Two carbapenemase-producing Enterobacteriaceae outbreaks detected retrospectively by whole-genome sequencing at an Australian tertiary hospital

Alexandra Marmor; Kathryn Daveson; David Harley; Nicholas Coatsworth; Karina Kennedy

doi:10.1016/j.idh.2019.08.005

Two carbapenemase-producing Enterobacteriaceae outbreaks detected retrospectively by whole-genome sequencing at an Australian tertiary hospital

Infect Dis Health. 2020 Feb;25(1):30-33. doi: 10.1016/j.idh.2019.08.005. Epub 2019 Oct 11.

Authors

Alexandra Marmor¹, Kathryn Daveson², David Harley³, Nicholas Coatsworth⁴, Karina Kennedy⁵

Affiliations

¹ Australian National University, Canberra, 2600, Australia. Electronic address: Alexandra.Marmor@anu.edu.au.
² Department of Infectious Diseases and Microbiology, the Canberra Hospital, Canberra, 2605, Australia; Australian National University, Canberra, 2600, Australia. Electronic address: Kathryn.Daveson@act.gov.au.
³ Queensland Centre for Intellectual and Developmental Disability, Mater Research Institute, University of Queensland, South Brisbane, 4101, Australia; Australian National University, Canberra, 2600, Australia. Electronic address: d.harley@uq.edu.au.
⁴ Department of Infectious Diseases and Microbiology, the Canberra Hospital, Canberra, 2605, Australia; Australian National University, Canberra, 2600, Australia. Electronic address: Nicholas.Coatsworth@act.gov.au.
⁵ Department of Infectious Diseases and Microbiology, the Canberra Hospital, Canberra, 2605, Australia; Australian National University, Canberra, 2600, Australia. Electronic address: Karina.Kennedy@act.gov.au.

PMID: 31611185
DOI: 10.1016/j.idh.2019.08.005

Abstract

In 2014, two genetically-linked cases of carbapenemase-producing Enterobacteriaceae (CPE) were detected at the Canberra Hospital (TCH), prompting an investigation and response that appeared to contain transmission. We report a 2017 retrospective investigation into cases of CPE in the Australian Capital Territory (ACT) that aimed to identify clusters and transmission mechanisms. Cases detected between 2012 and 2016 were identified from the hospital laboratory information system. Whole-genome sequencing (WGS) was performed retrospectively on stored isolates. Seventy-two cases were identified, with nearly 90% of isolates containing bla_IMP genes. Using multilocus sequence type (ST) data, we identified two small outbreaks of CPE containing bla_IMP-4 (Enterobacter cloacae complex ST24, n = 7; Citrobacter freundii ST8, n = 10), each spanning over three years. Epidemiological and environmental evidence implicate environmental reservoirs and carriers undetected by routine infection prevention and control investigations.

Keywords: Carbapenemase-producing Enterobacteriaceae; Disease outbreaks; Infection control; Multilocus sequence typing; Whole-genome sequencing.

Publication types

Letter
Research Support, Non-U.S. Gov't

MeSH terms

Australian Capital Territory / epidemiology
Carbapenem-Resistant Enterobacteriaceae / classification
Carbapenem-Resistant Enterobacteriaceae / genetics*
Cross Infection / epidemiology*
Cross Infection / microbiology*
Disease Outbreaks*
Enterobacteriaceae Infections / epidemiology*
Enterobacteriaceae Infections / microbiology*
Genome, Bacterial*
Humans
Phylogeny
Whole Genome Sequencing