Spatial epidemiology is a way of looking at how diseases spread across different places on a map. It tracks where a disease appears and how it moves between locations to help researchers understand how it might spread in the future. Scientists use maps to plot where the disease has been seen, which can show where it has spread from, and how it's changing over time. This helps them understand why diseases might move from one area to another and how the environment or other factors might affect the spread of a disease.