Epidemiologic characteristics of invasive group B streptococcal infections caused by rare serotypes among adults in the United States, 2007-2023

Using CDC's Active Bacterial Core surveillance data, we observed increasing incidence of rare group B Streptococcus serotypes VI and VIII, from 0.007 and 0 cases per 100,000 in 2007 to 0.14 and 0.13 in 2023, respectively. These serotypes disproportionally impacted American Indian/Alaska Native, Asian, and Native Hawaiian/Pacific Islander populations.