Trichomonas vaginalis is a protozoan pathogen of the human urogenital tract. The World Health Organization (WHO) estimates that trichomoniasis accounts for more than half of all curable sexually transmitted infections

Trichomonas vaginalis is a protozoan pathogen of the human urogenital tract. The World Health Organization (WHO) estimates that trichomoniasis accounts for more than half of all curable sexually transmitted infections (STIs) worldwide.1 Although accurate surveillance data are lacking, there were an estimated five million new cases of trichomoniasis each year in the US during the late 1990s, exceeding similar figures for gonorrhea and chlamydial infections combined.2 The prevalence of T. vaginalis has been reported to be as high as 26% among female STD clinic patients and 22% among HIV-positive women.3 Recurrent infections are common in women, predominantly due to untreated sexual partners.4 Transmitted primarily by sexual intercourse, T. vaginalis causes vaginitis in women and urethritis in men. While trichomoniasis is well recognised as an aetiological cause of vaginitis, the proportion of non-gonococcal urethritis in men due to T. vaginalis has been estimated to be between 11 and 18%.5 A substantial proportion of infections are asymptomatic, necessitating reliable testing methods. Trichomoniasis is also implicated in various other genito-urinary syndromes, including cervicitis, epididymitis and prostatitis.5 Associations between maternal trichomoniasis and premature rupture of the membranes and pre-term delivery have been reported,6–8 and there is mounting evidence of an association with cervical cancer.9–14