Point of care testing of GBS, isn’t it obvious?

Review of group B streptococcal diseases in newborns, of prevention strategies. Review of advantages and weakness of antenatal screening. A rapid test is needed for intrapartum screening: why, expected advantages and weakness, Wishlist of expected characteristics, available tests in 2018

Evolution of antimicrobial susceptibility patterns of clinical group B streptococci isolated in Belgium

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Chapter 42 Group B streptococci

editorial reviewedLe streptocoque du groupe B (GBS) reste une cause majeure d’infections materno-fœtales et néonatales graves. En Belgique, l’incidence estimée de l’infection invasive du nouveau-né, à début précoce, s’élève à 0,3 à 0,8 pour mille naissances vivantes. En termes de santé publique, les répercussions de ces infections sont très importantes en raison de la mortalité et des séquelles neurologiques qu’elles peuvent laisser chez le nouveau-né, mais aussi des complications maternelles du post-partum. L’immunoprophylaxie serait théoriquement la stratégie de prévention la plus intéressante, mais les vaccins ne sont pas encore disponibles. En attendant, la stratégie recommandée est fondée sur une approche de dépistage prénatal universel avec, si nécessaire l’intégration d’options basées sur le risque. L’administration d’antibiotiques au cours de l’accouchement, orientée par un dépistage de colonisation maternelle par GBS chez toutes les patientes à 35-37 semaines de gestation, est considérée actuellement comme la meilleure stratégie visant à réduire l’incidence de ces infections. Dans un futur proche, le dépistage intrapartum pourrait remplacer le dépistage prénatal. L’objectif général des recommandations présentées ci-dessus est de réduire de 70 à 80 % le nombre d’infections précoces à GBS qui surviendraient en l’absence de toute interventio

Contrôle de qualité externe - Souche de Streptococcus agalactiae

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GBS colonization and screening in pregnancy: how does it work in Europe?

In Europe, as in North America, GBS infections among infants are associated to high morbidity and mortality even if some differences exist between different European countries. During the past two decades, major initiatives have been proposed to prevent early onset GBS disease (EOD) and they are still subject of controversy. Several European countries have issued guidelines for the prevention of neonatal GBS diseases, either universal screening-based or risk-based strategy, others have no official guidelines at all. In countries having guidelines, despite considerable efforts and economic resources spent on intrapartum antimicrobial prophylaxis for GBS EOD, cases continue to occur. Among these cases there are a lot of missed opportunities to administer IAP but there are also false negative screening. Therefore in the setting of a maternal GBS-screening program and successful implementation of the strategy, efforts to improve screening for GBS status remain important. The natural reservoir for GBS is the gastrointestinal tract and is likely the source for vaginal colonization. Among pregnant women, GBS carriage rate in the vaginal and rectal flora ranges from 10% up to 30%. Critical factors that influence the accuracy of detecting GBS maternal colonization are the choice of the body sites sampled, the timing of sampling and the use of selective culture media. The evolution of the different culture options to improve the GBS-screening strategy will be reviewed. If the optimal time for performing antenatal cultures is between 35 to 37 weeks’ gestation, as GBS carriage is highly variable, the predictive values of GBS antenatal cultures are not always as good predictors of the maternal GBS status at presentation for delivery as expected. Potential alternative to antenatal GBS-screening culture is the identification of GBS colonization at presentation for delivery. Use of a reliable, sensitive, easy to use rapid test should be cost effective leading to the prevention of more EOGBS cases while reducing the number of unnecessarily IAP. Advances of polymerase chain reaction (PCR) and fluorescence labeling technologies has provided new detection tools for bacterial identification. Therefore, commercialization of rapid detection of GBS through real-time PCR offers the potential for GBS detection among women without prenatal care or those in whom no antenatal culture was collected. However questions of costs and logistics remain unanswered. Could such rapid intrapartum test replace existing screening strategies or could it be used in conjunction with them? Colonizing rates and recommended screening procedures existing through Europe will be reviewed.DEVANI (DEsign of a Vaccine Against Neonatal Infections) Project full title: Design of a vaccine to immunize neonates against GBS infections through a durable maternal immune response

GBS AND THE NEONATE: PREVENTION STRATEGIES

peer reviewedStreptococcus agalactiae, or group B streptococcus (GBS), remains the leading cause of neonatal sepsis and meningitis, early onset and late onset diseases (EOD, LOD). Where consensus guidelines to detect and treat intrapartum women with GBS colonization have been widely adopted, incidence of neonatal EOD has dramatically declined. In response to both successful impacts on the incidence of GBS-EOD and analyses of missed opportunities, the first American guidelines for prevention issued in the 90s have since been adapted in several stages to improve their efficacy. In some countries in Europe, nationwide guidelines, whether screening-based or risk-based, for the prevention of neonatal GBS diseases have also been issued and adopted, with the expected impact on incidence of GBS-EOD. In spite of universal screening, in spite of the great progress that has been made, GBS-EOD continues to occur and the GBS burden remains a significant public health issue. Continuous efforts to improve screening for GBS status continue to be important and may be able to take advantage of new rapid diagnostic technologies. The current screening-based strategy for prevention is highly effective but imperfect. Given the challenges, limitations and potential complications of maternal intrapartum prophylaxis, a new approach is still needed. Maternal immunization against GBS is an attractive alternative for the prevention of not only neonatal diseases but also stillbirths and maternal diseases. Vaccines against GBS may likely become the most effective and sustainable long-term preventive strategy