The role of commercial sex venues in the HIV epidemic among men who have sex with men.

BACKGROUND: Commercial sex venues such as bathhouses and sex clubs have long been considered important facilitators of HIV transmission among men who have sex with men in the United States. Recent probability surveys of commercial-sex-venue patrons in King County, WA that included data on behavior both within and outside these venues provide an empirical basis for the development of mathematical models to estimate the role that commercial sex venues play in the HIV epidemic. METHODS: We constructed deterministic compartmental mathematical models of HIV transmission to estimate both current incidence among King County men who have sex with men and incidence in 5 counterfactual scenarios in which commercial-sex-venues were presumed not to exist. We parameterized the models using a range of values for the proportion of commercial sex venues partnerships replaced in the absence of these venues, and the number of acts of unprotected anal intercourse per other types of partnership. Yearly attributable number was calculated as the difference between incident HIV cases in the main models and each corresponding counterfactual model. We performed extensive sensitivity analyses using Latin hypercube sampling. RESULTS: Replacement of 25% of commercial sex venue partners in the absence of these venues resulted in attributable number values near zero per year. Replacement of 50% or more of commercial sex venue partners resulted in negative yearly attributable numbers, indicating a net increase in incident HIV infections in the absence of these venues. Results of the sensitivity analyses were consistent with the main findings. CONCLUSIONS: Our findings imply that commercial sex venues contribute little to the burden of HIV among men who have sex with men in King County, WA.

A pragmatic approach to monitor and evaluate implementation and impact of differentiated ART delivery for global and national stakeholders.

INTRODUCTION: The World Health Organization's (WHO) recommendation of "Treat All" has accelerated the call for differentiated antiretroviral therapy (ART) delivery, a method of care that efficiently uses limited resources to increase access to HIV treatment. WHO has further recommended that stable individuals on ART receive refills every 3 to 6 months and attend clinical visits every 3 to 6 months. However, there is not yet consensus on how to ensure that the quality of services is maintained as countries strive to meet these standards. This commentary responds to this gap by defining a pragmatic approach to the monitoring and evaluation (M&E) of the scale up of differentiated ART delivery for global and national stakeholders. DISCUSSION: Programme managers need to demonstrate that the scale up of differentiated ART delivery is achieving the desired effectiveness and efficiency outcomes to justify continued support by national and global stakeholders. To achieve this goal, the two existing global WHO HIV treatment indicators of ART retention and viral suppression should be augmented with two broad aggregate measures. The addition of indicators measuring the frequency of (1) clinical and (2) refill visits by PLHIV per year will allow evaluation of the pace of scale up while monitoring its overall effect on the quality and efficiency of services. The combination of these four routinely collected aggregate indicators will also facilitate the comparison of outcomes among facilities, regions or countries implementing different models of ART delivery. Enhanced monitoring or additional assessments will be required to answer other critical questions on the process of implementation, acceptability, effectiveness and efficiency. CONCLUSIONS: These proposed outcomes are useful markers for the effectiveness and efficiency of the health system's attempts to deliver quality treatment to those who need it-and still reserve as much of the available resource pool as possible for other key elements of the HIV response.