Fig. 2

The case maps and the constructed spatiotemporal transmission networks on (A) January 20, 2022, (B) January 22, 2022, January 25, 2022, and January 28, 2022, and (C) January 31, 2022 in Hong Kong, China. The red map at the bottom of (A) and (C) denotes the case map of the corresponding day. The intensity of the red color indicates the number of the cases. The darker the color on the map, the more cases in the corresponding district. The networks in the blue/green color shown in (B) and at the top of (A) and (C) are the spatiotemporal transmission networks constructed from the case visiting history. The blue color indicates the high transmission intensity while the green color indicates the low intensity. The correspondence between the district code and the district name is provided in the bottom right corner of the figure