Health and Economic Impacts of an HIV Intervention in Out of Treatment Substance Abusers: Evidence from a Dynamic Model

AbstractIntroduction. A community-based intervention program found that the high-risk target population interacts with its surrounding community as a source of drugs and prostitution, creating a measure of co-dependence in the health status of each group. Methodology. The intervention collected extensive data on sexual and drug use practices in the target population. A dynamic compartment model estimates the epidemiological impact of the intervention, which serves as the basis for the economic assessment comparing intervention costs and lifetime HIV treatment costs. Results. Approximately 2/3 of the new infections arise in the surrounding community. Intervention spillover benefits in the surrounding community are sufficient to make the intervention cost-saving in the first year—a savings of ∼$534,000. Conclusions. Conducting the intervention results in health benefits and cost-savings not only for the risk group, but for the entire community in which it resides. Quantifying the spillovers is vital to policymakers attempting to allocate scarce public health resources.