Fig. 6.

Spatial distribution of case clusters (A-F) and diffusion dynamics of transmission clusters (A′–F′) for 6 key dates (March 11, March 15, March 19, March 24, March 27, April 4) during the first epidemic wave. Case clusters resulting from the prospective Poisson space-time scan statistics (A–F) are shaded according to their significance level: dark red for statistically significant clusters with alpha = 0.01, light red for statistically significant clusters with alpha = 0.05, and grey for non-significant clusters (p > 0.05). Transmission clusters resulting from the MST-DBSCAN algorithm (A′–F′) are shaded according to their evolution type: emerge (pink), growth (red), steady (green), merge (yellow), move (orange), split (purple), and reduction (blue). Black points in (A) and (A′) represent the 33,651 individuals tested during the study period (January 10 to June 30). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)