Multiple smoothed time-series lines track cumulative COVID-19 deaths per country, with daily death counts plotted on a logarithmic scale. Hovering over any line reveals a tooltip with the country name, total deaths, and date. The chart uses React with D3’s `scaleTime`, `scaleLog`, and `line` generators, while `d3.Delaunay` constructs a Voronoi overlay to capture mouse events for precise line selection. Data comes from the CSSE at Johns Hopkins.