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Background: Group B Streptococcus (GBS) infection remains a leading cause of newborn morbidity and mortality. The study aimed to determine the adherence rate to the universal screening policy a decade after its introduction. Secondly, whether the timing of antibiotics given in GBS carriers reduces the incidence of neonatal sepsis. Methods: Delivery records at Hong Kong Baptist Hospital in 2022 were examined to retrieve antenatal and intrapartum details regarding maternal GBS carrier status, previous maternal GBS carrier status, antibiotic treatment, timing of treatment, neonatal condition at birth and whether the neonate had sepsis. Univariate statistics was used to assess the relationship between maternal GBS carrier and neonatal sepsis overall. Incidence of neonatal sepsis was stratified according to mode of delivery and timing of antibiotic. Results: The adherence rate to the universal GBS screening policy was 97%. The risk of neonatal sepsis was 5.45 (95% CI 3.05 to 9.75) times higher in women who were GBS screened positive when compared to non-GBS carriers (p < 0.001). Amongst term neonates from GBS carriers delivered by Caesarean section, the risk of neonatal sepsis significantly decreased by 70% after antenatal antibiotic treatment (p = 0.041) whereas in term neonates delivered vaginally, the risk of neonatal sepsis decreased by 71% (p = 0.022) if intrapartum antibiotic prophylaxis was given 4 or more hours. Conclusion: Giving antenatal antibiotic treatment before Caesarean section or intrapartum antibiotic prophylaxis for 4 or more hours before vaginal delivery may decrease the risk of neonatal sepsis in term neonates delivered from GBS carriers. [ABSTRACT FROM AUTHOR]

Group B Streptococcus (GBS) is a frequent colonizer of the human genital and gastrointestinal tract. In pregnant or postpartum persons, colonization is often asymptomatic and can contribute to infectious morbidity in both the parturient and the newborn. The prevalence of invasive GBS disease has dramatically decreased over the past 3 decades. However, despite standardized clinical algorithms, GBS disease remains a public health concern. Our review summarizes the GBS bacteria pathophysiology, morbidity, management guidelines, and summarizes ongoing research. While novel testing and parturient vaccination are being explored, barriers exist, preventing guideline updates and widespread implementation. [ABSTRACT FROM AUTHOR]

Background: Group B Streptococcus (GBS) is the leading cause of neonatal meningitis responsible for a substantial cause of death and disability worldwide. The vast majority of GBS neonatal meningitis cases are due to the CC17 hypervirulent clone. However, the cellular and molecular pathways involved in brain invasion by GBS CC17 isolates remain largely elusive. Here, we studied the specific interaction of the CC17 clone with the choroid plexus, the main component of the blood-cerebrospinal fluid (CSF) barrier. Methods: The interaction of GBS CC17 or non-CC17 strains with choroid plexus cells was studied using an in vivo mouse model of meningitis and in vitro models of primary and transformed rodent choroid plexus epithelial cells (CPEC and Z310). In vivo interaction of GBS with the choroid plexus was assessed by microscopy. Bacterial invasion and cell barrier penetration were examined in vitro, as well as chemokines and cytokines in response to infection. Results: GBS CC17 was found associated with the choroid plexus of the lateral, 3rd and 4th ventricles. Infection of choroid plexus epithelial cells revealed an efficient internalization of the bacteria into the cells with GBS CC17 displaying a greater ability to invade these cells than a non-CC17 strain. Internalization of the GBS CC17 strain involved the CC17-specific HvgA adhesin and occurred via a clathrin-dependent mechanism leading to transcellular transcytosis across the choroid plexus epithelial monolayer. CPEC infection resulted in the secretion of several chemokines, including CCL2, CCL3, CCL20, CX3CL1, and the matrix metalloproteinase MMP3, as well as immune cell infiltration. Conclusion: Our findings reveal a GBS strain-specific ability to infect the blood-CSF barrier, which appears to be an important site of bacterial entry and an active site of immune cell trafficking in response to infection. [ABSTRACT FROM AUTHOR]

Group B streptococcus (GBS) poses a significant threat to neonates, leading to morbidity and mortality. Intrapartum antibiotics, although effective, have limitations, prompting the exploration of maternal vaccination. This study reviews the current evidence for maternal GBS vaccination in the prevention of early‐onset GBS disease in newborns. A search on Google Scholar, PubMed, and Scopus identified studies assessing the impact of maternal GBS vaccination on early‐onset GBS disease. Inclusion criteria comprised English‐language clinical trials or observational studies. Data extraction included study details, immunogenicity profiles, effectiveness, safety outcomes, and relevant findings. Qualitative synthesis was employed for data analysis. Five studies meeting the inclusion criteria were reviewed. Maternal GBS vaccines demonstrated efficacy with sustained immunogenicity. Adverse events, although documented, were predominantly non‐severe. Variability in immune responses and maternal‐to‐infant antibody ratios show the need for tailored vaccination approaches. Long‐term follow up and surveillance are essential to assess persistence and identify unintended effects. Positive outcomes in vaccine efficacy support GBS vaccination integration into maternal health programs. Implementation challenges in diverse healthcare infrastructures require tailored approaches, especially in resource‐limited settings. Overcoming cultural barriers and ensuring healthcare provider awareness are crucial for successful vaccination. Synopsis: Maternal GBS vaccination effectively prevents early‐onset group B streptococcus (GBS) disease in newborns, showing sustained immunogenicity. Although adverse events occurred, they were mostly non‐severe. [ABSTRACT FROM AUTHOR]

Prophages, viral genomes integrated into bacterial genomes, are known to enhance bacterial colonization, adaptation, and ecological fitness, providing a better chance for pathogenic bacteria to disseminate and cause infection. Streptococcus agalactiae (Group B Streptococcus or GBS) is a common bacterium found colonizing the genitourinary tract of humans. However, GBS-colonized pregnant women are at risk of passing the organism to the neonate, where it can cause severe infections. GBS typically encode one or more prophages in their genomes, yet their role in pathogen fitness and virulence has not yet been described. Sequencing and bioinformatic analysis of the genomic content of GBS human isolates identified 42 complete prophages present in their genomes. Comparative genomic analyses of the prophage sequences revealed that the prophages could be classified into five distinct clusters based on their genomic content, indicating significant diversity in their genetic makeup. Prophage diversity was also identified across GBS capsule serotypes, sequence types (STs), and clonal clusters (CCs). Comprehensive genomic annotation revealed that all GBS strains encode paratox, a protein that prevents the uptake of DNA in Streptococcus, either on the chromosome, on the prophage, or both, and each prophage genome has at least one toxin-antitoxin system. [ABSTRACT FROM AUTHOR]

Background: Group B Streptococcus (GBS) causes invasive infections in newborns and elderly individuals, but is a noninvasive commensal bacterium in most immunocompetent people. Recently, the incidence of invasive GBS infections has increased worldwide, and there is growing interest in the molecular genetic characteristics of invasive GBS strains. Vaccines against GBS are expected in the near future. Here, we aimed to analyze the molecular epidemiology of GBS according to the invasiveness in South Korea. Methods: We analyzed GBS isolates collected and stored in two hospitals in South Korea between January 2015 and December 2020. The invasiveness of these isolates was determined via a retrospective review of clinical episodes. Totally, 120 GBS isolates from 55 children and 65 adults were analyzed. Serotype and sequence type (ST) were determined using multiplex polymerase chain reaction (PCR) and multilocus sequence typing, respectively. Fourteen virulence factor-encoding genes of GBS were analyzed using multiplex PCR. Results: Forty one (34.2%) were invasive infection-related GBS isolates (iGBS). The most frequently detected serotype was III (39/120, 32.5%), and it accounted for a high proportion of iGBS (21/41, 51.2%). The most frequent ST was ST19 (18/120, 15.0%), followed by ST2 (17/120, 14.2%). Serotype III/ST17 was predominant in iGBS (12/41, 29.3%), and all 17 ST2 strains were noninvasive. The distribution of most of the investigated virulence factors was not significantly related to invasiveness; noteworthily, most of the serotype III/ST17 iGBS carried pilus island (PI) 2b (10/12, 83.3%), and the prevalence of fbsB was significantly low compared with noninvasive GBS isolates (P = 0.004). Characteristically, the combination of bca(+)-cspA(+)-pavA(+)-fbsB(-)-rib(+)-bac(-) was predominant in iGBS (24.4%, 10/41). Conclusions: Serotype III/ST17 GBS carrying PI-2b was frequently detected in iGBS. There was no significant association between invasiveness and the pattern of virulence factors; however, a specific combination of virulence factors was predominant in iGBS. [ABSTRACT FROM AUTHOR]

