Group B Streptococcus (GBS) disease is the leading cause of neonatal bacterial meningitis despite women receiving an intravenous antibiotic prophylaxis during labor. We aimed to describe GBS meningitis in children <1 year old in France.

Clinical and biological data of GBS meningitis gathered by the Association Clinique et Thérapeutique Infantile du Val de Marne (ACTIV) were analyzed. The cases were classified by age: 0–6 days old (early-onset disease [EOD]), newborns and infants 7–89 days old (late-onset disease [LOD]: LOD1, 7–26 days; LOD2, 27–89 days), and infants aged 3 months to 1 year (infant disease).

Among 848 GBS meningitis cases from 2001 to 2014, the incidence of EOD decreased by 63.3% (95% confidence interval [CI], 43.9%–80.1%]; P < .001) and that of LOD increased by 58.1% (95% CI, 39.1%–75.5%); P < .001) (52.9% and 64.3% for LOD1 and LOD2, respectively). The mean gestational age (GA) decreased significantly for EOD, LOD1, LOD2, and infant disease cases (38.7, 38.6, 37.3, and 34 weeks, respectively). Serotype III accounted for 83.9% of cases, with no significant difference among the 4 groups or by GA. The frequency of GBS belonging to the clonal complex 17 did not differ among the 4 groups. Case mortality was 11.4%.

In the era of intravenous antibiotic prophylaxis, we found decreased incidence of early-onset GBS meningitis but, unexpectedly, increased incidence of LOD. These data underline the interest in the development of effective GBS vaccines for pregnant women.