The Role of Chlamydia trachomatis in High-Risk Human Papillomavirus Persistence Among Female Sex Workers in Nairobi, Kenya

Background: Little is known about risk factors for persistent high-risk human papillomavirus (hrHPV) infection in low-income settings, and prior research has not quantified the relative duration of hrHPV infections stratified by risk factors. We compared the duration of hrHPV infection among female sex workers (FSWs) by exposure to sexually transmitted infections (STIs), using a highly sensitive biomarker assay. Methods: From 2009 to 2011, 350 FSWs enrolled in this longitudinal study. Every 3 months, sociodemographic and sexual behavior data were collected via questionnaire, and APTIMA assays were used to detect the rRNA of Chlamydia trachomatis (CT), Neisseria gonorrhea, Trichomonas vaginalis, Mycoplasma genitalium, and messenger RNA of the E6/E7 oncoproteins expressed by hrHPV. Among 173 FSW who were infected with hrHPV during the observation period, accelerated failure time models estimated time ratios (TRs) for duration of hrHPV infection, comparing FSW infected with STIs at baseline to STI-uninfected FSWs. Results: Median follow-up time was 26.2 months (interquartile range, 18.8-27.5 months). The median duration of hrHPV infection among all FSWs was 9.3 months (95% confidence interval [CI], 9.3-11.5). The duration of hrHPV infection among FSWinfected with CT at baseline was greater than that among FSWs who were uninfected (adjusted TR, 1.7; 95% CI, 1.2-2.6). Among FSWs who were coinfected with hrHPV and CT at baseline, the adjusted TR was 3.4 (95% CI, 2.5-5.4) compared with FSWs infected with hrHPV only. No other STI was associated with hrHPV duration. Conclusions: Recent or concurrent CT infection was associated with prolonged hrHPV infection among a cohort of Nairobi FSWs. Management of CT could reduce risk for hrHPV persistence.