Résumé
Background Around 30% of humans carry Staphylococcus aureus in their nose. S. aureus is an important cause of disease, and carriers are at greater risk of bacteraemia than non-carriers. Why some people carry S. aureus while others never do is not well understood, but is likely to be a complex trait influenced by multiple factors. The CARRIAGE study cohort was established to investigate the determinants of persistent nasal colonisation of S. aureus . Methods Healthy participants were recruited from three nation-wide blood donor cohorts in England, and consented online. Participants were asked to take weekly nasal swabs for up to three consecutive weeks and return them by post. Nasal swabs were processed to determine if they contained S. aureus by microbiological culture and the liquid the swabs were transported in was stored at -70ºC. Results At the end of recruitment in November 2023, 24,264 participants had been recruited. The median age was 55 years (range 19 to 85 years) and 12,981 (53.5%) were female. 20,441 (84.2%) participants provided at least one nasal swab, with 19,105 (78.7%) providing all three nasal swabs. Multidimensional information on participants -- including epidemiological and microbiological exposures, host genomics and other molecular profiling -- is available for all or sizeable subsets of participants. Linkage to routine e-health records has been achieved for most participants. Most participants have indicated they are happy to be contacted for follow up studies. Conclusions The CARRIAGE study cohort is well-placed to investigate determinants of S. aureus colonisation, and for the wider understanding of the biology of the nasal microbiome.