NEEMA Funded Projects by Topic Area - HIV
NEEMA 2.0 (2019-2024)
Part of the efforts for the President’s initiative to End the HIV Epidemic in America includes responding to each newly diagnosed case of HIV. This project builds on an existing stochastic network model for transmission of HIV among MSM to include interventions that would specifically identify and screen partners of HIV-infected or higher-risk MSM in order to model one approach to a targeted response for individuals. This analysis would support efforts to address the fourth pillar of the EHE plan, “Respond,” to rapidly detect and respond to growing clusters of HIV infections.
Due to significant racial and ethnic disparities in HIV prevalence, there will be differences in the improvement in viral suppression and PrEP coverage needed to achieve the EHE goals for each racial/ethnic group and the overall population. Prior agent-based models have focused on MSM alone and did not address the 19% of new infections that occur in women, many of which are through sex with bisexual MSM. This project will integrate two agent-based network models (for heterosexuals and MSM, respectively) into a single unified population model of HIV transmission; expand those models to include additional ethnic groups (Hispanic/Latinx), and, determine the amount of race/ethnicity-specific increases in viral suppression and PrEP coverage necessary to reach EHE goals over the next 10 years.
Estimating the sexually active adult and adolescent population at a sub-national level (e.g., county) would improve the local understanding of disease burden of STIs. These estimates would also facilitate relative comparisons of syphilis and HIV burden between MSM and other populations. This project will develop state and county-level estimates for the population of men who have sex with women (exclusively), women who have sex with men, and sexually-active adolescent sexual minority males (ASMM), overall and by race/ethnicity. These estimates can then be used to generate estimates of disease rates in the relevant populations.
In the United States, injection is an increasingly common and high-risk route of administration for prescription and illicit opioids as well as other drugs such as methamphetamine. Unsafe injection drug use (IDU) behaviors increase risk for bloodborne infectious diseases such as hepatitis C virus and HIV, making these infectious diseases secondary but deleterious consequences of the opioid crisis for persons who inject drugs (PWID). Due to the stigmatized and illicit nature of non-medical IDU, population-level prevalence is difficult to measure using survey methods typically used to monitor health-related behaviors. Estimation of national IDU prevalence is critical for informing infectious disease prevention efforts among PWID. The current national PWID population size estimate is based on household survey data from 2011 and does not reflect the current opioid and methamphetamine injection. This project will update the PWID prevalence estimates nationally and for specific subpopulations of interest.
PWID are at high risk for multiple blood-borne and sexually transmitted infections including HCV and HIV. National and state-level planning on syringe services programs (SSPs) and medication-assisted treatment (MAT) rely on accurate estimation of PWID population numbers and understanding of how these interventions impact HCV and HIV transmission among PWID. The particular structure of injection networks and sexual networks among PWID leads to heterogeneous risks of infection transmission and acquisition across the PWID population. In addition to syringe services and treatment for underlying opioid use disorder that leads to injection risks, many other preventive modalities are available for both HCV and HIV, including biomedical interventions (e.g. HIV pre-exposure prophylaxis, HIV treatment, HCV treatment); and behavioral interventions (e.g. promoting safer injection practices, condom use.) Different interventions can interact with each other and generate synergistic (or antagonistic) effects on the control of HCV and HIV transmission. What determines the optimal intervention package is unknown. This project will extend the existing agent-based network model of HCV transmission among PWID to: (1) determine the levels of SSP coverage needed to reduce new HIV and HCV infections among PWID by 25%, 50% and 90%, (2) compare the population health and economic impacts of different levels of program coverage for opioid use disorder, (3) identify intervention combinations across the array of different prevention modalities that may produce substantial reductions in HCV and HIV burden among PWID, and (4) compare the cost-effectiveness of different intervention packages.