Prevalence of <i>Trichomonas vaginalis</i> infection and protozoan load in South African women: a cross-sectional study.

Abstract

<i>Trichomonas vaginalis</i> is thought to be the most common non-viral sexually transmitted infection worldwide. We investigated the prevalence, risk factors and protozoan load of <i>T. vaginalis</i> infection in South African women. A cross-sectional study of 604 women was conducted at 25 primary healthcare facilities in rural South Africa (Mopani district). <i>T. vaginalis</i> DNA was detected in vaginal and rectal swabs. In univariate and multivariate analyses, the <i>T. vaginalis</i> infection was investigated in relation to demographic characteristics, medical history and behavioural factors. The <i>T. vaginalis</i> load was determined as the logarithm of DNA copies per microlitre sample solution. Collected vaginal and rectal swabs were tested for <i>T. vaginalis</i> DNA. Prevalence of vaginal <i>T. vaginalis</i> was 20% (95% CI 17.0% to 23.4%) and rectal 1.2% (95% CI 0.6% to 2.4%). Most women (66%) with a vaginal infection were asymptomatic. Factors associated with <i>T. vaginalis</i> infection were a relationship status of single (OR 2.4; 95% CI 1.5 to 4.0; p<0.001) and HIV positive infection (OR 1.6; 95% CI 1.0 to 2.6; p=0.041). Women with vaginal <i>T. vaginalis</i> infection were more likely to have concurrent <i>Chlamydia trachomatis</i> rectal infection than those without vaginal infection (12%vs3%; p<0.001; OR 4.1). A higher median <i>T. vaginalis</i> load was observed among women with observed vaginal discharge compared with those without vaginal discharge (p=0.025). Vaginal trichomoniasis is highly prevalent in rural South Africa, especially among single women and those with HIV infection, and often presents without symptoms.