Background: Maternal rectovaginal colonization by group B Streptococcus (GBS) increases the risk of perinatal GBS disease that can lead to death or long-term neurological impairment. Factors that increase the risk of rectovaginal GBS carriage are incompletely understood resulting in missed opportunities for detecting GBS in risk-based clinical approaches. There is a lacking consensus on whether gestational diabetes mellitus (GDM) is a risk factor for rectovaginal GBS. This systematic review and meta-analysis aims to address current conflicting findings and determine whether GDM should be clinically considered as a risk factor for maternal GBS colonization. Methods: Peer-reviewed studies that provided GDM prevalence and documented GBS vaginal and/or rectal colonization in women with and without GDM were included in this analysis. From study inception to October 30, 2023, we identified 6,275 relevant studies from EMBASE and PUBMED of which 19 were eligible for inclusion. Eligible studies were analyzed and thoroughly assessed for risk of bias with a modified Newcastle-Ottawa Scale that interrogated representativeness and comparability of cohorts, quality of reporting for GDM and GBS status, and potential bias from other metabolic diseases. Results were synthesized using STATA 18 and analyzed using random-effects meta-analyses. Results: Studies encompassed 266,706 women from 10 different countries, with study periods spanning from 1981 to 2020. Meta-analysis revealed that gestational diabetes is associated with a 16% increased risk of rectovaginal GBS carriage (OR 1.16, CI 1.07–1.26, P = 0.003). We also performed subgroup analyses to assess independent effects of pregestational vs. gestational diabetes on risk of maternal GBS carriage. Pregestational diabetes (Type 1 or Type 2 diabetes mellitus) was also associated with an increased risk of 76% (pooled OR 1.76, CI 1.27–2.45, P = 0.0008). Conclusions: This study achieved a consensus among previously discrepant observations and demonstrated that gestational diabetes and pregestational diabetes are significant risk factors for maternal rectovaginal carriage of GBS. Recognition of GDM as a risk factor during clinical decisions about GBS screening and intrapartum antibiotic prophylaxis may decrease the global burden of GBS on maternal-perinatal health. [ABSTRACT FROM AUTHOR]

Objectives: Certain Group B Streptococcus (GBS) genotypes are associated with invasive disease in neonates. We conducted a comparative genomic analysis of GBS isolates from neonatal disease and maternal carriage in the Netherlands to determine distribution of genetic markers between the two host groups. Methods: Whole genome sequencing was used to characterise 685 neonatal invasive isolates (2006-2021) and 733 maternal carriage isolates (2017-2021) collected in the Netherlands. Results: Clonal complex (CC) 17 and serotype III were significantly more common in disease while carriage isolates were associated with serotypes II, IV, V as well as CC1. Previously reported CC17-A1 sub-lineage was dominant among disease isolates and significantly less common in carriage. The phiStag1 phage, previously associated with expansion of invasive CC17 isolates in the Netherlands, was more common among disease isolates compared to carriage isolates overall, however it was equally distributed between CC17 isolates from carriage and disease. Prevalence of antimicrobial resistance genes was overall lower in disease compared to carriage isolates, but increased significantly over time, mediated by rise in prevalence of a multidrug resistance element ICESag37 among disease isolates. Conclusion: There is a stable association between certain GBS genotypes and invasive disease, which suggests opportunities for developing more precise disease prevention strategies based on GBS targeted screening. In contrast, GBS mobile genetic elements appear less likely to be correlated with carriage or disease, and instead are associated with clonal expansion events across the GBS population. [ABSTRACT FROM AUTHOR]

Objective To analyze the risk factors for preterm birth in pregnant women with group B streptococcus (GBS) infection in a hospital and investigate the pbp2.x gene mutation of GBS in pregnant women with preterm birth. Methods A total of 199 pregnant women with GBS infection who delivered in the hospital from January 2022 to May 2023 were selected and divided into the observation group and the control group according to whether they were preterm or not. Binary logistic regression model and receiver operating characteristic curve (ROC) were used to analyze the risk factors of preterm birth in pregnant women with GBS infection, First generation sequencing of pbp2x gene was performed on GBS samples from pregnant women with preterm birth. Results Among the 199 cases pregnant women with GBS infection, 41(20.6%) had pre- term birth. Logistic regression analysis showed that age [odds ratio(OR)=1.151.P=0.004] and the number of abnormal items in oral glucose tolerance test (OGTT) (OR=2,995, P<0.001) were independent risk factors for preterm birth in pregnant women with GBS infection. The area under the curve(AUC) of the combination of the two risk factors for preterm birth was 0. 783. the best sensitivity was 75.6%.and the specificity was 69.0%, which was higher than that of single risk factor. Three missense mutations (1129G>A,1148T> G.1528AG) in pbp2x gene were found by Sanger sequencing. No mutation was found that could reduce the susceptibility of GBS to penicillin, Conclusion Age and the number of abnormal items in OGTT are risk factors for preterm birth in pregnant women with GBS infection, and the combination of the two factors is better than each one alone in predicting preterm birth. No mutation of php2r gene affecting penicillin sensitivity has been found in GBS from pregnant women with preterm birth. [ABSTRACT FROM AUTHOR]

Background: Maternal Group B Streptococcus (GBS) colonization is influenced by many factors but results are inconsistent. Consideration of antenatal risk factors may help inform decision making on GBS microbiological culture screening where universal screening is not standard of care. We sought to identify independent predictors of GBS colonization at 34–37 weeks gestation incorporating vaginal symptoms, perineal hygiene measures, sexual activity, and a potential novel factor, constipation. Methods: In this prospective cross-sectional study, 573 women at 34–37 weeks gestation had an ano-vaginal swab taken and sent for selective culture for GBS. Women were asked about vaginal bleeding, discharge, irritation and candidiasis, antibiotic use during pregnancy, ano-vaginal hygiene practices such as douching and perineal cleansing after toileting, sexual intercourse related activities, and a potential novel factor for GBS carriage, constipation. Maternal basic demographics and obstetric-related characteristics were also collected. Bivariate analyses were performed to identify associates of GBS colonization. All variables with p < 0.05 found on bivariate analysis were then included into a model for multivariable binary logistic regression analysis to identify independent risk factors for GBS colonization. Results: GBS colonization was found in 235/573 (41.0%) of participants. Twenty six independent variables were considered for bivariate analysis. Eight were found to have p < 0.05. Following adjusted analysis, six independent predictors of GBS colonization were identified: ethnicity, previous neonatal GBS prophylaxis, antenatal vaginal irritation, antibiotic use, recent panty liner use, and frequency of sexual intercourse. Vaginal discharge and perineal cleansing were not associated after adjustment. Recent douching and constipation were not associated on bivariate analysis. Conclusion: The identification of independent predictors of GBS colonization in late pregnancy may inform the woman and care provider in their shared decision making for microbiological screening at 35–38 weeks gestation in locations where universal GBS screening is not standard of care. Ethics oversight: This study was approved by the Medical Ethics Committee of University Malaya Medical Centre (UMMC) on August 9, 2022, reference number 2022328-11120. [ABSTRACT FROM AUTHOR]

