Dr Mark Garvey1, Dr Martyn Wilkinson1, Peter Francis Davis Liquorish Wrightson1, Alyson Gardiner1, Prof Alan McNally2, Dr Rob Moran2, Dr Elisabeth Holden1
1University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom, 2Institute of Microbiology and Infection, School of Medical and Dental Sciences, The University of Birmingham, Birmingham, United Kingdom
Biography:
Mark is a Consultant Clinical Scientist, Director of the Hospital Infection Research Laboratory and the Clinical Director of Infection Prevention and Control at University Hospitals Birmingham NHS Foundation Trust. Mark has >80 peer reviewed journal articles and has given >100 national/international presentations in the field of Infection Prevention and Control.
Abstract:
Background
CPEs pose a significant challenge in hospitals globally. Plasmids carrying carbapenemase genes can transfer between bacteria, playing a major role in transmission and persistence of carbapenem resistance within healthcare. We report a large plasmid-mediated CPE outbreak, and associated environmental control measures, within the Liver speciality at Queen Elizabeth Hospital Birmingham (QEHB).
Methods
At QEHB, to complement standard surveillance, since 2023 CPE isolates have undergone Oxford Nanopore sequencing. Routine hospital environmental disinfection is performed using a chlorine-based detergent. From 1st July 2024 to present, peracetic acid was employed as an alternative cleaning agent exclusively within the Liver speciality. A segmented Poisson regression model was used to analyse changes in monthly CPE numbers over time.
Results
Between April 2015 and June 2024, 163 CPE isolates were identified in QEHB’s Liver patient population, with 30% all-cause mortality observed. Sequencing identified a hospital specific N-type plasmid lineage, pQEB1, carrying several antibiotic resistance genes, including the carbapenemase gene blaKPC-2. Multiple infection control interventions have been put in place to limit the spread of pQEB1. The most successful intervention to date appears to have been introduction of a peracetic acid cleaning product, with the statistical model supporting a subsequent significant reduction in CPEs (p <0.004).
Conclusion
Generating complete plasmid sequences has provided insight into the epidemiology/evolutionary biology of pQEB1, facilitating outbreak detection and targeted interventions. Trialling of a peracetic acid agent for environmental disinfection was associated with a decrease in CPE numbers during an extensive plasmid-mediated outbreak in a high-risk clinical speciality.