Reviewed by Geeta Sood, MD, ScM, Johns Hopkins University
Bottom line – Single center study showing plasmid transmission within patients and across species that would not have been detected with only clonal surveillance.
This study at a single institution used whole-genome sequencing of 540 clinical and surveillance multi-drug resistant gram-negative isolates over 18 months to identify suspected clonal and plasmid transmissions. These results were then validated with epidemiological linkage. Plasmids that were genetically similar were not identified as separate transmission events if they occurred in the context of clonal transmission. Escherichia coli and Klebsiella pneumoniae were the most common isolates and carbapenemase genes were detected in 27 isolates. One thousand five hundred thirty nine plasmids were detected. There were 38 potential clonal transmissions in 24 clusters identified and 121 potential plasmid transmissions in 24 clusters. Epidemiologic evidence confirmed 19 clonal transmissions in 7 clusters and an additional 12 plasmid transmissions in 8 plasmid clusters. There were 7 cases of within-host transmission of plasmids and 5 cases of between-patient plasmid transmission. Nine plasmid clusters contained multiple species. This study demonstrates multi-layered components to antimicrobial resistance transmission.
Reference:
Sobkowiak A, Schwierzeck V, van Almsick V, Scherff N, Schuler F, Bessonov K, Robertson J, Harmsen D, Mellmann A. The dark matter of bacterial genomic surveillance-antimicrobial resistance plasmid transmissions in the hospital setting. J Clin Microbiol. 2025 May 12:e0012125. doi: 10.1128/jcm.00121-25. Epub ahead of print. PMID: 40353659.