Trichomonadida is an order of anaerobic protists, included with the parabasalids. Members of this order are referred to as trichomonads.
Some organisms in this order include:
Species in this order typically have four to six flagella at the cell's apical pole, one of which is recurrent - that is, it runs along a surface wave, giving the aspect of an undulating membrane. Like other parabasalids, they typically have an axostyle, a pelta, a costa, and parabasal bodies. In Histomonas only one flagellum and a reduced axostyle are found, and in Dientamoeba, both are absent.
Most species are either parasites or other endosymbionts of animals.
Trichomonads reproduce by a special form of longitudinal fission, leading to large numbers of trophozoites in a relatively short time. Cysts never form, so transmission from one host to another is always based on direct contact between the sites they occupy.[1]
The preferred treatment for trichomonad infection is Metronidazole.[2]