A Comparison of Clinical, Neonatal, and Maternal Factors Between Early- and Late-Onset Group B Streptococcal Disease

Universal group B streptococcus (GBS) screening in pregnant people and maternal antibiotic prophylaxis have reduced the incidence of early-onset group B streptococcus (EOGBS) infection. Despite a lower incidence, there is still a high risk of morbidity and mortality without treatment, and there is limited knowledge about late-onset group B streptococcus (LOGBS) infection. Using statewide neonatal sepsis surveillance and hospital admission data, this study describes factors associated with EOGBS and LOGBS.

This retrospective cohort study combined statewide surveillance data for infants with GBS through Active Bacterial Core surveillance (ABCs) data between 2006 and 2020. Cases were defined as EOGBS (>7 days of age) or LOGBS (7-89 days of age). Chi-square tests and the Mann-Whitney test were used for statistical analysis.

Of the 322 identified cases, 106 (32.9%) were EOGBS, and 216 (67.1%) were LOGBS. LOGBS had a higher rate of meningitis (n = 65, 30.1%) compared to EOGBS (n = 11, 10.4%) (p > 0.001) and had a higher percentage of diagnosis via cerebrospinal fluid (CSF) (n = 51, 23.6%) compared to EOGBS (n = 5, 4.7%; p < 0.001). LOGBS were more likely to receive maternal antibiotics for GBS prophylaxis (n = 129, 61.1%) compared to EOGBS (n = 49, 46.2%; p = 0.012) and more doses of maternal antibiotics (3.39 doses) compared to EOGBS (1.59 doses, p = 0.010).

Differences in epidemiology and clinical manifestations of EOGBS and LOGBS support different approaches to prevent each entity. Strategies for EOGBS prevention include maternal antibiotic prophylaxis and maternal screening. The transmission and pathogenesis of LOGBS are likely different than EOGBS, creating a need for different preventative strategies. Potential mechanisms to prevent LOGBS include maternal vaccination.