Combination HIV prevention for female sex workers: what is the evidence?

Abstract

Sex work occurs in many forms and sex workers of all genders have been affected by HIV epidemics worldwide. The determinants of HIV risk associated with sex work occur at several levels, including individual biological and behavioural, dyadic and network, and community and social environmental levels. Evidence indicates that effective HIV prevention packages for sex workers should include combinations of biomedical, behavioural, and structural interventions tailored to local contexts, and be led and implemented by sex worker communities. A model simulation based on the South African heterosexual epidemic suggests that condom promotion and distribution programmes in South Africa have already reduced HIV incidence in sex workers and their clients by more than 70%. Under optimistic model assumptions, oral pre-exposure prophylaxis together with test and treat programmes could further reduce HIV incidence in South African sex workers and their clients by up to 40% over a 10-year period. Combining these biomedical approaches with a prevention package, including behavioural and structural components as part of a community-driven approach, will help to reduce HIV infection in sex workers in different settings worldwide.

Figure 1:

Framework for combination prevention: levels of risk and prevention interventions

Figure 2:. Percentage reduction in new HIV infections in sex workers and clients from 2015 to 2025

Percentage reductions in clients are calculated only for infections acquired during commercial sex (excluding infections acquired from non-commercial sex partners). Box-and-whisker plots represent minimum, 25th percentile, median, 75th percentile, and maximum values from the 1000 parameter values in the uncertainty analysis. PrEP=pre-exposure prophylaxis. VM=vaginal microbicide.

Figure 3:. Effect of uptake and efficacy on percentage reduction in new HIV infections from 2015 to 2025

(A) Reduction in incidence in sex workers if only PrEP is provided to sex workers. (B) Reduction in incidence in clients if test and treat interventions are introduced in sex workers. Percentage reductions in clients are calculated only for infections acquired during commercial sex (excluding infections acquired from non-commercial sex partners). Contour plots represent the expected reductions in new HIV infections at different uptake and efficacy levels. PrEP=pre-exposure prophylaxis.