Open AccessGenomic surveillance, characterization and intervention of a polymicrobial multidrug-resistant outbreak in critical care
Author(s) -
Leah W. Roberts,
Brian Forde,
Trish Hurst,
Weiping Ling,
Graeme R. Nimmo,
Haakon Bergh,
Narelle George,
Krispin Hajkowicz,
John F. McNamara,
Jeffrey Lipman,
Budi Permana,
Mark A. Schembri,
David L. Paterson,
Scott A. Beatson,
Patrick N A Harris
Publication year - 2021
Publication title -
microbial genomics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.476
H-Index - 28
ISSN - 2057-5858
DOI - 10.1099/mgen.0.000530
Subject(s) - outbreak , multilocus sequence typing , acinetobacter baumannii , metagenomics , klebsiella pneumoniae , pseudomonas aeruginosa , biology , microbiology and biotechnology , multiple drug resistance , infection control , whole genome sequencing , antibiotic resistance , intensive care unit , medicine , drug resistance , virology , genotype , genome , intensive care medicine , genetics , gene , antibiotics , bacteria , escherichia coli
Background. Infections caused by carbapenem-resistant Acinetobacter baumannii (CR-Ab) have become increasingly prevalent in clinical settings and often result in significant morbidity and mortality due to their multidrug resistance (MDR). Here we present an integrated whole-genome sequencing (WGS) response to a persistent CR-Ab outbreak in a Brisbane hospital between 2016-2018. Methods . A. baumannii, Klebsiella pneumoniae, Serratia marcescens and Pseudomonas aeruginosa isolates were sequenced using the Illumina platform primarily to establish isolate relationships based on core-genome SNPs, MLST and antimicrobial resistance gene profiles. Representative isolates were selected for PacBio sequencing. Environmental metagenomic sequencing with Illumina was used to detect persistence of the outbreak strain in the hospital. Results. In response to a suspected polymicrobial outbreak between May to August of 2016, 28 CR-Ab (and 21 other MDR Gram-negative bacilli) were collected from Intensive Care Unit and Burns Unit patients and sent for WGS with a 7 day turn-around time in clinical reporting. All CR-Ab were sequence type (ST)1050 (Pasteur ST2) and within 10 SNPs apart, indicative of an ongoing outbreak, and distinct from historical CR-Ab isolates from the same hospital. Possible transmission routes between patients were identified on the basis of CR-Ab and K. pneumoniae SNP profiles. Continued WGS surveillance between 2016 to 2018 enabled suspected outbreak cases to be refuted, but a resurgence of the outbreak CR-Ab mid-2018 in the Burns Unit prompted additional screening. Environmental metagenomic sequencing identified the hospital plumbing as a potential source. Replacement of the plumbing and routine drain maintenance resulted in rapid resolution of the secondary outbreak and significant risk reduction with no discernable transmission in the Burns Unit since. Conclusion. We implemented a comprehensive WGS and metagenomics investigation that resolved a persistent CR-Ab outbreak in a critical care setting.