Global epidemiology of Trichomonas vaginalis.

Despite having the highest prevalence of any sexually transmitted infection (STI) globally, there is a dearth of data describing Trichomonas vaginalis (TV) incidence and prevalence in the general population. The lack of basic epidemiological data is an obstacle to addressing the epidemic. Once considered a nuisance infection, the morbidities associated with TV have been increasingly recognised over the past decade, highlighting the importance of this pathogen as a public health problem. Recent developments in TV diagnostics and molecular biology have improved our understanding of TV epidemiology. Improved characterisation of the natural history of TV infection has allowed us to hypothesise possible explanations for observed variations in TV prevalence with age. Direct and indirect hormonal effects on the female genital tract provide a likely explanation for the greater burden of persistent TV infection among women compared with men. Further characterisation of the global epidemiology of TV could enhance our ability to respond to the TV epidemic.