To estimate vaccine coverage and characterize genomic features of pediatric invasive GBS in Japan.
Key Findings:
Estimated vaccine coverage was 98.3% for the hexavalent polysaccharide vaccine and 94.9% for the GBS-NN/NN2 protein vaccine.
Erythromycin and clindamycin resistance were observed in 61.2% and 43.5% of isolates, respectively.
Among 75 CC17 isolates (clonal complex 17), 78.7% contained only PI-2B and harbored both ermB and tetO, indicating a multidrug-resistant clone.
Evidence of nosocomial transmission and persistent regional circulation was found, particularly within ST17 and ST23 lineages.
Interpretation:
Current maternal GBS vaccine candidates could provide broad coverage for pediatric invasive infections in Japan, highlighting the urgent need to investigate transmission routes.
Limitations:
The study is retrospective and may have biases related to data collection.
The age of onset was not available, potentially affecting disease classification and the interpretation of results.
Conclusion:
The findings underscore the importance of maternal immunization strategies and further investigation into GBS transmission routes to inform effective prevention strategies.
