Outbreak of New Delhi Metallo-Beta-lactamase Carbapenemase Producing Enterobacterales on a bone marrow transplant unit: Role of the environment

Katherine Prescott; Harriet Billam; Carl Yates; Mitch Clarke; Ros Montgomery; Karren Staniforth; Natalie Vaughan; Tim Boswell; Nikunj Mahida

doi:10.1016/j.infpip.2021.100125

Outbreak of New Delhi Metallo-Beta-lactamase Carbapenemase Producing Enterobacterales on a bone marrow transplant unit: Role of the environment

Infect Prev Pract. 2021 Feb 16;3(2):100125. doi: 10.1016/j.infpip.2021.100125. eCollection 2021 Jun.

Authors

Katherine Prescott¹, Harriet Billam¹, Carl Yates², Mitch Clarke², Ros Montgomery², Karren Staniforth², Natalie Vaughan², Tim Boswell¹, Nikunj Mahida¹

Affiliations

¹ Department of Microbiology, Nottingham University Hospitals NHS Trust, England, UK.
² Infection Prevention & Control, Nottingham University Hospitals NHS Trust, England, UK.

Abstract

Background: Carbapenemase Producing Enterobacterales (CPE) are a global health concern. Nosocomial outbreaks have been reported globally with patient-to-patient transmission felt to be the most frequent route of cross-transmission.

Aim: To describe the investigation and control of an outbreak of healthcare-associated New Delhi Metallo-beta-lactamase (NDM) CPE on a haematology ward, over 2 months.

Methods: Four patients acquired CPE; all had gastrointestinal tract colonisation with two subsequently developing bacteraemias. The outbreak team performed a retrospective review, prospective case finding and environmental sampling using swabs, settle plates, air and water sampling. Immediate control measures were implemented including appropriate isolation of cases and additional ward cleaning with chlorine disinfectant, ultra-violet light decontamination and hydrogen peroxide.

Findings: Following two cases of nosocomial acquired CPE prospective case finding identified two further cases. 4.6% of the initial environmental samples were positive for CPE including from waste water sites, the ward sluice and the ward kitchen. Three of the four CPE isolates were identical on pulse field gel electrophoresis (PFGE) typing. Detection of the CPE from the ward kitchen environmental samples suggests a possible role for cross transmission.

Conclusion: This is the first CPE outbreak report to highlight the role of a ward kitchen as a possible source of cross-transmission. In view of this we suggest ward kitchens are reviewed and investigated in nosocomial CPE outbreaks.

Keywords: Carbapenemase Producing Enterobacterales (CPE); Environment; Kitchen; New Delhi Metallo-Beta-lactamase (NDM); Outbreak.