Group B Streptococcus Vaccines: Progress and Potential

Group B Streptococcus (GBS, Streptococcus agalactiae) is a pathogen that causes sepsis and meningitis, particularly in newborns, as well as severe infections in the elderly and those at high risk. For many years, the administration of intrapartum antimicrobial prophylaxis (IAP) has been a standard method to prevent neonatal GBS infection. However, IAP may be unsuitable in low-income settings due to its high cost and difficult accessibility to medical institutions. Additionally, IAP may lead to the emergence of antimicrobial-resistant bacteria. Hence, an alternative method for the control of GBS, such as a vaccine, is needed. An effective vaccine will likely prevent the further spread of GBS and be cost-effective compared with IAP. GBS vaccines have been under development for the past two decades, and several candidates have shown potential. In this review, we discuss the current development of GBS vaccines, including types and their implementation in different target populations.