Background: Women in Africa disproportionately acquire human immunodeficiency virus type 1 (HIV-1). Understanding which women are most likely to acquire HIV-1 can guide focused prevention with preexposure prophylaxis (PrEP). Our objective was to identify women at the highest risk of HIV-1 and estimate PrEP efficiency at different sensitivity levels.
Methods: Nationally representative data were collected from 2015 through 2019 from 15 population-based household surveys. This analysis included women aged 15-49 who tested HIV-1 seronegative or had recent HIV-1. Least absolute shrinkage and selection operator regression models were fit with 28 variables to predict recent HIV-1. Models were trained on the full population and internally cross-validated. Performance was evaluated using area under the receiver operating characteristic curve (AUC), sensitivity, and number needed to treat (NNT) with PrEP to avert 1 infection.
Results: Among 209 012 participants, 248 had recent HIV-1 infection, representing 118 million women and 402 000 (95% confidence interval [CI], 309 000-495 000) annual infections. Two variables were retained: living in a subnational area with high HIV-1 viremia and having a sexual partner living outside the home. The full-population AUC was 0.80 (95% CI, .76-.84); cross-validated AUC was 0.79 (95% CI, .75-.84). At 33% sensitivity, 130 000 cases could be averted if 7.9 million women were perfectly adherent to PrEP; NNT would be 61. At 67% sensitivity, 260 000 cases could be averted if 25.1 million women were perfectly adherent; NNT would be 96.
Conclusions: This risk assessment tool was generalizable, predictive, and parsimonious with trade-offs between reach and efficiency.
Keywords: Africa; HIV; preexposure prophylaxis; prevention; risk.
© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.