Trypanosoma species

Microbiology

Flagellated vector-borne protozoan parasite of mammals in the genus Trypanosoma
Generally have three morphological states: epimastigote, amastigote, and trypomastigote
- T. cruzi has an intracellular amastigote while T. brucei do not, but rather multiply as trypomastigotes in the bloodstream
- Amastigotes are commonly intracellular, and are small with a very short flagellum
- Epimastigotes have a flagellum that runs along and connects as an undulating membrane, with the kinetoplast anterior to the nucleus
- Trypomastigotes have a similar flagellum as epimastigotes, but with the kinetoplast posterior to the nucleus

Two major groups
- Stercoraria, which multiply discontinuously in the mammal as amastigotes, and develop in the vector in the hindgut
  - Transferred via contaminated feces
  - e.g. T. cruzi
- Salivaria, which multiply continuously in the mammal as trypomastigotes, and develop in the vector in the salivary glands
  - Transferred via saliva
  - e.g. T. brucei
Three species infect humans
- T. cruzi, which causes Chagas disease
- T. brucei gambiense and T. brucei rhodesiense, which cause African sleeping sickness