A practical online tool to estimate antiretroviral coverage for HIV infected and susceptible populations needed to reduce local HIV epidemics.

Antoine Chaillon,Nadir Weibel,Davey M Smith,Susan J Little,Martin Hoenigl,Sanjay R Mehta

doi:10.1038/srep28707

Abstract

It remains unclear what proportions of HIV-infected and uninfected people should receive effective antiretroviral therapy (ART) to control local HIV epidemics. We developed a flexible model to evaluate the impact of treatment as prevention (TasP) and pre-exposure prophylaxis (PrEP) on HIV incidence in local communities. We evaluated this tool for determining what TasP and PrEP targets are needed to substantially reduce the HIV epidemic in San Diego, which is predominately comprised of men who have sex with men. By increasing the proportion of HIV-infected individuals on ART from 30% to 50%, 686 new infections would be prevented over five years in San Diego. By providing PrEP to 30% of MSM to the age group that account for 90% of local HIV incident cases (21–52 years), we could prevent 433 infections over five years. When combining these initiatives, a PrEP coverage rate of 40% and TasP coverage rate of 34% would be expected to decrease the number of new infections by over half in one year. This online tool is designed to help local public health planners and policy makers to estimate program outcomes and costs that may lead to better control of their local HIV epidemics.

Highlights

It is becoming increasingly clear that we may have the tools to end the HIV epidemic, especially with broader use of antiretroviral therapy (ART)[1]
This study developed an intuitive and flexible tool based on the main drivers of sexual HIV epidemics to provide targets of treatment as prevention (TasP) and pre-exposure prophylaxis (PrEP) coverage rates needed to reduce HIV incidence
We evaluated this tool in the context of the well-characterized HIV epidemic in San Diego, which is predominantly driven by risk among MSM, similar to many metropolitan areas across the U.S.28

Summary

Introduction

It is becoming increasingly clear that we may have the tools to end the HIV epidemic, especially with broader use of antiretroviral therapy (ART)[1]. Empirical and deterministic models have been developed by several groups to evaluate the impact of voluntary HIV testing and immediate ART8, the impact on HIV prevalence and incidence of interventions that decrease disparities[9] or cost-effectiveness of treatment and prevention[10,11] While these studies are highly relevant to determine the theoretical impact of initiatives, they are complex and less conducive for adjustments for local HIV epidemics, especially when quickly comparing the adjustment of epidemic or initiative parameters to suit local efforts. In this setting, simple mathematical models using empirical parameters, as provided here, may help provide targets of TasP and PrEP coverage rates to reduce HIV incidence in local populations. We believe that such a tool may help to provide estimates of what proportion of HIV-infected and uninfected people in a local population need to be covered with ART (TasP and PrEP) to most efficiently control an epidemic

Objectives

Methods

Results

Conclusion