what causes protozoan parasite called Trichomonas vaginalis
Trichomoniasis (or âtrichâ) is a very common sexually transmitted disease (STD) that is caused by infection with a protozoan parasite called Trichomonas vaginalis.Although symptoms of the disease vary, most women and men who have the parasite cannot tell they are infected.richomoniasis (or âtrichâ) is a very common sexually transmitted disease (STD) that is caused by infection with a protozoan parasite called Trichomonas vaginalis.