified cases. The government worked with WHO and international partners to conduct surveillance for human cases and establish treatment protocols. Pentamidine was used for early-stage disease treatment, while arsenicals were used for late-stage meningoencephalitic disease despite toxicity concerns. Community health worker involvement in surveillance enabled identification of suspected cases for confirmation and treatment. Tsetse fly control programs, including sterile insect technique in some areas, aimed to eliminate the vector completely from affected regions.

In 2025, the World Health Organization validated Kenya as having eliminated human African trypanosomiasis as a public health problem, making Kenya the tenth country to achieve this milestone globally. This validation recognized the sustained efforts over many years to reduce disease transmission and eliminate foci where the disease persisted. The milestone reflects successful combination of vector control, active surveillance, and treatment, eliminating the disease's transmission potential. No new human cases had been documented for extended periods before validation, confirming absence of active transmission.

Kenya's achievement of sleeping sickness elimination demonstrates successful long-term disease control through sustained public health effort and international partnership. The elimination of focal diseases requires persistence over decades and commitment to surveillance preventing re-emergence from external sources. Kenya's success with sleeping sickness provides a model for controlling other vector-borne diseases endemic in limited geographic areas. Continued surveillance and preparedness for potential re-introduction from neighboring countries remain necessary to maintain elimination status. The achievement represents significant public health progress in reducing burden of neglected tropical diseases affecting rural populations.

Our Kenya

Explorer

Sleeping Sickness Trypanosomiasis

See Also

Sources

Table of Contents