Geospatial Analysis of Time to Human Immunodeficiency Virus (HIV) Diagnosis and Adult HIV Testing Coverage Highlights Areas for Intervention in the US Southeast

Abstract

Background In the U.S., 44% of people with HIV (PWH) live in the Southeastern census region; many PWH remain undiagnosed. Novel strategies to inform testing outreach in rural states with dispersed HIV-epidemics are needed. Methods Alabama state public health HIV testing surveillance data from 2013-2017 were used to estimate time from infection to HIV diagnosis using CD4 T-cell depletion modeling, mapped to county. Diagnostic HIV tests performed 2013-2021 by commercial testing entities were used to estimate HIV tests per 100,000 adults (15-65-year-old), mapped to client ZIP code tabulation area (ZCTA). We then defined testing “cold spots”: those with <10% adults tested plus either (a) within or bordering one of the 13 counties with HIV prevalence greater than 400 cases per 100,000 population or (b) within a county with average time to diagnosis greater than the state average to inform testing outreach. Results Time to HIV diagnosis is a median of 3.7 (IQR 0-9.2) years across Alabama, with a range from 0.06-12.25 years. Approximately 63% of counties (N=42) have a longer time-to-diagnosis compared to national U.S. estimates. 643 ZCTAs tested 17.3% (IQR: 10.3%,25.0%) of the adult population from 2013-2017. To prioritize areas for testing outreach, we generated maps to describe 47 areas of HIV-testing cold spots at the ZCTA level. Conclusions Combining public health surveillance with commercial testing data provides a more nuanced understanding of HIV testing gaps in a state with a rural HIV epidemic and identifies areas to prioritize for testing outreach.