Rapid control of an outbreak of carbapenemase-producing enterobacterales in a recently built, single-bedded, specialist cardiothoracic hospital in England

Background: Increasing global prevalence of antibiotic-resistant carbapenemase-producing Enterobacterales (CPE) is a major concern. An outbreak occurred in a recently built, single-bedded cardiothoracic hospital, where infection control is crucial to protect vulnerable patients. Aim: The aim of this study was to describe transmission dynamics of CPE in a modern hospital and subsequent control measures used to contain the outbreak. Methods: A case was defined as a polymerase chain reaction–positive CPE (KPC-2) inpatient from June 2024 onwards. Admission and weekly rectal screening were conducted for patients on affected wards. Screening positivity rates were calculated before and after control measure implementation. Thirty-five environmental samples were collected and tested. Whole-genome sequencing (WGS) of clinical and environmental sample isolates was performed to understand relatedness. In-hospital movements of cases were plotted to identify common locations. Findings: Thirty-four cases were identified, which were related on WGS, indicating in-hospital transmission. Four environmental samples were CPE-positive; only one sample (from a floor scrubber) was distantly related to the clinical samples. No common locations among cases were identified. Control measures included increased screening, pausing elective surgery, cohorting cases, ‘double’ cleaning, suspending floor scrubber use, and contact precautions. Screening positivity dropped from 11.9% to 0.4% after control measure implementation. Conclusion: CPE spread rapidly across multiple areas. Comprehensive control measures contained the outbreak. A definitive link between clinical and environmental isolates was not found but not discounted. With rising CPE prevalence, our findings highlight the need for a review of screening guidelines, as well as strict infection control, even in state-of-the-art hospitals, to prevent future outbreaks.