Mrs. Megan Gritt1, Ms. Denise Del Rosario-Kelly1, Ms. Jaimie Yamada1, Ms. Pauline Bass1, Associate Professor Andrew Stewardson1,2
1Alfred Health, Melbourne, Australia, 2Monash University, Melbourne, Australia
Biography:
Megan is an Infection Prevention Nurse Consultant at Alfred Health. She has a background in Infectious Diseases and is working towards a Masters of Public Health and Tropical Medicine, with an interest in antimicrobial resistance and emerging public health threats.
Abstract:
Introduction
Since 2016, Victorian Department of Health guidance on carbapenemase-producing Enterobacterales (CPE) has defined a Transmission Risk Area (TRA) as a geographic area (e.g. ward) and timeframe where CPE transmission occurred. Patients admitted to a TRA for ≥24 hours are ‘ward contacts’ and should be screened for CPE colonisation. We assessed the frequency of case detection of this approach.
Method
We reviewed all TRAs at our health service from 2016 until June 2024. Ward contact identification and screening occurred prospectively during this period. We compiled the total number of ward contacts who provided a rectal swab for CPE screening, and the results of these tests. For CPE-positive ward contacts, routine genomic analysis by the Victorian Public Health Laboratory identified whether the bacterial isolate or carbapenemase gene were closely related to the TRA-specific outbreak isolate.
Results
There have been 30 TRAs at our health service since 2016, resulting in 8464 ward contacts (35–1018 contacts per TRA). Of these contacts, 4154 (49%) were screened for CPE colonisation, and 16 (0.5%) were CPE-positive. Of these 16 CPE-positive ward contacts, five (31%) had closely related bacterial isolates with the same CPE gene, eight (50%) had the same CPE gene but unrelated bacterial isolate, and 3 (19%) had different gene and isolate from the respective TRA.
Conclusion
A very small percentage of TRA ward contacts screened for CPE colonisation test positive for the outbreak isolate. Considering the costs, service impact, and patient experience, a risk-stratified approach may be more appropriate.