Data on whole-genome sequencing are insufficient to rule out patient-to-patient transmission as a significant source of staphylococcus aureus acquisition in an intensive care unit

摘要

The recent publication by Price et al [1] uses novel methods to illustrate the complex dynamics involved in nosocomial transmission of Staphylo-coccus aureus through the use of whole-genome sequencing. However, the claim that patient-to-patient transmission is a rare occurrence is not well justified by the presented data. The authors report 7 of 37 (18.7%) patient-to patient transmission events based on whole-genome sequencing of isolates with available spa typing results. Our calculated confidence intervals for these proportions range from 6.3% to 31.5%. Furthermore, if only methicillin-resistant S. aureus transmission events in isolates with available spa types are analyzed, the proportion increases to 5 of 14 (35.7%), with confidence intervals of 10.6%-60.8%. These numbers are more consistent with existing data on rates of horizontal transmission of S. aureus.