HIV Transmission among Men who have Sex with Men (MSM) in the United States and Peru: Insights from Dynamic Demographic Network Models

Abstract: Recent discoveries have led to renewed hope for making major inroads into HIV epidemics, including pre-exposure prophylaxis, early treatment as prevention, and more sensitive HIV tests.  The relative cost-effectiveness of these interventions will depend on the contexts in which transmission events are currently occurring, which is not well understood.  In this work, we seek to estimate the proportions of transmissions occurring in main vs. casual partnerships, and by the sexual role, infection stage, and testing and treatment history of the infected partner, for men who have sex with men (MSM) in the US and Peru. We use dynamic, stochastic models based in exponential random graph models (ERGMs), obtaining inputs from multiple large-scale MSM surveys. Parallel main partnership and casual sexual networks are simulated. We implement two model variants differing in assumptions about acute infectiousness, and assessed sensitivity to other key inputs. We discuss our results in the context of existing estimates, and their implications for prevention strategies, as well as highlight additional ongoing methodological work to improve our work.

Mis à jour le 06/02/2014