Factors associated with sexually transmitted infections among care-seeking adults in the African Cohort Study

Sexually transmitted infections (STIs) are a major cause of morbidity. Understanding drivers of transmission can inform effective prevention programs. We describe STI prevalence and identify factors associated with STIs in four African countries. The African Cohort Study is an ongoing, prospective cohort in Kenya, Nigeria, Tanzania and Uganda. At enrollment, a physical exam was conducted and STI diagnosis made by a clinician using a syndromic management approach. Multivariable logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) for factors associated with an STI diagnosis. As of June 2020, 3544 participants were enrolled. STI prevalence was 7.7% and did not differ by HIV status (p = 0.30). Prevalence differed by syndrome (3.5% vaginal discharge, 1.5% genital ulcer, 2.1% lower abdominal pain, 0.2% inguinal bubo). The odds of having an STI were higher at all sites compared to Kisumu West, Kenya, and among those with a primary level education or below compared to those with secondary or higher (aOR: 1.77; 95% CI: 1.32-2.38). The odds of an STI diagnosis was higher among participants 18-29 years (aOR: 2.29; 95% CI: 1.35-3.87), females (aOR: 2.64; 95% CI: 1.94-3.59), and those with depression (aOR: 1.78; 95% CI: 1.32-2.38). Among PLWH, similar factors were independently associated with an STI diagnosis. Viral suppression was protective against STIs (aOR: 2.05; 95% CI: 1.32-3.20). Prevalence of STIs varied by site with young people and females most at risk for STIs. Mental health is a potential target area for intervention.