Maternal immunization against group B Streptococcus: Immune correlates, microbiome trade-offs, and global...

Area of Science:

• Immunology
• Microbiology
• Global Health

Background:

• Group B Streptococcus (GBS) is a major cause of neonatal sepsis, meningitis, and stillbirth globally.
• Intrapartum antibiotic prophylaxis (IAP) reduces early-onset GBS but doesn't prevent late-onset disease, maternal colonization, or stillbirths, and faces implementation hurdles in low- and middle-income countries (LMICs).

Purpose of the Study:

• To critically examine maternal GBS vaccine development progress.
• To integrate immunological, biological, and implementation factors for future vaccine impact.
• To inform vaccine evaluation, regulation, and policy for global deployment.

Main Methods:

• Review of current progress in maternal GBS vaccine development.
• Integration of immune correlates of protection, microbiome-related trade-offs of IAP, and global implementation challenges.
• Analysis of operational and policy considerations for vaccine introduction in LMICs.

Main Results:

• Advances and uncertainties exist in defining immune correlates for regulatory approval.
• Emerging evidence suggests microbiome perturbations from peripartum antibiotics, though clinical significance is uncertain.
• Operational and policy considerations for LMIC vaccine introduction are analyzed.

Conclusions:

• Maternal vaccination is a promising complementary strategy for equitable GBS disease prevention.
• An integrated framework is needed to guide evaluation and deployment of maternal GBS vaccines.
• Addressing implementation challenges is crucial for global impact, especially in LMICs.