Streptococcus agalactiae is a highly invasive bacterium that causes significant economic losses in tilapia aquaculture around the world. Furthermore, it is a pathogen for mammals, including humans, emphasizing its importance in One Health. The aim of this work was to evaluate the evolution of clinical and histopathological lesions caused by acute infection with two serotypes of S. agalactiae. For this, two strains isolated from natural outbreaks in Brazilian aquaculture farms (S13, serotype Ib; S73, serotype III) were used to challenge juvenile Nile tilapia (Oreochromis niloticus) intraperitoneally. Target organ samples were collected ten times, between 1 and 96 h post-infection, for microbiological and histopathological analyses. Anorexia was the first clinical sign and the first death occurred at 24 and 30 h in the fish infected with strains S13 and S73, respectively. Serotype Ib initially caused more pronounced lesions in the nervous system; however, serotype III lesions progressed more aggressively, reaching the same severity as those of serotype Ib. This trend was repeated in the mortality curve after 32 h. These results elucidated the important stages in the pathogenesis of S. agalactiae serotypes Ib and III in tilapia and suggest "tips and tricks" to improve the positive culture rate in the clinical diagnosis of infections in some tissues. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV) is a well-established causal agent of cervical cancer, and the first group of viruses to have been acknowledged to prompt carcinogenesis. They are linked with cancers of the uterine cervix, anogenital tumours, and head and neck malignancies. Cervical cancer is by far the most common HPVrelated disease, with about 99% of cervical cancer cases caused by persistent genital high-risk (HR) HPVs, especially types 16 and 18. Methodology: A hospital-based descriptive analytical study of 300 consenting HIV-infected women on antiretroviral therapy (ART), selected from the three senatorial districts of Plateau State, Nigeria, was conducted over a period of 24 months (November 2018 to November 2020). Blood and cervical specimens were collected from each participant. HIV status was confirmed by standard rapid test on serum sample, CD4+ cell count was determined by flow cytometry and HIV viral load estimation was done by GeneXpert nucleic acid amplification technique. Cervical cytology was performed by Papanicolaou (Pap smear) on the cervical specimen and reported according to the 2004 Bethesda system classification. HPV antigen was first detected on the cervical specimen using ELISA, and samples positive for HPV antigen were then subjected to multiplex PCR amplification of E6 and E7 genes to detect HR-HPV (16 and 18) and other HPV types. Standard questionnaires were administered to obtain information on biodata, risk factors and clinical presentations. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 26.0, and significance level was determined at p<0.05. Results: Of the 300 participants, 84 were positive for HPV of any type, giving an overall prevalence of HPV infection of 28.0%. The prevalence of HPV-16 and HPV-18 types were 5.0% (15/300) and 5.3% (16/300) respectively. Cytological analysis showed that 36.3% (109/300) of the participants had cervical abnormalities ranging from low-grade to high grade squamous intraepithelial lesions and cervical intraepithelial neoplasia. HPV prevalence of 46.8% (51/109) in women with cervical abnormalities was significantly higher than 17.3% (33/191) in women with normal cervical cytology (OR 4.2, p<0.0001). HPV prevalence was higher in women with AG-US (100.0%), ASC-US (78.8%), AC-US (66.7%), ASC-H (33.3%), HSIL (33.3%), HSIL (23.8%), and LSIL (41.2%) compared with women with normal cervical cytology (p<0.001). Aside educational level (p=0.03), none of the analyzed sociodemographic characteristics or risk factors for cervical cancer was significantly associated with HPV infection in the study (p>0.05). Conclusion: This study showed high prevalence of HPV infections among HIV-infected patients on ART in Plateau State, north-central Nigeria including detection of high-risk HPV types 16 and 18, which are major risk factors for progression of cervical intraepithelial neoplasia to cervical cancer. [ABSTRACT FROM AUTHOR]

Aim: To compare the prophylactic efficacy of ampicillin and clindamycin against vertical transmission of group B Streptococcus from mothers to their infants by evaluating the rates of group B Streptococcus colonisation. Methods: We retrospectively extracted data for mothers who delivered at Showa University Northern Yokohama Hospital between 1 October 2017 and 31 March 2021 and tested positive for antepartum group B Streptococcus, and their infants. The chi‐square test was used to compare the rates of group B Streptococcus colonisation, sepsis, and meningitis. We conducted a multivariate logistic regression analysis, including the time interval between membrane rupture and delivery, chorioamnionitis, and maternal intrapartum fever (≥38.0°C). Results: Two hundred fifty‐nine mothers and their infants were eligible. Ampicillin and clindamycin were administered to 150 and 109 mothers, respectively. In the ampicillin and clindamycin groups, 12.0% (18/150) and 37.6% (41/109) infants were group B Streptococcus positive, respectively. The rate of group B Streptococcus colonisation among infants was significantly lower in the ampicillin group (p < 0.001). Multivariate regression analysis showed similar results (p < 0.001). No sepsis or meningitis cases were observed in either group. Conclusion: Prophylactic efficacy of clindamycin against the vertical transmission of group B Streptococcus is lower than that of ampicillin. [ABSTRACT FROM AUTHOR]

Objectives: Group B streptococcus (GBS) colonization among pregnant women is the leading cause of neonatal infection. Intrapartum antibiotic prophylaxis (IAP) is the most effective method to reduce the incidents of neonatal sepsis. We describe compliance with GBS management and the implementation of IAP in the context of the long-term effect of antibiotics. Material and methods: The study was conducted among 249 childbearing women hospitalized between January 2022 and February 2022 at University Clinical Center in Gdansk, Poland. The data were obtained from the questionnaire and medical records. We analyzed maternal colonization with GBS, compliance with GBS screening and treatment guidelines, risk factors contributing to GBS colonization, IAP administration, and neonatal congenital infection occurrence. Results: Of all patients, 240 (96.4%) were screened for GBS, 215 (89.6%) between 35-37 weeks of gestation. Fifty (20%) were GBS-positive, 184 (74%) negative, 15 (6%) had unknown GBS status. There were no significant differences between the GBS-positive and GBS-negative groups in maternal age, mode of delivery, gestational age at birth, maternal comorbidities, parity, GBS status in previous pregnancies, and the development of infection among infants of both groups, regardless of IAP administration. Of all the studied women, 158 (63.5%) received antibiotics, 91 (36.5%) did not. The study showed the low positive and the high negative predictive value of the antenatal GBS screening test. Conclusions: We found that compliance with the universal GBS screening is widespread. The management of women with absent or only partial screening test requires assessing the risk factors before administering IAP. [ABSTRACT FROM AUTHOR]

Abstract Background Group B Streptococcus (GBS) infection remains a leading cause of newborn morbidity and mortality. The study aimed to determine the adherence rate to the universal screening policy a decade after its introduction. Secondly, whether the timing of antibiotics given in GBS carriers reduces the incidence of neonatal sepsis. Methods Delivery records at Hong Kong Baptist Hospital in 2022 were examined to retrieve antenatal and intrapartum details regarding maternal GBS carrier status, previous maternal GBS carrier status, antibiotic treatment, timing of treatment, neonatal condition at birth and whether the neonate had sepsis. Univariate statistics was used to assess the relationship between maternal GBS carrier and neonatal sepsis overall. Incidence of neonatal sepsis was stratified according to mode of delivery and timing of antibiotic. Results The adherence rate to the universal GBS screening policy was 97%. The risk of neonatal sepsis was 5.45 (95% CI 3.05 to 9.75) times higher in women who were GBS screened positive when compared to non-GBS carriers (p

Abstract Background Group B Streptococcus (GBS) is the leading cause of neonatal meningitis responsible for a substantial cause of death and disability worldwide. The vast majority of GBS neonatal meningitis cases are due to the CC17 hypervirulent clone. However, the cellular and molecular pathways involved in brain invasion by GBS CC17 isolates remain largely elusive. Here, we studied the specific interaction of the CC17 clone with the choroid plexus, the main component of the blood-cerebrospinal fluid (CSF) barrier. Methods The interaction of GBS CC17 or non-CC17 strains with choroid plexus cells was studied using an in vivo mouse model of meningitis and in vitro models of primary and transformed rodent choroid plexus epithelial cells (CPEC and Z310). In vivo interaction of GBS with the choroid plexus was assessed by microscopy. Bacterial invasion and cell barrier penetration were examined in vitro, as well as chemokines and cytokines in response to infection. Results GBS CC17 was found associated with the choroid plexus of the lateral, 3rd and 4th ventricles. Infection of choroid plexus epithelial cells revealed an efficient internalization of the bacteria into the cells with GBS CC17 displaying a greater ability to invade these cells than a non-CC17 strain. Internalization of the GBS CC17 strain involved the CC17-specific HvgA adhesin and occurred via a clathrin-dependent mechanism leading to transcellular transcytosis across the choroid plexus epithelial monolayer. CPEC infection resulted in the secretion of several chemokines, including CCL2, CCL3, CCL20, CX3CL1, and the matrix metalloproteinase MMP3, as well as immune cell infiltration. Conclusion Our findings reveal a GBS strain-specific ability to infect the blood-CSF barrier, which appears to be an important site of bacterial entry and an active site of immune cell trafficking in response to infection.

