Genomic approach to determine sources of neonatal Staphylococcus aureus infection from carriage in The Gambia - Ancillary study to a Randomized Control Trial

Staphylococcus aureus is a major cause of neonatal infections resulting in high morbidity and mortality in The Gambia. These infections are often preceded by carriage, and nasal carriage is a known risk factor for S. aureus infections. To determine if potential sources of newborn S. aureus infections were from carriage and to characterize S. aureus present in different anatomical sites we did whole genome sequencing of 172 isolates. A random selection of mothers and newborns participating in a clinical trial and who tested positive for S. aureus were considered for this study. Sequence data was analysed to determine S. aureus multilocus sequence types and selected antimicrobial and virulence gene profiles.