Genomic investigation of multispecies and multivariant outbreak reveals key role of horizontal plasmid transmission.

Objectives: New Delhi metallo-β-lactamases (NDMs) are major contributors to the spread of carbapenem resistance globally. In Australia, NDMs were previously associated with international travel, but from 2019 we noted increasing incidence of NDM-positive clinical isolates. We investigated the clinical and genomic epidemiology of NDM carriage at a tertiary-care Australian hospital from 2016 to 2021.

Genomic dissection of endemic carbapenem resistance reveals metallo-beta-lactamase dissemination through clonal, plasmid and integron transfer.

Infections caused by metallo-beta-lactamase-producing organisms (MBLs) are a global health threat. Our understanding of transmission dynamics and how MBLs establish endemicity remains limited. We analysed two decades of bla evolution in a hospital using sequence data from 270 clinical and environmental isolates (including 169 completed genomes) and identified the bla gene across 7 Gram-negative genera, 68 bacterial strains and 7 distinct plasmid types.