Group B Streptococcus sequence type 103 is known primarily as a bovine mastitis pathogen. In Brazil, it has circulated in cattle and humans since the 1990s. It lacks scpB and, in humans, was found only among carriage isolates. Bovine–human interspecies transmission may have contributed to its evolution and spread.

Abstract Background Group B Streptococcus (GBS) causes invasive infections in newborns and elderly individuals, but is a noninvasive commensal bacterium in most immunocompetent people. Recently, the incidence of invasive GBS infections has increased worldwide, and there is growing interest in the molecular genetic characteristics of invasive GBS strains. Vaccines against GBS are expected in the near future. Here, we aimed to analyze the molecular epidemiology of GBS according to the invasiveness in South Korea. Methods We analyzed GBS isolates collected and stored in two hospitals in South Korea between January 2015 and December 2020. The invasiveness of these isolates was determined via a retrospective review of clinical episodes. Totally, 120 GBS isolates from 55 children and 65 adults were analyzed. Serotype and sequence type (ST) were determined using multiplex polymerase chain reaction (PCR) and multilocus sequence typing, respectively. Fourteen virulence factor-encoding genes of GBS were analyzed using multiplex PCR. Results Forty one (34.2%) were invasive infection-related GBS isolates (iGBS). The most frequently detected serotype was III (39/120, 32.5%), and it accounted for a high proportion of iGBS (21/41, 51.2%). The most frequent ST was ST19 (18/120, 15.0%), followed by ST2 (17/120, 14.2%). Serotype III/ST17 was predominant in iGBS (12/41, 29.3%), and all 17 ST2 strains were noninvasive. The distribution of most of the investigated virulence factors was not significantly related to invasiveness; noteworthily, most of the serotype III/ST17 iGBS carried pilus island (PI) 2b (10/12, 83.3%), and the prevalence of fbsB was significantly low compared with noninvasive GBS isolates (P = 0.004). Characteristically, the combination of bca(+)-cspA(+)-pavA(+)-fbsB(-)-rib(+)-bac(-) was predominant in iGBS (24.4%, 10/41). Conclusions Serotype III/ST17 GBS carrying PI-2b was frequently detected in iGBS. There was no significant association between invasiveness and the pattern of virulence factors; however, a specific combination of virulence factors was predominant in iGBS.

Abstract Background Maternal rectovaginal colonization by group B Streptococcus (GBS) increases the risk of perinatal GBS disease that can lead to death or long-term neurological impairment. Factors that increase the risk of rectovaginal GBS carriage are incompletely understood resulting in missed opportunities for detecting GBS in risk-based clinical approaches. There is a lacking consensus on whether gestational diabetes mellitus (GDM) is a risk factor for rectovaginal GBS. This systematic review and meta-analysis aims to address current conflicting findings and determine whether GDM should be clinically considered as a risk factor for maternal GBS colonization. Methods Peer-reviewed studies that provided GDM prevalence and documented GBS vaginal and/or rectal colonization in women with and without GDM were included in this analysis. From study inception to October 30, 2023, we identified 6,275 relevant studies from EMBASE and PUBMED of which 19 were eligible for inclusion. Eligible studies were analyzed and thoroughly assessed for risk of bias with a modified Newcastle-Ottawa Scale that interrogated representativeness and comparability of cohorts, quality of reporting for GDM and GBS status, and potential bias from other metabolic diseases. Results were synthesized using STATA 18 and analyzed using random-effects meta-analyses. Results Studies encompassed 266,706 women from 10 different countries, with study periods spanning from 1981 to 2020. Meta-analysis revealed that gestational diabetes is associated with a 16% increased risk of rectovaginal GBS carriage (OR 1.16, CI 1.07–1.26, P = 0.003). We also performed subgroup analyses to assess independent effects of pregestational vs. gestational diabetes on risk of maternal GBS carriage. Pregestational diabetes (Type 1 or Type 2 diabetes mellitus) was also associated with an increased risk of 76% (pooled OR 1.76, CI 1.27–2.45, P = 0.0008). Conclusions This study achieved a consensus among previously discrepant observations and demonstrated that gestational diabetes and pregestational diabetes are significant risk factors for maternal rectovaginal carriage of GBS. Recognition of GDM as a risk factor during clinical decisions about GBS screening and intrapartum antibiotic prophylaxis may decrease the global burden of GBS on maternal-perinatal health.

Introduction: Group B Streptococcus (GBS) or Streptococcus agalactiae is one of the main causes of invasive infections such as meningitis and septicemia in infants. Genital colonization with group B streptococci has been related to increased risk of premature delivery, and premature infants are at greater risk of disease. There is limited information about the prevalence of rectovaginal GBS colonization in pregnant women in Iran. The aim of the present study was investigating the prevalence of group B streptococcus colonization in pregnant women in Iran. Methods: Information of this study was attained by searching on databases including PubMed, Google Scholar, Scopus, Web of Science and SID using relevant keywords and without time limit. Then, the studies containing the inclusion criteria were reviewed. The data were analyzed using Comprehensive MetaAnalysis software (Biostat V3). Heterogeneity between studies was investigated with the I2 index and based on the results of heterogeneity, the random effect model was implemented in order to determine the prevalence of GBS in pregnant women. Results: Out of 231 articles, 15 articles were included in the study. The analysis of 15 studies showed that the prevalence of GBS in Iranian pregnant women was 12.2% (95% CI: 9.9-15.1). Conclusion: In order to prevent the invasive neonatal disease, screening for GBS colonization is recommended for pregnant women in 35–37 weeks of gestation. Regarding the lack of preventive strategies for GBS infections in Iran, national guidelines should be established to guide the obstetricians, midwives, and nurses on the prevention of GBS infections.

Abstract Background Maternal Group B Streptococcus (GBS) colonization is influenced by many factors but results are inconsistent. Consideration of antenatal risk factors may help inform decision making on GBS microbiological culture screening where universal screening is not standard of care. We sought to identify independent predictors of GBS colonization at 34–37 weeks gestation incorporating vaginal symptoms, perineal hygiene measures, sexual activity, and a potential novel factor, constipation. Methods In this prospective cross-sectional study, 573 women at 34–37 weeks gestation had an ano-vaginal swab taken and sent for selective culture for GBS. Women were asked about vaginal bleeding, discharge, irritation and candidiasis, antibiotic use during pregnancy, ano-vaginal hygiene practices such as douching and perineal cleansing after toileting, sexual intercourse related activities, and a potential novel factor for GBS carriage, constipation. Maternal basic demographics and obstetric-related characteristics were also collected. Bivariate analyses were performed to identify associates of GBS colonization. All variables with p

We describe group B Streptococcus linked to disease in farmed pigs and wild porcupines in Italy. Occurrence in pigs was attributed to transmission from nonpasteurized bovine milk whey. Antimicrobial-resistance profiles in isolates from porcupines suggest no common source of infection. Our findings expand the known host range for group B Streptococcus disease.

