The
presence of a particularly successful plasmid able to appear in
multiple isolates and serovars is worrisome. The remaining four
plasmid types carryingblaCMY-2
were isolated in zone 4 inRatcha-buri Hospital. The presence of multiple plasmid lineages in the
same hospital in a relatively short time period (Table 3) could
indicate the presence of selective pressure forblaCMY-2
. However,
pressure that is selective for other antimicrobial resistance genes
should also be considered, since all plasmids except one carried
genes conferring resistance to additional antimicrobials