Trichomonas vaginalis (TV) is the most prevalent curable sexually transmitted infection (STI) globally. Yet at least 80% of TV infections are asymptomatic, though even asymptomatic infections are a public health concern.
In addition to the risk of transmission to sex partners, TV infection has been associated with as much as a 2.7-fold increase in the risk of HIV acquisition, a 1.3-fold increase in the risk of preterm labour, and a 4.7-fold increase in the risk of pelvic inflammatory disease.
A recent review in the journal Sexually Transmitted Infections (STI) highlights the current knowledge of the global epidemiology of TV infection. These include sex differences in the incidence and prevalence of infection, and the potentially important role of female sex hormones, and the menstrual cycle in mediating TV susceptibility and natural history.
WHO has estimated that over half the 248 million new TV infections each year occur in men. By contrast, 89% of prevalent TV cases are found among women. Biological differences between the sexes contribute to these striking differences between men and women.
There has also been an increased understanding of the mechanisms underlying resistance to metronidazole – the current sole drug available to eradicate the organism.
Recent innovations in detection, including the availability of nucleic acid amplification tests (NAATs), have improved our understanding of the natural history of TV infections. These innovations and our increased understanding of this common sexually transmitted infection should help us combat the global epidemic in TV.