ACKNOWLEDGEMENTS
We are indebted to all the study participants, who provided tissue samples and swabs used to isolate CRS specific strains of S aureus . We are grateful for the assistance received from staff of the Biomedical Imaging Unit at the Faculty of Medicine, and in particular Mr David Johnston. We would also like to thank Dr David Cleary for his advice and assistance in the bioinformatics approach used in this study. This project was supported by the Royal College of Surgeons of England through the Dr Shapurji H Modi Memorial Research Fellowship, a pump priming grant provided by the Royal College of Surgeons Edinburgh, and a British Rhinological Society research grant. This study was supported by the Southampton National Institute of Health Research (NIHR) Respiratory Biomedical Research Unit and the Southampton NIHR Wellcome Trust Clinical Research Facility.