Figure 2.

Salivarian trypanosomes have a vast near-worldwide distribution. Tsetse-transmitted T. brucei parasites occur only in sub-Saharan Africa, with the human-infective T. b. gambiense being present in West and Central Africa, while T. b. rhodesiense is restricted to East Africa. T. congolense has a similar sub-Saharan Africa distribution. Due to the possibility of mechanical transmission, T. vivax has a wider distribution and occurs in sub-Saharan Africa as well as South America. T. evansi has an even wider geographic distribution, including locations on four different continents. T. equiperdum has a rather unique distribution pattern as it does not use insect vector transmission as a means of propagation.