Blood smear of African trypanosomiasis

The two Trypanosoma brucei subspecies that cause African trypanosomiasis, T. b. gambiense and T. b. rhodesiense, are indistinguishable morphologically. A typical trypomastigote has a small kinetoplast located at the posterior end, a centrally located nucleus, an undulating membrane, and a flagellum running along the undulating membrane, leaving the body at the anterior end. Trypomastigotes are the only stage found in patients. Trypanosomes range in length from 14 to 33 micrometers.
(A) T. brucei ssp in thick blood smears stained with Giemsa.
(B) Trypomastigotes of T. brucei ssp in a blood smear stained with Giemsa.
(C) T. brucei ssp in a thin blood smear stained with Giemsa. The trypomastigote is beginning to divide; dividing forms are seen in African trypanosomes but not in American trypanosomes.