Composite tree of 7th pandemic V. cholerae isolates. Isolates were separated into six groups according to Single Nucleotide Polymorphism (SNP) typing. Isolates with identical SNP profiles were further separated using Multilocus Variable number tandem repeat Analysis (MLVA). A minimum spanning tree (MST) was constructed for each group and combined with the original parsimony tree. Numbers at the node of each between groups indicate the number of SNP differences, whereas numbers at the node of each branch within a group indicate the number of VNTR differences between isolates.