Strategies to Prevent Early and Late-Onset Group B Streptococcal Infection via Interventions in Pregnancy

Mahin Delara; Nirma Khatri Vadlamudi; Manish Sadarangani

doi:10.3390/pathogens12020229

Strategies to Prevent Early and Late-Onset Group B Streptococcal Infection via Interventions in Pregnancy

Pathogens. 2023 Feb 1;12(2):229. doi: 10.3390/pathogens12020229.

Authors

Mahin Delara^{1

2}, Nirma Khatri Vadlamudi^{1

2}, Manish Sadarangani^{1

2}

Affiliations

¹ Vaccine Evaluation Center, BC Children's Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada.
² Department of Pediatrics, University of British Columbia, Vancouver, BC V6H 0B3, Canada.

Abstract

Group B Streptococcus is a Gram-positive bacterium that typically colonizes 10-30% of pregnant women, causing chorioamnionitis, preterm birth, and stillbirth, as well as neonatal sepsis and meningitis with early-onset disease (EOD) or late-onset disease (LOD) due to ascending infection or transmission during delivery. While there are some differences between EOD and LOD in terms of route of transmission, risk factors, and serotypes, the only preventive approach currently is maternal intrapartum antibiotic prophylaxis (IAP) which will not be able to fully address the burden of the disease since this has no impact on LOD. Probiotics and immunization in pregnancy may be more effective than IAP for both EOD and LOD. There is mixed evidence of probiotic effects on the prevention of GBS colonization, and the data from completed and ongoing clinical trials investigating different GBS vaccines are promising. Current vaccine candidates target bacterial proteins or the polysaccharide capsule and include trivalent, tetravalent, and hexavalent protein-polysaccharide conjugate vaccines. Some challenges in developing novel GBS vaccines include the lack of a correlate of protection, the potential for serotype switching, a need to understand interactions with other vaccines, and optimal timing of administration in pregnancy to maximize protection for both term and preterm infants.

Keywords: early-onset GBS disease; group B Streptococcus; infection; late-onset GBS disease; pregnancy; prenatal immunization.

Publication types

Review

Grants and funding

M.D. received postdoctoral fellowship funding from Michael Smith Health Research BC. N.K.V. is supported by a postdoctoral fellowship from the Canadian Immunization Research Network (CIRN). M.S. is supported via salary awards from the BC Children’s Hospital Foundation and the Michael Smith Health Research BC.