This choropleth map visualizes the global prevalence of HIV/AIDS among adults aged 15–49 in 2017. Countries are colored on a yellow-to-red sequential scale based on infection rates, with missing data rendered in grey. The visualization uses React to manage state and D3's `geoNaturalEarth1`, `geoPath`, and `geoGraticule` to render the map projection, graticule, and country boundaries from World Atlas TopoJSON data. The color scale is defined with `scaleSequential` and `interpolateYlOrRd`, mapping numeric prevalence values from a CSV file.