A Multispecies Cluster of VIM-1 Carbapenemase-Producing Enterobacterales Linked by a Novel, Highly Conjugative, and Broad-Host-Range IncA Plasmid Forebodes the Reemergence of VIM-1.

ABSTRACT

In this study, we investigated VIM-1-producing Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Citrobacter freundii, and Enterobacter cloacae strains, isolated in 2019 during a period of active surveillance of carbapenem-resistant Enterobacterales in a large university hospital in Italy. VIM-1-producing strains colonized the gut of patients, with up to three different VIM-1-positive bacterial species isolated from a single rectal swab, but also caused bloodstream infection in one colonized patient. In the multispecies cluster, blaVIM-1 was identified in a 5-gene cassette class 1 integron, associated with several genetic determinants, including the blaSHV-12, qnrS1, and mph(A) genes, located on a highly conjugative and broad-host-range IncA plasmid. The characteristics and origin of this IncA plasmid were studied.