Skin and soft tissue infections (SSTI) are common in Aotearoa/New Zealand (NZ), affecting 29% of children under five years old. Māori and Pasifika children and those living in the most deprived households experience a disproportionately high burden of disease. Children colonised with Staphylococcus aureus have a greater risk of SSTI. This is particularly true for children with a high density of S. aureus in the nose, which researchers use as a proxy for persistent colonisation. The longitudinal nature of Growing Up in New Zealand (GUiNZ) allows us to measure colonisation of the nose, throat, and skin at different time points, providing a measure of recurrent colonisation. This study will investigate the relationship between recurrent colonisation with bacterial organisms (S. aureus, methicillin resistant S. aureus (MRSA), and S. pyogenes) and SSTIs. Children in the GUiNZ cohort provided bacterial swabs from their nose, throat, and skin at the 4.5y and 8y data collection waves and laboratory analyses identified SSTI-associated organisms. We will examine the relationship between sporadic (i.e. colonisation with the organism at 4.5y OR 8y) and recurrent colonisation (i.e. colonisation with the same organism at 4.5y AND 8y) and SSTIs. We will use two SSTI outcome measures: (i) parent report; and (ii) hospital report, combined to give a composite endpoint. We will investigate associations between recurrent bacterial colonisation and SSTI using unadjusted and multivariable logistic regression analyses accounting for known SSTI risk factors. We will also examine the pattern of antibiotic prescriptions dispensed in the community prior to hospital admission with an SSTI. These analyses will identify determinants of recurrent bacterial colonisation and SSTIs in school-aged children and inform interventions to break the bacterial colonisation – SSTI connection.