Fig. 1: SARS-CoV-2 genomes sequenced from Spain.

a, Distribution of sequenced samples (blue) versus confirmed cases in Spain (gray) by date. Country lockdown measures were in effect from 14 March to 14 May 2020. b, Distribution of the sequenced samples across Spain plotted in Microreact. These data can be explored with more detail in the Microreact webpage (https://microreact.org/showcase) loading the Supplementary Data 1 files. The size of each piechart correlates with the number of sequences collected in the corresponding area. Each color corresponds to a specific Pango lineage, as detailed in Extended Data Fig. 1 (light yellow and green correspond to lineage A, all the others are lineage B). The map image was extracted from the Microreact visualization³⁷. c, Distribution of main SARS-CoV-2 clades during the first stages of the pandemic (before 1 April 2020), in those European countries with more than 50 sequences deposited in GISAID as of 13 November 2020. d, Global ML phylogeny constructed with 32,416 sequences, placement of Spanish samples is indicated in red. e, New and accumulated introductions to Spain. Lower-bound introduction estimates were defined as the probable date of the infection of the first case in a cluster (14 days before symptom onset). f, Estimated international origin of SARS-CoV-2 introductions based on phylogenetic data; in color, those countries with a probable contribution greater than 10%.