Ontario’s Public Health Units (PHUs) experienced uneven COVID-19 case surges and vaccination uptake during the pandemic, influenced by geography, demographics, and socioeconomic conditions. Despite widespread vaccination campaigns, certain regions and age groups continued to face disproportionate infection rates and healthcare pressures. This raises critical questions about the effectiveness of vaccination programs, equity in health outcomes, and the ability to predict and manage future waves. Without a data-driven understanding of these patterns, resource allocation and policy responses risk being reactive rather than proactive.