This visualization maps vaccine-preventable disease outbreaks across the United States, displaying each incident as a circle on a geographic canvas. The size and color of the circles encode the number of cases and fatalities, respectively, while the chart includes a timeline of outbreak dates. The code uses the `d3.geoPath` projection to render the U.S. map and employs JavaScript canvas drawing for the points. Data is loaded from an embedded CSV array, with each outbreak’s location, date, case count, and fatality count parsed from the text file.