Selectivity evaluation of a new chromogenic medium to detect group B Streptococcus.

Background: Group B Streptococcus (GBS) is an important pathogen that causes serious infections in newborns. Pregnant screening and intrapartum antibiotic prophylaxis are actually the strategies to prevent GBS disease in neonates because vaccination is under investigation. Materials and Methods: Simultaneously, 156 isolates of GBS and 156 isolates other than GBS covering 17 different species, were tested to evaluate the selectivity of a new chromogenic medium to screen GBS. Results: The new new chromogenic medium showed an excellent performance, exhibiting a very high level of inclusivity (100%) and exclusivity (96.1%).