Group B Streptococcus
Blue, colourless or inhibited
GBS in pregnant women: The Group B Streptococci (GBS), also known under the name of Streptococcus agalactiae, are the cause of numerous infections in adults but mostly an important cause of serious neonatal infections, occuring in the three first weeks of life. Studies indicate that approximately 12-27 % of pregnant women are colonised by GBS. (WHO, Infectious diseases, Group B Streptococcus). Detecting vaginal (and in some countries also rectal) colonisation by GBS in pregnant women is the most effective strategy to prevent infection transmission during baby delivery.
Worldwide, official guidelines recommend prenatal screening of GBS in the last month of pregnancy. In GBS-carrying women, this screening allows determining the need of intrapartum antibiotic prophylaxy, which has been proved effective in preventing the infections occuring in the first week of life (known as early-onset GBS infections).
CHROMagar™ StrepB is a selective chromogenic culture medium that is intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization in pregnant women. This medium supports the growth of hemolytic and non-hemolytic GBS strains. The test is performed by direct, or after enrichment, plating of urine, vaginal and/or vagino/rectal swabs obtained from pregnant women. CHROMagar™ StrepB results can be interpreted after 18-24 h aerobic incubation at 35-37 °C.
CHROMagar™ StrepB is not intended to diagnose infection nor to guide nor monitor treatment for infections. Further identification, susceptibility testing and epidemiological typing is needed on suspect colonies.