A hierarchical tree chart visualizes the structure of COVID-19, its variants, symptoms, and associated medications. The interactive SVG animation, rendered with D3.js, displays a root square node for COVID-19, branching into circular nodes for variants like Alpha and Delta, each with prevalence percentages and linked medications, then cascading to symptom sub-nodes with their own frequency percentages. The visualization uses D3's force simulation to dynamically position the tree nodes, with custom colors and node types distinguishing different data levels.