Fig. 4

Spatial clusters of severe HFMD in Chongqing, China from 2013 to 2018. The space scan proposed by Kulldorff is integrated in SaTScan TM v9.4 (http://www.satscan.org/) and clusters are depicted on the map using the software ArcGIS10.2 (https://www.arcgis.com/features/index.html, ESRI, Inc., Redlands, CA, USA). Note: The most likely cluster was shown in red color on the map, the secondary cluster was in pink color and the 2nd secondary cluster was in orange color. The blue curve on the map represents the trunk of the Yangtze River. The map depicted in Fig. 4 were taken from National Geomatics Center of China. (http://www.ngcc.cn/ngcc/)