Core genome SNPs-based phylogenetic tree.

<p>All isolates were clustered into three distinct groups. Countries where the sample collection originated are indicated in parentheses. Concatenated core genome SNPs sequences were aligned and phylogenetic inferences obtained using the maximum-likelihood method within the MEGA 5.1 software. Numbers at the nodes are percentages of bootstrap values obtained by repeating the analysis 1,000 times to generate a majority consensus tree. The scale bar represents a 6% sequence difference.