2.1 Study setting and ethics statement
The P. aeruginosa AUST-03 (ST 242) strains investigated were isolated from two CF patients attending clinics at a public tertiary academic hospital in Johannesburg, South Africa. The two CF patients (P2 and P4) were part of a study that recruited 22 CF patients at two public academic hospitals in Gauteng, South Africa over the period May 2019 to February 2020. The study was granted ethical approval by the University of the Witwatersrand Human Research Ethics Committee (Reference number: M1811104) and by the University of Pretoria, Faculty of Health Sciences, Research Ethics Committee (Reference number: 466/2018). Sputum specimens were obtained from the CF patients following the provision of written informed assent and consent from the CF patients and their parents, respectively.