Abstract Purpose Group B Streptococcus (GBS) is the leading cause of invasive infections in newborns. The prevention of GBS neonatal disease relies on the administration of an intrapartum antibiotic prophylaxis to GBS-colonized women. In recent years, rapid intrapartum detection of GBS vaginal colonization using real-time nucleic acid amplification tests (NAATs) emerged as an alternative to antenatal culture screening methods. Methods We compared the performances of two loop-mediated isothermal amplification (LAMP) tests, the Ampliflash® GBS and the PlusLife® GBS tests, to standard culture for GBS detection in vaginal specimens from pregnant women. The study was conducted from April to July 2023 in a French hospital of the Paris area. Results A total of 303 samples were analyzed, including 85 culture-positive samples (28.1%). The Ampliflash® GBS test and the PlusLife® GBS tests gave a result for 100% and 96.3% tests, respectively. The performances of the tests were as follows: sensitivity 87.1% (95% confidence interval (CI) 78.3–92.6) and 98.7% (95% CI 93.0-99.8), specificity 99.1% (95% CI 96.7–99.8), and 91.9% (95% CI 87.3–95.0), respectively. False negative results of the Ampliflash® GBS test correlated with low-density GBS cultures. Time-to-results correlated with GBS culture density only for the PlusLife® GBS test (p

Background: Gerbode defect is an unusual abnormal communication between the left ventricle and the right atrium and is a serious complication of aortic infective endocarditis. Group B Streptococcus is an uncommon cause of infective endocarditis and has a markedly destructive effect on valvular tissue. Acute fistulation between the left ventricle and the right atrium associated with this form of infective endocarditis is a life-threatening, aggressive complication that often requires urgent surgical intervention. However, the identification of actual communication is often extremely difficult. Herein, we describe an unusual case of Gerbode defect resulting from Group B Streptococcus infective endocarditis and discuss the issues surrounding such a rare cardiac defect and such an infection. Case presentation: A 60-year-old man with underlying uncontrolled diabetes mellitus underwent endoscopic retrograde biliary drainage for acute cholangitis. On the 10th postoperative day, the patient developed multiple acute cerebral embolisms. Transthoracic echocardiography demonstrated severe aortic regurgitation and a large mobile vegetation near the tricuspid annulus. No obvious fistula between the left ventricle and the right atrium could be demonstrated. The blood culture examination was positive for Group B Streptococcus. The patient was diagnosed with Group B Streptococcus infective endocarditis, and antibiotic therapy was initiated. Transesophageal echocardiogram performed after referral to our hospital confirmed detachment of the right coronary cusp of the aortic valve from the annulus and an abnormal cavity immediately below the right coronary cusp. Color Doppler imaging finally revealed systolic blood flows from the left ventricle into the right atrium through the cavity. Therefore, we diagnosed the patient with Gerbode defect resulting from Group B Streptococcus infective endocarditis. In addition to aortic valve replacement, defect closure and left ventricular outflow tract repair were successfully performed urgently for severely complicated and uncommon infective endocarditis. The patient was uneventfully discharged without any complications. Conclusions: We reported successful surgical treatment of unusual active IE and Gerbode defect caused by GBS. Careful preoperative echocardiographic work-up is imperative for accurate early diagnosis and successful repair. [ABSTRACT FROM AUTHOR]

• Largest GBS genome sequence sample of Chinese infants. • Baseline data for GBS surveillance and vaccine impact evaluation. Group B Streptococcus (GBS) is a leading cause of morbidity and mortality in young infants worldwide. This study aimed to investigate candidate GBS vaccine targets, virulence factors, and antimicrobial resistance determinants. We used whole-genome sequencing to characterize invasive GBS isolates from infants < 3 months of age obtained from a multicenter population-based study conducted from 2015 to 2021 in China. Overall, seven serotypes were detected from 278 GBS isolates, four (Ia, Ib, III, V) of which accounted for 97.8 %. We detected 30 sequence types (including 10 novel types) that were grouped into six clonal complexes (CCs: CC1, CC10, CC17, CC19, CC23 and CC651); three novel ST groups in CC17 were detected, and the rate of CC17, considered a hyperinvasive neonatal clone complex, was attached to 40.6 % (113/278). A total of 98.9 % (275/278) of isolates harbored at least one alpha-like protein gene. All GBS isolates contained at least one of three pilus backbone determinants and the pilus types PI-2b and PI-1 + PI-2a accounted for 79.8 % of the isolates. The 112 serotype III/CC17 GBS isolates were all positive for hvgA. Most of the isolates (75.2 %) were positive for serine-rich repeat glycoprotein determinants (srr1 or srr2). Almost all isolates possessed cfb (99.6 %), c1IE (100 %), lmb (95.3 %) or pavA (100 %) gene. Seventy-seven percent of isolates harboured more than three antimicrobial resistance genes with 28.4 % (79/278) gyr A quinolone resistance determinants mutation, 83.8 % (233/278) carrying tet cluster genes and 77.3 % (215/278) carrying erm genes which mediated fluoroquinolone, tetracycline and clindamycin resistance, respectively." The findings from this large whole-genome sequence of GBS isolates establish important baseline data required for further surveillance and evaluating the impact of future vaccine candidates. [ABSTRACT FROM AUTHOR]

Introduction: Rupture of the gestational membranes often precedes major pregnancy complications, including preterm labor and preterm birth. One major cause of inflammation in the gestational membranes, chorioamnionitis (CAM) is often a result of bacterial infection. The commensal bacterium Streptococcus agalactiae, or Group B Streptococcus (GBS) is a leading infectious cause of CAM. Obesity is on the rise worldwide and roughly 1 in 4 pregnancy complications is related to obesity, and individuals with obesity are also more likely to be colonized by GBS. The gestational membranes are comprised of several distinct cell layers which are, from outermost to innermost: maternally-derived decidual stromal cells (DSCs), fetal cytotrophoblasts (CTBs), fetal mesenchymal cells, and fetal amnion epithelial cells (AECs). In addition, the gestational membranes have several immune cell populations; macrophages are the most common phagocyte. Here we characterize the effects of palmitate, the most common long-chain saturated fatty acid, on the inflammatory response of each layer of the gestational membranes when infected with GBS, using human cell lines and primary human tissue. Results: Palmitate itself slightly but significantly augments GBS proliferation. Palmitate and GBS co-stimulation synergized to induce many inflammatory proteins and cytokines, particularly IL-1β and matrix metalloproteinase 9 from DSCs, CTBs, and macrophages, but not from AECs. Many of these findings are recapitulated when treating cells with palmitate and a TLR2 or TLR4 agonist, suggesting broad applicability of palmitate-pathogen synergy. Co-culture of macrophages with DSCs or CTBs, upon co-stimulation with GBS and palmitate, resulted in increased inflammatory responses, contrary to previous work in the absence of palmitate. In whole gestational membrane biopsies, the amnion layer appeared to dampen immune responses from the DSC and CTB layers (the choriodecidua) to GBS and palmitate co-stimulation. Addition of the monounsaturated fatty acid oleate, the most abundant monounsaturated fatty acid in circulation, dampened the proinflammatory effect of palmitate. Discussion: These studies reveal a complex interplay between the immunological response of the distinct layers of the gestational membrane to GBS infection and that such responses can be altered by exposure to long-chain saturated fatty acids. These data provide insight into how metabolic syndromes such as obesity might contribute to an increased risk for GBS disease during pregnancy. [ABSTRACT FROM AUTHOR]

Background Maternal colonization by the bacterium Group B streptococcus (GBS) increases risk of preterm birth, a condition that has an important impact on the health of children. However, research studies that quantify the effect of GBS colonization on preterm birth have reported variable estimates of the effect measure. Methods We performed a simulated cohort study of pregnant women to assess how timing of exposure (GBS colonization) assessment might influence results of studies that address this question. We used published data on longitudinal maternal GBS colonization and on the distribution of preterm births by gestational age to inform parameters used in the simulations. Results Assuming that the probability of preterm birth is higher during weeks when pregnant women are colonized by GBS, our results suggest that studies that assess exposure status early during pregnancy are more likely to estimate an association between GBS colonization and preterm birth that is closer to the null, compared with studies that assess exposure either at birth or during gestational weeks matched to preterm births. In sensitivity analyses assuming different colonization acquisition rates and diagnostic sensitivities, we observed similar results. Conclusions Accurate quantification of the effect of maternal GBS colonization on the risk of preterm birth is necessary to understand the full health burden linked to this bacterium. In this study, we investigated one possible explanation, related to the timing of exposure assessment, for the variable findings of previous observational studies. Our findings will inform future research on this question. [ABSTRACT FROM AUTHOR]

