Y-Chromosome in Female Sex Workers as a Biomarker of Recent Vaginal Sex and Condom Use with Male Partners in Zimbabwe, A Mixed Methods Study

Abstract

Self-reported data on condom use is questionable and is subject to recall, and social desirability biases. Biomarkers of semen were used to validate self-reported condom use. A secondary data analysis of findings from a respondent driven sampling survey was conducted in 22 sites in Zimbabwe. The secondary data analysis reviewed the outcomes of Y-chromosome testing in female sex workers reporting no condomless sex. Data was collected using a biobehavioral questionnaire investigating sociodemographic data, sexual behavior, experience with HIV testing, PrEP and ART use and common mental disorders. In addition, face to face in-depth interviews were conducted to explore current condom use and identification of facilitators and barriers to use by female sex workers in Zimbabwe. Predictors of condom use were computed using logistic regression analysis in Stata Version 14. Overall, 4444 FSWs took part in the respondent driven sampling survey. About 903 (80%) self-reported consistent condom use, two participants had missing information and were dropped from the analysis. 3541/4444 (80%) self-reported condomless sex. After adjusting for those reporting condom use but with evidence of condomless sex, the number increased to 90%. Of the 901 who reported no condomless sex, 434 (48%) tested positive to Y chromosome DNA. Marital status was a key predictor of Y chromosome among participants testing positive to Y chromosome. Determinants of condom use were years in sex worker, partner type, partner HIV status. Barriers to consistent condom use include partner type, financial empowerment, and refusal to use condoms by partners citing interference with pleasure. To reduce the burden of protection on the female sex worker, the researcher recommends increased male involvement in female sex worker programs. Other recommendations are a combined intervention targeting multiple barriers to condoms use.