Recombination analysis of the complete genome of EV-D68. Bootscan analysis (upper panel) and similarity plot (lower panel) were conducted with SimPlot version 3.5.1 (Kimura distance model; window size, 500 bp; step, 20 bp) on a gapless nucleotide alignment, generated with Clustal X version 2.0 (University College Dublin, Dublin, Ireland), with the genome sequence of the EV-D68 strain BCH895A as a query sequence. The red line denotes EV-D68 subclade D1 strain US/KY/14-18953 and the green line denotes EV-D68 clade A strain CA/RESP/10-786. Arrows indicate the gene regions in which potential recombination breakpoints are located.