Les infections bactériennes graves ont une incidence plus élevée dans la période néonatale qu'à tout autre âge pédiatrique et leur gravité est accrue en l'absence de diagnostic et de traitement précoces. L'incidence est encore plus importante chez les prématurés que chez les nouveau-nés à terme. Les signes cliniques induits sont peu spécifiques et parfois insignifiants, et les biomarqueurs sont peu performants au cours des 24 premières heures de l'infection. Pendant des décennies, cette situation a conduit à traiter trop d'enfants, pendant de longues périodes, avec des antibiotiques à large spectre. Aujourd'hui, le défi consiste à prescrire des traitements ciblés en identifiant les nouveau-nés réellement infectés. Au cours de ces dix dernières années, nous avons assisté à des changements de paradigme majeurs dont il est essentiel de tenir compte. En effet, la prise de conscience croissante de l'impact écologique de l'antibiothérapie précoce, notamment sa contribution à la résistance de certaines bactéries aux antibiotiques, implique de choisir l'antibiotique à spectre le plus étroit et des durées de traitement en adéquation réelle avec les signes d'infection. Parmi les tests biologiques, les plus importants sont les hémocultures. Au moins une hémoculture, réalisée dans des conditions d'asepsie, de volume suffisant (1 à 2 mL) et avec des flacons pédiatriques, doit être effectuée dès que la décision de traiter est prise, avant de débuter toute antibiothérapie. Les bactéries responsables des infections bactériennes néonatales précoces (IBPN) n'ont pas évolué de manière significative au cours des dernières années et restent dominées par les Streptocoques du groupe B et Escherichia coli , qui sont les principales cibles du traitement. Le SGB est largement prédominant chez les enfants nés à terme, mais la proportion d'infections dues à E. coli augmente avec la prématurité. Severe bacterial infections have a higher incidence in the neonatal period than at any other pediatric age. Incidence is even higher in premature babies than in term newborns, and severity is increased in the absence of early diagnosis and treatment. By contrast, clinical signs are nonspecific and sometimes trivial, and biomarkers perform poorly during the first 24 hours of infection. For decades, this has led to having too many children treated for extended periods with broad-spectrum antibiotics. Today, the challenge is to prescribe antibiotics in a targeted way, by identifying truly infected newborns. Over the last ten years, major paradigm shifts have occurred and should be taken into account, as a result of growing awareness of the ecological impact of early antibiotic therapy, notably antibiotic resistance, by choosing the narrowest spectrum antibiotic and stopping antibiotic therapy as soon as the diagnosis of infection has been reasonably ruled out. Among the biological tests, the most important are blood cultures. At least one blood culture, taken under aseptic conditions, of sufficient volume (1 to 2 mL), and using pediatric bottles must be taken as soon as the decision to treat has been made, before starting any antibiotic therapy. The bacteria responsible for early-onset bacterial neonatal infections (EBNI) have not changed significantly over recent years and remain dominated by Group B streptococcus and Escherichia coli , which are the main targets of treatment. GBS is largely predominant in full-term infants, but the proportion of infections due to E. coli increases with prematurity. [ABSTRACT FROM AUTHOR]

• Point estimates of the half-life of transplacental anti-GBS IgG were 23–28 days. • Strong correlation between IgG concentrations at birth and one month of age. • Antibody kinetics may help in defining a correlate of protection against GBS LOD. Capsular polysaccharide (CPS) serotype-specific Immunoglobulin G (IgG) in cord blood has been proposed as a correlate of protection against invasive Group B Streptococcus (iGBS) disease. Although protective levels are required in infants throughout the window of vulnerability up to 3 months of age, little is known regarding the kinetics of GBS-specific IgG over this period. We enrolled 33 healthy infants born to mothers colonized with GBS. We collected cord blood and infant blood samples either at one (21–35 days), two (49–63 days), or three months of age (77–91 days). We measured GBS serotype-specific CPS IgG concentrations and calculated the decay rate using a mixed-effects model. We further explored whether the antibody kinetics were affected by common maternal and infant factors and estimated the correlation between IgG concentration at birth and one, two, and three months of age. The half-life estimate of IgG concentration for homologous and non-homologous GBS serotypes in paired samples with detectable IgG levels at both time points was 27.4 (95 % CI: 23.5–32.9) days. The decay rate did not vary by maternal age (p = 0.7), ethnicity (p = 0.1), gravida (p = 0.1), gestation (p = 0.7), and infant sex (p = 0.1). Predicted IgG titres above the assay lower limit of quantification on day 30 strongly correlated with titres at birth (Spearman correlation coefficient 0.71 [95 % CI: 0.60–0.80]). Our results provide a basis for future investigations into the use of antibody kinetics in defining a serocorrelate of protection against late-onset iGBS disease. [ABSTRACT FROM AUTHOR]

Introduction: Detailed assessment of the population structure of group B Streptococcus (GBS) among adults is still lacking in Saudi Arabia. Here we characterized a representative collection of isolates from colonized and infected adults. Methods: GBS isolates (n=89) were sequenced by Illumina and screened for virulence and antimicrobial resistance determinants. Genetic diversity was assessed by single nucleotide polymorphisms and core-genome MLST analyses. Results: Genome sequences revealed 28 sequence types (STs) and nine distinct serotypes, including uncommon serotypes VII and VIII. Majority of these STs (n=76) belonged to the human-associated clonal complexes (CCs) CC1 (33.71%), CC19 (25.84%), CC17 (11.24%), CC10/CC12 (7.87%), and CC452 (6.74%). Major CCs exhibited intra-lineage serotype diversity, except for the hypervirulent CC17, which exclusively expressed serotype III. Virulence profiling revealed that nearly all isolates (94.38%) carried at least one of the four alpha family protein genes (i.e., alphaC, alp1, alp2/3, and rib), and 92.13% expressed one of the two serine-rich repeat surface proteins Srr1 or Srr2. In addition, most isolates harbored the pilus island (PI)-2a alone (15.73%) or in combination with PI-1 (62.92%), and those carrying PI-2b alone (10.11%) belonged to CC17. Phylogenetic analysis grouped the sequenced isolates according to CCs and further subdivided them along with their serotypes. Overall, isolates across all CC1 phylogenetic clusters expressed Srr1 and carried the PI-1 and PI-2a loci, but differed in genes encoding the alphalike proteins. CC19 clusters were dominated by the III/rib/srr1/PI-1+PI-2a (43.48%, 10/23) and V/alp1/srr1/PI-1+PI-2a (34.78%, 8/23) lineages, whereas most CC17 isolates (90%, 9/10) had the same III/rib/srr2/P1-2b genetic background. Interestingly, genes encoding the CC17-specific adhesins HvgA and Srr2 were detected in phylogenetically distant isolates belonging to ST1212, suggesting that other highly virulent strains might be circulating within the species. Resistance to macrolides and/or lincosamides across all major CCs (n=48) was associated with the acquisition of erm(B) (62.5%, 30/48), erm(A) (27.1%, 13/48), lsa(C) (8.3%, 4/48), and mef(A) (2.1%, 1/48) genes, whereas resistance to tetracycline was mainly mediated by presence of tet(M) (64.18%, 43/67) and tet(O) (20.9%, 14/67) alone or in combination (13.43%, 9/67). Discussion: These findings underscore the necessity for more rigorous characterization of GBS isolates causing infections. [ABSTRACT FROM AUTHOR]

Purpose: To assess Gram-positive bacterial (GPB) bloodstream infection (BSI) in neonates, covering incidence, morbidity, mortality, antimicrobial resistance patterns and biomarkers in Region Stockholm, Sweden between 2006 and 2016. Methods: A population-based retrospective epidemiological study including infants with GPB-BSI, admitted to the neonatal units at Karolinska University Hospital (KUH). Data were collected from patient records, the Swedish Neonatal Quality Register, the microbiological laboratory at KUH and the Swedish Public Health Agency. Results: We identified 357 infants with GPB-BSI, representing an incidence of 1.47/1000 live births (LB). Group B streptococcus (GBS) was the most common pathogen causing BSI in full-term infants and early-onset sepsis (EOS) (0.20/1000 LB), while coagulase-negative staphylococci (CoNS) were predominant in infants born very preterm and in late-onset sepsis (LOS) (0.79/1000 LB). There were no fatal GBS BSI cases, but 10.2% developed meningitis. The GPB case fatality rate was 9.5% and the sepsis fatality rate 2.8%. In GPB-BSI, 1/10 did not have an elevated C-reactive protein level. Staphylococcus aureus (S. aureus) BSI increased during the study period, but no methicillin or vancomycin resistant strains were found. The antimicrobial resistance (AMR) rate was highest in CoNS isolates. Conclusion: GPB-BSI was four times more common than Gram-negative BSI in neonates but resulted in lower mortality rate. GBS was the most common pathogen in full-term infants and in EOS. CoNS was the most common pathogen in LOS and infants born very preterm, and the AMR rate was high in these isolates. The increasing trend of S. aureus BSI indicates a need of further investigation. [ABSTRACT FROM AUTHOR]

