Study Population Characteristics.

1Sex was identified for cases only.
2With or without bacteremia.
3Included in Other: sepsis (7), osteomyelitis or septic arthritis (6), sinusitis (2), otitis (18), cellulitis or abscess (5), UTI (1).
4Race/ethnicity data based on chart abstracted medical records for cases and matched to newborn blood spot repository data for controls.
The Surveillance Cohort was based on all cases of IPD where an nDBS was identified. The Genotype Cohort was defined by samples with amplified genomic DNA of adequate quality for genotyping. The Analysis Cohort was defined by removing all outlier EA samples that STRUCTURE identified as having >10% African ancestry.