Model-Based Prioritization of Adolescent Girls and Young Women for HIV Prevention Services Based on Data From 13 Sub-Saharan African Countries.

BACKGROUND

Adolescent girls and young women (AGYW) aged 15-24 years are more likely to acquire HIV than their male counterparts, and well-targeted prevention interventions are needed. We developed a method to quantify the risk of HIV acquisition based on individual risk factors and population viral load (PVL) to improve targeting of prevention interventions.

SETTING

This study is based on household health survey data collected in 13 sub-Saharan African countries, 2015-2019.

METHODS

We developed a Bayesian spatial model which jointly estimates district-level PVL and the probability of infection among individual AGYW, aged 15-24 years, based on individual behavioral/demographic risk factors and area-level PVL. The districts (second subnational level) typically comprise the areas of estimation. The model borrows strength across countries by incorporating random effects, which quantify country-level differences in HIV prevalence among AGYW.

RESULTS

The combined survey data provided 52,171 questionnaire responses and blood tests from AGYW, and 280,323 blood samples from all respondents from which PVL was estimated. PVL was-by far-the most important predictor of test positivity [adjusted odds ratio (aOR) = 70.6; 0.95-probability credible interval 20.7-240.5]. Having a partner with HIV increased the odds of testing positive among AGYW who were never (aOR = 12.1; 7.5-19.6) and ever pregnant (aOR = 32.1; 23.7-43.4). The area under the cross-validated receiver-operating characteristic curve for classification of test positivity was 82%.

CONCLUSION

The fitted model provides a statistically principled basis for priority enrollment in HIV prevention interventions of those AGYW most at risk of HIV infection and geographic placement of prevention services.