We aim to explore spatial variations in socioeconomic inequalities in self-reported recent HIV testing uptake in sub-Saharan Africa (SSA) at different geographical scales, in order to identify potential geographical hotspots of inequalities. Additionally, to evaluate the potential benefits of HIV testing programs, we assess whether local levels of HIV testing match the local levels of HIV prevalence.

We analyzed data from 25 countries in SSA with Demographic and Health Surveys between 2011 and 2019. We quantified socioeconomic inequalities in self-reported HIV testing in the last 12 months with both the Slope Index of Inequality (SII) and Relative Index of Inequality (RII) in different geographical scales to capture sex-specific within-country spatial variations. We also conducted sampling cluster-level analyses based on the Local Indicator of Spatial Association to consider the autocorrelation in SII and RII across SSA countries. To assess the spatial efficiency of HIV testing programs, we measured the correlation between recent HIV testing uptake and HIV prevalence through Pearson correlation across geographical scales.

We observed pro-rich inequalities on both absolute and relative scales in recent HIV testing in the majority of SSA countries in female and male participants at the national level. We also identified inequalities at subnational levels. Within- and between-country heterogeneities in sex-specific inequalities on both inequality scales and their respective spatial distributions varied depending on the scale used. Clustering of high absolute and relative inequalities were mostly observed in Western and Central Africa with a few regions in Eastern and Southern Africa. Despite significant sex-specific correlations between HIV testing and HIV prevalence in all countries when assessed at the national level, we report an absence of such a correlation at fine scale in 39 of 50 sex-country combinations.

These findings highlight the importance of investigating the spatial variability of various HIV indicators and related inequalities. Results may help local, national and international policymakers to prioritize areas and socioeconomic subgroups in need of HIV testing services. Our results also show the need to monitor efficiency of HIV testing programs in relation to HIV risk at subnational levels as a complementary to national estimates.