This choropleth map visualizes the global prevalence of HIV/AIDS among adults aged 15-49 in 2017, using a sequential yellow-to-red color scale to indicate infection rates. Countries without data appear in gray. The visualization is built with React and D3 v7, using `geoNaturalEarth1` projection, `geoPath` to render country boundaries, and `geoGraticule` for the latitude/longitude grid. Data comes from IHME, joined to country shapes via ISO numeric codes loaded from a CSV.