Group B Streptococcal Vaccine — Sisyphus Reconciled

This editorial discusses the long awaited progress in developing a maternal vaccine against group B streptococcus (GBS), a leading cause of neonatal sepsis, stillbirths, and maternal infections. Despite the success of intrapartum antibiotic prophylaxis in reducing early onset GBS disease since the 1990s, it fails to address late-onset infant disease, stillbirths, and maternal morbidity. The article highlights a pivotal study by Madhi et al. in this issue, which identifies a universal anti capsular polysaccharide (CPS) IgG antibody threshold (0.184 μg/mL) associated with a 75% reduction in infant GBS disease risk. A phase 2 trial of a hexavalent GBS conjugate vaccine (GBS6) demonstrated robust maternal immunogenicity and safe placental antibody transfer. While limitations (e.g., small sample size, South African cohort) remain, these findings pave the way for accelerated vaccine licensure using serologic correlates of protection, marking a potential turning point in global perinatal GBS prevention.

This editorial discusses the long awaited progress in developing a maternal vaccine against group B streptococcus (GBS), a leading cause of neonatal sepsis, stillbirths, and maternal infections. Despite the success of intrapartum antibiotic prophylaxis in reducing early onset GBS disease since the 1990s, it fails to address late-onset infant disease, stillbirths, and maternal morbidity. The article highlights a pivotal study by Madhi et al. in this issue, which identifies a universal anti capsular polysaccharide (CPS) IgG antibody threshold (0.184 μg/mL) associated with a 75% reduction in infant GBS disease risk. A phase 2 trial of a hexavalent GBS conjugate vaccine (GBS6) demonstrated robust maternal immunogenicity and safe placental antibody transfer. While limitations (e.g., small sample size, South African cohort) remain, these findings pave the way for accelerated vaccine licensure using serologic correlates of protection, marking a potential turning point in global perinatal GBS prevention.