Trypanosomiasis

Definition

Any disease caused by parasitic kinetoplastid protozoans of the genus Trypanosoma, transmitted to vertebrate hosts through the bite of infected arthropod vectors. The two principal human forms are African trypanosomiasis (sleeping sickness), spread by tsetse flies (Glossina spp.), and American trypanosomiasis (Chagas disease), spread by triatomine bugs (subfamily Triatominae). The parasite undergoes complex development within the vector, involving transformation between procyclic and metacyclic trypomastigote stages before becoming infective to mammals. Trypanosomiasis also causes severe veterinary disease in livestock (nagana, surra, dourine), creating major economic and conservation impacts in sub-Saharan Africa and tropical regions worldwide.

Etymology

New Latin, from Trypanosoma (genus name, from Greek trypanon "borer, auger" + sōma "body") + -iasis "diseased condition"

Example

Control of African trypanosomiasis in cattle herds often targets the tsetse vector through insecticide-impregnated targets or sterile insect technique, rather than treating infected animals directly, because drug-resistant trypanosome strains are increasingly common.

Synonyms

• trypanosomosis

Related Terms

• vector-borne disease
• tsetse fly
• kissing bug
• Chagas disease
• sleeping sickness
• kinetoplastida
• metacyclogenesis
• Zoonosis

Usage Notes

Specialists distinguish between the two human forms by geographic epithet (African vs. American) or eponym (Chagas disease); "trypanosomiasis" alone usually requires context to specify which form or host group is meant. The term encompasses veterinary as well as human disease, and usage in livestock contexts often employs regional names (nagana, surra) rather than the umbrella term. Contrast with leishmaniasis, caused by related kinetoplastids but transmitted by phlebotomine sand flies with different clinical manifestations.