The implementation, impact and effectiveness of surveillance systems on the prevention and transmission of carbapenemase-producing organisms

Henderson, Jennifer

Abstract

Carbapenems are broad spectrum antibiotics often reserved for the critically ill. Their increased and, often, inappropriate use, has led to the development of resistance, through acquisition of carbapenemase enzymes. There are five carbapenemases that predominate worldwide (the “big five”): VIM, NDM, KPC, OXA-48 and IMP. However, the true prevalence of carbapenemases is unknown. Therefore, prompt detection, targeted screening, effective control measures and surveillance are required to reduce further transmission of these multi-drug resistant organisms. Each of these were investigated as part of this project.

A systematic review was performed to determine how hospitals in England were implementing the Public Health England (PHE) toolkit for the detection, management and control of Enterobacteriaceae. Following this, carbapenemase prevalence across Barts Health NHS Trust (BHT) was determined by conducting a point prevalence (inpatient) study and a community study, using a published PCR assay that detects the “big five” enzymes. Isolates from these studies and various outbreaks were then investigated by whole genome sequencing. Finally, the value of sequential screening was assessed by reviewing carbapenemase screening data.

The systematic review identified five hospitals which had partially implemented the PHE toolkit, with prior hospitalisation deemed a common risk factor for carbapenemase carriage at these sites and at BHT. The “big five” PCR identified an inpatient carbapenemase prevalence of 3.1% and a community prevalence of 0.5%. Previous hospitalisation was also a notable risk factor at BHT. Whole genome sequencing identified an OXA-48-harbouring IncL/M plasmid among the outbreak isolates, with Klebsiella pneumoniae ST17 also implicated.

The PHE toolkit, as it stands, is costly and impractical for full implementation. Determining the prevalence and high-risk groups at BHT enabled targeted screening for carbapenemase producing organisms. Therefore, it is recommended that all Trusts perform a point prevalence study.

• Thesis Type: Thesis
• Deposit Date: Jun 30, 2020
• Publicly Available Date: Jan 20, 2021
• Public URL: https://uwe-repository.worktribe.com/output/6093082
• Award Date: Jan 20, 2021