Discussion
Trypanosoma suis Ochmann 1902 is a tsetse-transmitted pathogen of pigs in sub-Saharan Africa. The importance of
T. suis as the missing link between
T. brucei and
T. congolense was recognised in the 1950s, but this obscure parasite of pigs remained undetected for nearly 60 years, until 2015 when a
T. brucei-like trypanosome found in tsetse midguts collected from Tanzania matched
T. suis on archival Giemsa-stained slides from the 1950s using two independent species-specific PCR tests1.
T. suis has an ITS-1 region similar in length to
T. simiae, which may explain why
T. suis has escaped detection in the past. We have optimised culture conditions for
T. suis and are developing a molecular toolbox for this organism, adapting resources available for other trypanosome species. Transfection with a fluorescent protein gene will allow us to detect the trypanosome by fluorescence microscopy inside the tsetse fly vector and follow its developmental cycle. Historical observations indicate that
T. suis colonises the salivary glands and the proboscis of the tsetse fly, an intriguing amalgamation of the strategies employed by its closest relatives,
T. brucei and
T. congolense.
1. Hutchinson & Gibson Infect Genet Evol.2015, 36, 381-388.
2. Peel & Chardome Ann Soc Belg Med Trop 1954, 34, 277-296