Phylogeographic clustering of Caribbean/Americas epidemic CHIKV strains.

<p>The Bayesian maximum clade credibility (MCC) tree of CHIKV Asian genotype was annotated to reflect the geographic origin of samples collected in the Americas. The CO clade was split into three parts, magnified, and indicated by gray shading: subclade CO1 (right side of the tree), subclade CO2 (left middle panel), and non-CO1/CO2 strains (left lower panel). Sequences from different regions are colored in branches as described in the key. The original countries of infections (either indigenous or travel-related) are depicted with colored ovals next to the complete strain names and described in the key as well.