Fork of COVID-19 Map (Positive Cases)
This choropleth map displays the relative number of COVID-19 cases per U.S. state using a log-transformed scale of seven-day average positive test results, colored with d3.scaleThreshold and schemeOrRd. Hovering reveals a tooltip with state-level metrics including deaths, tests, and positivity rates. Built with React and D3 v6, the visualization uses d3.geoPath with a geoAlbersUsa projection, TopoJSON for state boundaries, and a d3.Delaunay-based Voronoi overlay for efficient mouse interaction over irregular shapes. The accompanying color legend is rendered using d3 selections.