Aim: To determine the prevalence of group B Streptococcus (GBS) carriage among parturient women and neonates, and the relative risk of vertical transmission, the relative risk of early and late‐onset GBS and the pooled incidence of early‐late‐onset GBS infection. Methods: A systematic search of relevant cohort studies from three electronic databases to identify all relevant studies published up to 7 November 2022. The review was conducted in accordance with PRISMA guidelines. Estimates were pooled using random‐effects meta‐analyses. Results: A total of 54 articles with 355 787 matched pairs of parturient women and neonates from 30 countries were included in the analysis. The pooled prevalence of GBS colonisation was 17.1% among the pregnant women and 1.0% among neonates. The pooled prevalence of vertical transmission of GBS was 4.5% and the pooled relative risk of GBS colonisation of neonates born to mothers with GBS was 9.9. Conclusion: We support the implementation of targeted intrapartum antibiotic prophylaxis for all women who are positive for GBS as well as women with risks factors for early onset GBS in their infants regardless of their GBS colonisation status. [ABSTRACT FROM AUTHOR]

Aim: Clusters of group B Streptococcus (GBS) infections in neonatal intensive care units (NICU) are poorly documented. We aimed to assess GBS cross‐transmission during an outbreak of GBS sepsis. Methods: The study was carried out between October and November 2021 in a French University Hospital. Neonatal intensive care unit (NICU) patients with GBS sepsis were included. Clinical data were retrieved from electronic patient records. Group B Streptococcus isolates were characterized at the molecular level using capsular genotyping and whole‐genome sequencing (WGS). Results: The outbreak of GBS sepsis affected three very preterm neonates with a gestational age of less than 26 weeks, including one recurrent male index case aged 26 days, and two female secondary cases aged 5 and 17 days. The microbiological investigation identified a GBS isolate of capsular type III and Sequence Type 17 as responsible for the four infectious episodes. Whole‐genome sequencing confirmed the identity between the isolates. The outbreak and the results of the microbiological investigations led to an immediate reinforcement of hygiene measures. Conclusion: Clustered cases of GBS infections in NICU and horizontal transmission of the hypervirulent GBS Sequence Type 17 are likely underestimated. Prospective investigation of all nosocomial cases using WGS should contribute to improving vigilance regarding GBS cross‐transmission and infection prevention. [ABSTRACT FROM AUTHOR]

Background: Group B Streptococcus (GBS) transmitted from colonized pregnant women to the newborns is considered the leading cause of neonatal sepsis with high mortality rate, so screening pregnant women for GBS colonization is important for intrapartum antibiotic prophylaxis to prevent neonatal and maternal infections, this study aimed to detect the prevalence of GBS colonization in pregnant women and to assess the diagnostic value of GeneXpert PCR assay in screening. Methods: Rectovaginal swabs from 318 pregnant women with gestational age 35 or more weeks were tested by conventional culture as a standard screening method and by GeneXpert PCR assay as a rapid molecular method. Results: The prevalence of GBS colonization in pregnant women was 17% by standard culture method and 22% by the GeneXpert PCR assay with overall 98.2% sensitivity, 93.6% specificity, 94.3% diagnostic accuracy and total turnaround time less than 1 hour. Conclusion: The increase in prevalence of GBS colonization of pregnant women raises the concern about importance of the accurate and rapid molecular diagnostic techniques for effective prevention of GBS transmission. [ABSTRACT FROM AUTHOR]

Background and rationale: Group B Streptococcus (GBS) is a Gram-positive, nonmotile, encapsulated bacterium classified under Lancefield group B antigen. Predominantly found in the gastrointestinal and genitourinary tracts. GBS is a leading cause of invasive bacterial diseases in neonates, including neonatal sepsis, meningitis, septicemia, and pneumonia. Aim: To study the vaginal colonization rate of Streptococcus agalactiae and virulence genes in pregnant women with adverse pregnancy outcome. Methods: A cross-sectional study was designed included 200 pregnant women at 34-37 weeks of gestation. A total of two hundred vaginal swabs were taken from all pregnant women enrolled in this project by the gynecologist. GBS isolated bacteria was evaluated by means of using classical microbiological approaches. After DNA extraction, the isolated GBS strains were screened for the presence of cfb and scpB gene by polymerase chain reaction. Results: Thirty-six (18%) of 200 pregnant women enrolled in this project were positive for group B Streptococcus by culture methods. The majority were 18-36 years old, 20 (20.6%) had a history of abortion, and 10 (9.9%) had rupture membranes of >18 hours. The particular PCR primer detected scpB and cfb genes. The scpB gene was discovered in 17 (47%), whereas the cfb gene was detected in 31 (86%). Conclusion: There is no statistical significance between repeated abortions with the presence of scpB and cfb genes as a virulence factor in GBS while there is statistical significance between the presence of these virulence genes and rupture membranes. [ABSTRACT FROM AUTHOR]

Group B Streptococcus (GBS) is a major cause of contagious bovine mastitis (CBM) in Brazil. The GBS population is composed of host-generalist and host-specialist lineages, which may differ in antimicrobial resistance (AMR) and zoonotic potential, and the surveillance of bovine GBS is crucial to developing effective CBM control and prevention measures. Here, we investigated bovine GBS isolates (n = 156) collected in Brazil between 1987 and 2021 using phenotypic testing and whole-genome sequencing to uncover the molecular epidemiology of bovine GBS. Clonal complex (CC) 61/67 was the predominant clade in the 20th century; however, it was replaced by CC91, with which it shares a most common recent ancestor, in the 21st century, despite the higher prevalence of AMR in CC61/67 than in CC91, and high selection pressure for AMR from indiscriminate antimicrobial use in the Brazilian dairy industry. CC103 also emerged as a dominant CC in the 21st century, and a considerable proportion of herds had two or more GBS strains, suggesting poor biosecurity and within-herd evolution due to the chronic nature of CBM problems. The majority of bovine GBS belonged to serotype Ia or III, which was strongly correlated with CCs. Ninety-three isolates were resistant to tetracycline (≥8 μg/mL; tetO = 57, tetM = 34 or both = 2) and forty-four were resistant to erythromycin (2.0 to >4 μg/mL; ermA = 1, ermB = 38, mechanism unidentified n = 5). Only three isolates were non-susceptible to penicillin (≥8.0 μg/mL), providing opportunities for improved antimicrobial stewardship through the use of narrow-spectrum antimicrobials for the treatment of dairy cattle. The common bovine GBS clades detected in this study have rarely been reported in humans, suggesting limited risk of interspecies transmission of GBS in Brazil. This study provides new data to support improvements to CBM and AMR control, bovine GBS vaccine design, and the management of public health risks posed by bovine GBS in Brazil. [ABSTRACT FROM AUTHOR]

We present a case of endogenous endophthalmitis with urinary tract infection (UTI) caused by group B Streptococcus (GBS). An 86-year-old female initially presented with ocular pain and sudden visual disturbance of the left eye. The patient did not complain of other symptoms and had no history of recent ocular surgery or trauma. Endogenous endophthalmitis was clinically diagnosed based on ophthalmic examination, history, and lab results showing systemic infection. A few days later, GBS was identified in her aqueous humor, blood, and urine cultures. Intravitreal ceftazidime and vancomycin injections, as well as fortified ceftazidime and vancomycin eye drops, were used immediately after clinical diagnosis. However, the symptoms worsened despite repeated intravitreal injections, so evisceration was performed. Endogenous endophthalmitis caused by GBS is very virulent and may present without evident systemic symptoms. The early recognition of the disease and systemic work up, followed by prompt treatment, is necessary. [ABSTRACT FROM AUTHOR]

