Distribution of group B streptococci serotypes on women nasopharynx.

Group B Streptococcus (GBS) is a significant pathogen responsible for neonatal infections, primarily transmitted through maternal carriage. However, current preventive strategies, such as intrapartum antibiotic prophylaxis, present limitations and are ineffective in preventing late-onset neonatal infections. This study aimed to assess the prevalence and serotype distribution of GBS in the nasopharynx of women of reproductive age, providing data to the potential implementation of a novel hexavalent capsular vaccine (GBS6). Nasopharyngeal swabs were collected from 500 women and analyzed using a qPCR assay targeting the cfb gene to detect GBS and the cps locus. GBS was identified in 7.4 % of patients, with serotype Ia being the most prevalent. Other serotypes detected included II, V, Ib, III, and IV. These findings suggest that the nasopharynx may act as a reservoir for GBS in women of reproductive age. The results also highlight the importance of developing preventive strategies focused on upper respiratory tract colonization. Additionally, the potential introduction of the GBS6 vaccine could provide significant coverage against circulating GBS serotypes.