From Dysbiosis to Disease: How Vaginal Microbiota Shape Group B Streptococcus Pathogenesis

Host–microbe interactions refer to the dynamic relationships between hosts, such as humans, and the microorganisms present on or inside them. These associations can be beneficial, like gut bacteria facilitating digestion, or harmful, such as pathogens leading to disease. This review focuses on the reproductive tract, specifically the vaginal microbiome. Typically, a healthy vaginal microbiome is dominated by Lactobacillus species, which help protect against infections by pathogens. Dysbiosis, or a microbial imbalance, allows pathogens to invade. One such pathogen is Streptococcus agalactiae (group B Streptococcus , GBS), which can colonize the vaginal microbiome and cause infections. GBS infection during pregnancy is particularly concerning and is a major cause of adverse pregnancy outcomes. This review will explore host–microbe interactions in the vaginal microbiome, with an emphasis on GBS infection, its virulence, and current treatment strategies.