How Can Progress Toward Ending the Human Immunodeficiency Virus Epidemic in the United States Be Monitored?

Abstract

The plan for Ending the HIV (human immunodeficiency virus) Epidemic (EHE) in the United States aims to reduce new infections by 75% by 2025 and by 90% by 2030. For EHE to be successful, it is important to accurately measure changes in numbers of new HIV infections after 5 and 10 years (to determine whether the EHE goals have been achieved) but also over shorter timescales (to monitor progress and intensify prevention efforts if required). In this viewpoint, we aim to demonstrate why the method used to monitor progress toward the EHE goals must be carefully considered. We briefly describe and discuss different methods to estimate numbers of new HIV infections based on longitudinal cohort studies, cross-sectional incidence surveys, and routine surveillance data. We particularly focus on identifying conditions under which unadjusted and adjusted estimates based on routine surveillance data can be used to estimate changes in new HIV infections.

Keywords: HIV; estimates; incidence surveys; infections; surveillance data.

Figure 1.

Modeling results showing performance of unadjusted diagnoses for estimating incidence reductions over time compared with baseline. A, C, Model-based trends over time in new infections (red lines) and new HIV diagnoses (thick black lines) before and following the introduction of the combination prevention intervention for a single set of fit parameters. B, D, Absolute difference between reductions in cumulative diagnoses and reductions in cumulative infections by change in levels of awareness of living with HIV since 2020, for an intervention program scaling up antiretroviral therapy and preexposure prophylaxis over 1 year starting in 2020, with (A, B) concomitant increases in HIV testing or (C, D) concomitant declines in HIV testing. Modeling results are shown after 2, 5, and 10 years. Numbers are for a modeled population of 7000 men who have sex with men. Middle and line box and whisker represent median, 25th, and 75th percentiles and minimum and maximum values, respectively. Dashed and dotted lines are at ±10 percentage points and ±20 percentage points from the true reduction in new infections, respectively. Abbreviation: HIV, human immunodeficiency virus.

Figure 2.

Modeling results showing performance of adjusted diagnoses and other surveillance markers for estimating incidence reductions. Absolute difference between reductions in diagnoses with evidence of recent infection, diagnoses adjusted for time since infection, diagnoses adjusted for number of tests performed, or the proportion of diagnosed men who are not virally suppressed, and reductions in cumulative infections, across all intervention runs, after 2, 5, or 10 years of a program expanding antiretroviral therapy, preexposure prophylaxis and testing together, with a 1-year scale-up period, starting in 2020. Middle line and box and whisker represent median, 25th, and 75th percentiles and minimum and maximum values, respectively. Dashed and dotted lines are at ±10 pp and ±20 pp from the true reduction in new infections, respectively.