Abstract

Background: Daily pre-exposure prophylaxis (PrEP) and treatment-as-prevention (TasP) reduce HIV acquisition and transmission risk, respectively. With a 2015 HIV prevalence of 17%, female sex workers (FSW) are a key group for HIV prevention in Cotonou, Benin. A demonstration study (2015-2017) assessed the feasibility of TasP and PrEP among FSW. We aimed to assess the population-level impact of the study and various extended and scaled-up PrEP and TasP interventions. Methods: We developed a dynamic HIV transmission model, featuring PrEP, and ART among FSW, clients and the low-risk population, parameterised with the demonstration study data and historical demographic, behavioural, epidemiological and intervention data from Cotonou. The model was calibrated to HIV prevalence, ART coverage, and demonstration study data, reflecting observed lower PrEP uptake, adherence and retention compared to TasP. We modelled the two-year study and several twenty-year intervention scenarios, varying coverage and adherence. We estimated the median (2.5th-97.5th percentile uncertainty interval (95%UI)) percentage and number of incident HIV infections averted comparing the intervention and counterfactual (2017 coverages: 0% PrEP, 49% ART) scenarios. Findings: The two-year study (2017 coverages: 9% PrEP, 83% ART) prevented an estimated 8% (95%UI 6-11) and 5% (2-9) infections among FSW over two and twenty years, respectively, compared to 16% (9-28) and 7% (3-12) among clients, and 6% (3-11) and 4% (2-8) overall. Twenty-year PrEP and TasP scale-ups (2035 coverages: 47% PrEP, 88% ART) prevented 23% (18-28) and 15% (9-23) infections among FSW respectively, and 5% (3-9) and 14% (8-25) overall. Compared to TasP scale-up alone, scaling up PrEP and TasP together prevented 107% and 29% more infections among FSW and overall, respectively. PrEP impact doubled when assuming perfect adherence. Interpretation: The demonstration study had a modest impact, mostly due to TasP. Increasing PrEP adherence and coverage improves impact substantially among FSW, but little in the overall population. TasP should be offered in future prevention packages. Funding Statement: This study was funded by the Bill and Melinda Gates Foundation (grant no. OPP1098973). Complementary funding was provided by the Canadian Institutes of Health Research (grant numbers ROH-115205 and FDN-143218). Truvada for pre-exposure prophylaxis was provided free of charge by Gilead Sciences, Inc. Studentship funding was provided by the United Kingdom Medical Research Council. KM and MCB acknowledge partial funding from the HPTN modelling centre, which is funded by the U.S. National Institutes of Health (NIH UM1 AI068617) through HPTN. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: The authors received approval from the Imperial College Research Ethics Committee (ICREC reference: 18IC4641) to carry out our analysis.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call