Fig. 2

Geographical clustering and classification of the twelve epidemic regions of DENV-1 worldwide by countries/areas at the subgenotype level. a Global distribution of the twelve epidemic regions of DENV-1. The pies are sized to indicate the number of strains and the slices are colored by subgenotypes. WAFR, West African Region; RSR, Red Sea Region; SWIO, Southwest Indian Ocean; SASC, South Asia Subcontinent; GMS-China, Great Mekong Subregion-China; SEA, Southeast Asia; PHI, Philippines; TWP, Tropical Western Pacific; OCE, Oceania; CNA, Central North America; CAR, Caribbean; SA, South America. b Left panel: heatmap of distribution of subgenotypes of DENV-1 represented by countries/areas in the defined 12 epidemic regions, and the 32 countries/areas recorded with more than 10 strains subject to the preliminary hierarchical geographical clustering using partitioning around medoid (PAM) in Additional file 1: Fig. S-E3 highlighted in bold fonts. Right panel: the proportion of involving epidemic regions counted by the number of strains in each subgenotypes of DENV-1