Characterization of a colistin-resistant Salmonella enterica 4, [5], 12:i:- harbouring mcr-3.2 on a variant IncHI-2 plasmid identified in Canada

We have identified a Salmonella enterica serotype 4,[5], 12:i:- containing a mcr-3.2 in a patient who travelled to Thailand 1 month prior to the identification of it in Canada. The isolate was multidrug resistant, but remained susceptible to the carbapenems, amikacin and piperacillin/tazobactam. The mcr-3.2 was carried on a 261 Kb variant of the IncHI2 pWJ1. This report provides further evidence of the emergence of a ST34 colistin-resistant clone.