This choropleth map of the United States visualizes Zika virus case counts by state, colored with a pink-to-green interpolated scale. As the page loads, a CSV of 2016 Zika cases is loaded and joined to the state geometries. Each state is rendered as an SVG path and colored according to its case count, with hover interactions that trigger a dark tooltip displaying the state name, low, average, and high case values. The map also includes Alaska and Hawaii insets, and the animation effect is provided by the hover opacity change.