Researchers are studying group b streptococcus, a bacterium that can cause infection, with some focusing on its potential impact on newborns and pregnant women. The use of antibiotics during pregnancy may be linked to a higher risk of group b streptococcus in newborns, and there are concerns about antimicrobial resistance trends in the bacterium. A vaccine for group b streptococcus is also being developed and tested for safety and effectiveness in pregnant women and their infants.