Analysis of the genetic background of isolates harboring extended-spectrum cephalosporinase-encoding genes showed that four Danish isolates and one,nine,andsix Thai isolates from regional zones 1, 4, and BKK, respectively, clustered in a group
defined by 78% similarity (highlighted in Fig. 3). These isolates showed highly similar antimicrobial susceptibility profiles and harbored the blaCMY-2 gene (Fig. 3). Also, one isolate from BKK harboring a blaCTX-M-15 gene belonged to this PFGE lineage (Fig. 3).TheremainingblaCMY-2-harboringisolates(n3)originating from zone 4 and showing a slightly different antimicrobial resistance profile clustered in a different branch of the dendrogram (Fig. 4).