Background
Group B streptococcus (GBS) is an asymptomatic colonizer of the gastrointestinal tract in up to 30% of healthy adults, and is the main risk factor for neonatal GBS infection. About 50 to 75% of newborns exposed to intravaginal GBS become colonies, and 1 to 2% of newborns of carriers mothers will develop early-onset invasive disease. In the mother, GBS may cause abortion, urinary infection, preterm birth, chorioamnionitis or puerperal endometritis. GBS screening (between the 35th and 37th gestational weeks) in pregnant women and antimicrobial prophylaxis (when indicated) may reduce neonatal morbidity and mortality.
COPAN developed a software, named Chromogenic Detection Module (CDM), that analyses plates images and links colony target color with the medium used by the laboratory. We used CDM to discriminate between positive and negative chromogenic GBS media through the automatic recognition of pigmented colonies, and WASPLab (COPAN WASP S.R.L).
