African trypanosomiasis

Definition

A vector-borne parasitic disease of humans and mammals caused by subspecies of Trypanosoma brucei and transmitted exclusively by tsetse flies (genus Glossina). The chronic form (T. b. gambiense, West and Central Africa) spreads mainly human-to-human, while the acute form (T. b. rhodesiense, East and Southern Africa) is zoonotic with wild and domestic animal reservoirs. Also called sleeping sickness due to neurological progression.

Etymology

New Latin Trypanosoma (trypanosome genus, from Greek trypanon 'borer' + sōma 'body') + -iasis 'disease condition'; African from geographic distribution.

Example

Glossina palpalis, a riverine tsetse species, is the principal vector of T. b. gambiense in West African foci, with transmission intensity linked to human-fly contact near water sources.

Synonyms

• African sleeping sickness
• sleeping sickness
• human African trypanosomiasis

Related Terms

• tsetse fly
• Glossina
• trypanosome
• vector competence
• Zoonosis
• gambiense
• rhodesiense
• parasite reservoir
• medical entomology

Usage Notes

Distinguish from American trypanosomiasis (Chagas disease), transmitted by triatomine bugs. Specialists reserve 'sleeping sickness' for the human disease; animal trypanosomiasis caused by T. congolense or T. vivax is termed nagana. The gambiense/rhodesiense distinction is epidemiologically critical: rhodesiense infections progress rapidly (weeks to months) and require urgent treatment, while gambiense infections may remain asymptomatic for years.