Genomic Surveillance of Methicillin-resistant Staphylococcus aureus: A Mathematical Early Modeling Study of Cost-effectiveness.

Amy Dymond,Francesc Coll,Heather Davies,Nicholas M Brown,Sharon J Peacock,Stuart Mealing,Vicki Pollit

doi:10.1093/cid/ciz480

Abstract

BackgroundGenomic surveillance of methicillin-resistant Staphylococcus aureus (MRSA) identifies unsuspected transmission events and outbreaks. Used proactively, this could direct early and highly targeted infection control interventions to prevent ongoing spread. Here, we evaluated the cost-effectiveness of this intervention in a model that compared whole-genome sequencing plus current practice versus current practice alone.MethodsA UK cost-effectiveness study was conducted using an early model built from the perspective of the National Health Service and personal social services. The effectiveness of sequencing was based on the relative reduction in total MRSA acquisitions in a cohort of hospitalized patients in the year following their index admissions. A sensitivity analysis was used to illustrate and assess the level of confidence associated with the conclusions of our economic evaluation.ResultsA cohort of 65 000 patients were run through the model. Assuming that sequencing would result in a 90% reduction in MRSA acquisition, 290 new MRSA cases were avoided. This gave an absolute reduction of 28.8% and avoidance of 2 MRSA-related deaths. Base case results indicated that the use of routine, proactive MRSA sequencing would be associated with estimated cost savings of over £728 290 per annual hospitalized cohort. The impact in total quality-adjusted life years (QALYs) was relatively modest, with sequencing leading to an additional 14.28 QALYs gained. Results were most sensitive to changes in the probability of a MRSA-negative patient acquiring MRSA during their hospital admission.ConclusionsWe showed that proactive genomic surveillance of MRSA is likely to be cost-effective. Further evaluation is required in the context of a prospective study.

Highlights

We showed that proactive genomic surveillance of methicillin-resistant Staphylococcus aureus (MRSA) is likely to be cost-effective
In the case of bacterial pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA), an assessment may incorporate routine data generated by the microbiology laboratory on antibiotic resistance
Under the assumption that data from whole-genome sequencing would result in a 90% reduction in MRSA acquisition, 290 new MRSA cases were avoided

Summary

Methods

A UK cost-effectiveness study was conducted using an early model built from the perspective of the National Health Service and personal social services. The effectiveness of sequencing was based on the relative reduction in total MRSA acquisitions in a cohort of hospitalized patients in the year following their index admissions. A decision tree framework (Figure 1) was used to estimate the reduction in the total number of MRSA acquisitions (including any subsequent infection) and, the cost-effectiveness of whole-genome sequencing over 1 year, based on an annual cohort of newly admitted, hospitalized patients. The model was built from the National Health Service (NHS) and personal social services perspective, which is consistent with the National Institute for Health and Care Excellence reference case [9]. Per-patient quality-adjusted life years (QALYs) were generated, and the primary outcome of the model was the incremental cost per QALY gained

Results

Discussion

Conclusion