Fig 1.

Dendrogram showing the PFGE profiles of the 803 GAS isolates. The dendrogram was constructed using the unweighted-pair group with arithmetic mean (UPGMA) method. Dice coefficients (percentages) are indicated in the scale above the dendrogram. For each PFGE cluster, a triangle proportional to the number of isolates is shown in the dendrogram. The clusters are designated by letters, with major clusters (n ≥ 10) identified by uppercase letters and minor PFGE clusters (10 > n ≥ 5) identified by lowercase letters. The subscript numbers indicate the number of isolates included in the cluster.