Abstract
Escherichia coli sequence type 131 (ST131) is a pandemic clone that is evolving rapidly with increasing levels of antimicrobial resistance. Here, we investigated an outbreak of E. coli ST131 producing extended spectrum β-lactamases (ESBLs) in a long-term care facility (LTCF) in Ireland by combining data from this LTCF (n=69) with other Irish (n=35) and global (n=690) ST131 genomes to reconstruct the evolutionary history and understand changes in population structure and genome architecture over time. This required a combination of short- and long-read genome sequencing, de novo assembly, read mapping, ESBL gene screening, plasmid alignment and temporal phylogenetics. We found that Clade C was the most prevalent (686 out of 794 isolates, 86 %) of the three major ST131 clades circulating worldwide (A with fimH41, B with fimH22, C with fimH30), and was associated with the presence of different ESBL alleles, diverse plasmids and transposable elements. Clade C was estimated to have emerged in c. 1985 and subsequently acquired different ESBL gene variants (bla CTX-M-14 vs bla CTX-M-15). An ISEcp1-mediated transposition of the bla CTX-M-15 gene further increased the diversity within Clade C. We discovered a local clonal expansion of a rare C2 lineage (C2_8) with a chromosomal insertion of bla CTX-M-15 at the mppA gene. This was acquired from an IncFIA plasmid. The C2_8 lineage clonally expanded in the Irish LTCF from 2006, displacing the existing C1 strain (C1_10), highlighting the potential for novel ESBL-producing ST131 with a distinct genetic profile to cause outbreaks strongly associated with specific healthcare environments.
Highlights
Escherichia coli is the leading cause of urinary tract infections and bloodstream infections (BSIs) [1, 2], with the number of E. coli BSIs continuing to increase in Europe and the United States since the early 2000s [3,4,5,6,7]
We focused on the genetic profiles of 90 E. coli sequence type 131 (ST131) isolated between 2005 and 2011 in Ireland, of which 69 were from one long-term care facility (LTCF) where an outbreak of ESBL-E
We traced the genomic background of ESBL-E. coli ST131 isolates collected from residents of a LTCF in Ireland where an outbreak was recognised in 2006
Summary
Escherichia coli is the leading cause of urinary tract infections and bloodstream infections (BSIs) [1, 2], with the number of E. coli BSIs continuing to increase in Europe and the United States since the early 2000s [3,4,5,6,7]. This has been associated with the emergence and dissemination of antibioticresistant E. coli producing extended-spectrum β-lactamases (ESBL-E. coli) conferring resistance to many beta-lactam antibiotics, including cephalosporins [6, 7]. Clade C0 has been reported as ancestral and is composed of FQ-
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.