Purpose: Group B Streptococcus (GBS) is the leading cause of invasive infections in newborns. The prevention of GBS neonatal disease relies on the administration of an intrapartum antibiotic prophylaxis to GBS-colonized women. In recent years, rapid intrapartum detection of GBS vaginal colonization using real-time nucleic acid amplification tests (NAATs) emerged as an alternative to antenatal culture screening methods. Methods: We compared the performances of two loop-mediated isothermal amplification (LAMP) tests, the Ampliflash® GBS and the PlusLife® GBS tests, to standard culture for GBS detection in vaginal specimens from pregnant women. The study was conducted from April to July 2023 in a French hospital of the Paris area. Results: A total of 303 samples were analyzed, including 85 culture-positive samples (28.1%). The Ampliflash® GBS test and the PlusLife® GBS tests gave a result for 100% and 96.3% tests, respectively. The performances of the tests were as follows: sensitivity 87.1% (95% confidence interval (CI) 78.3–92.6) and 98.7% (95% CI 93.0-99.8), specificity 99.1% (95% CI 96.7–99.8), and 91.9% (95% CI 87.3–95.0), respectively. False negative results of the Ampliflash® GBS test correlated with low-density GBS cultures. Time-to-results correlated with GBS culture density only for the PlusLife® GBS test (p < 0.001). Conclusion: Both techniques provide excellent analytical performances with high sensitivity and specificity together with a short turnaround time and results available in 10 to 35 min. Their potential to further reduce the burden of GBS neonatal disease compared with antenatal culture screening needs to be assessed in future clinical studies. [ABSTRACT FROM AUTHOR]

ABSTRACT Group B Streptococcus (GBS) is a pathobiont responsible for invasive infections in neonates and the elderly. The transition from a commensal to an invasive pathogen relies on the timely regulation of virulence factors. In this study, we characterized the role of the SaeRS two-component system in GBS pathogenesis. Loss-of-function mutations in the SaeR response regulator decrease virulence in mouse models of invasive infection by hindering the ability of bacteria to persist at the inoculation site and to spread to distant organs. Transcriptome and in vivo analysis reveal a specialized regulatory system specifically activated during infection to control the expression of only two virulence factors: the PbsP adhesin and the BvaP secreted protein. The in vivo surge in SaeRS-regulated genes is complemented by fine-tuning mediated by the repressor of virulence CovRS system to establish a coordinated response. Constitutive activation of the SaeRS regulatory pathway increases PbsP-dependent adhesion and invasion of epithelial and endothelial barriers, though at the cost of reduced virulence. In conclusion, SaeRS is a dynamic, highly specialized regulatory system enabling GBS to express a restricted set of virulence factors that promote invasion of host barriers and allow these bacteria to persist inside the host during lethal infection.IMPORTANCEGroup B Streptococcus (or GBS) is a normal inhabitant of the human gastrointestinal and genital tracts that can also cause deadly infections in newborns and elderly people. The transition from a harmless commensal to a dangerous pathogen relies on the timely expression of bacterial molecules necessary for causing disease. In this study, we characterize the two-component system SaeRS as a key regulator of such virulence factors. Our analysis reveals a specialized regulatory system that is activated only during infection to dynamically adjust the production of two virulence factors involved in interactions with host cells. Overall, our findings highlight the critical role of SaeRS in GBS infections and suggest that targeting this system may be useful for developing new antibacterial drugs.

Summary: Background: Early-onset Group B Streptococcus (EOGBS) infection leads to substantial morbidity and mortality in newborn infants. Intrapartum antibiotic prophylaxis (IAP) prevents EOGBS infection, but IAP strategies vary. The approach to the provision of IAP can be risk-based, universal or a combination of the two strategies. Previous systematic reviews reported that universal strategies might be most optimal in lowering EOGBS infection, but there is no consensus. Therefore, we aimed to provide up-to-date evidence on effectiveness of different strategies by comparing perinatal outcomes. Methods: A systematic search for EOGBS prevention strategies was performed in MEDLINE, Embase and Web of Science on May 2024. Studies were included if they reported on different strategies and outcomes of interest, including EOGBS infection, IAP administration and antimicrobial resistance regardless of publication date. Summary data was extracted from published reports. Study quality was assessed using the ROBINS-I tool. Random-effects meta-analyses were used to determine risk ratios (RR) and 95%-confidence intervals. PROSPERO registration CRD42023411806. Findings: A total of 6293 records were identified, of which 72 observational studies were included for synthesis with more than 10 million live births. Meta-analysis demonstrated that implementation of any strategy (n = 34 studies, RR 0.46 (0.36–0.60)), risk-based strategies (n = 11 studies, RR 0.65 (0.48–0.87)), or universal strategies (n = 16 studies, RR 0.37 (0.25–0.55)) was associated with a reduced risk of EOGBS infection compared to no strategy. In direct comparison, universal strategies were associated with a reduced risk of EOGBS compared to a risk-based strategy (n = 17 studies, RR 0.41 (0.30–0.55)), while the proportion of women receiving IAP did not differ between risk-based (16%) and universal (21%) strategies (n = 9 studies, RR 1.29 (0.95–1.75)). There was no antimicrobial resistance of EOGBS isolates to penicillin or ampicillin (n = 11 studies). Interpretation: Any IAP strategy could reduce the risk of EOGBS infection without evidence of increasing antimicrobial resistance. Universal strategies give the largest reduction in the EOGBS burden, while not exposing a significantly higher proportion of pregnancies to IAP compared to risk-based strategies. Funding: UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction, a cosponsored programme executed by the World Health Organization.

ObjectivesCertain Group B Streptococcus (GBS) genotypes are associated with invasive disease in neonates. We conducted a comparative genomic analysis of GBS isolates from neonatal disease and maternal carriage in the Netherlands to determine distribution of genetic markers between the two host groups.MethodsWhole genome sequencing was used to characterise 685 neonatal invasive isolates (2006–2021) and 733 maternal carriage isolates (2017–2021) collected in the Netherlands.ResultsClonal complex (CC) 17 and serotype III were significantly more common in disease while carriage isolates were associated with serotypes II, IV, V as well as CC1. Previously reported CC17-A1 sub-lineage was dominant among disease isolates and significantly less common in carriage. The phiStag1 phage, previously associated with expansion of invasive CC17 isolates in the Netherlands, was more common among disease isolates compared to carriage isolates overall, however it was equally distributed between CC17 isolates from carriage and disease. Prevalence of antimicrobial resistance genes was overall lower in disease compared to carriage isolates, but increased significantly over time, mediated by rise in prevalence of a multidrug resistance element ICESag37 among disease isolates.ConclusionThere is a stable association between certain GBS genotypes and invasive disease, which suggests opportunities for developing more precise disease prevention strategies based on GBS targeted screening. In contrast, GBS mobile genetic elements appear less likely to be correlated with carriage or disease, and instead are associated with clonal expansion events across the GBS population.

Reproductive tract infections in antenatal women are frequently occurring public health concern affecting the quality of life in the infected women and further affects the neonatal outcome negatively. Vaginal infections are predominantly caused due to the disturbance in the normal vaginal microflora. Group B Streptococcus (GBS) is a major peritoneal pathogen leading to morbidity and mortality in both mother and neonates leading to complications like preterm labour, chorioamnionitis and Preterm rupture of membrane (PROM). Further, Vulvovaginal candidiasis (VVC) is a frequently encountered gynaecological disease causing morbidity in 3/4th of women at least once in their life span. It leads to infertility in non-pregnant women. It results in adverse pregnancy outcomes such as chorioamnionitis and congenital abnormalities in the neonates. The aim of this study is to screen for potential bacterial and yeast infections with focus on GBS and Candida infections and its neonatal outcome. Candida species and GBS were identified by routine culture-based tests. HiChrome agar was used for speciation of Candida species. CAMP test was performed for GBS; further identification was done using Streptococcal grouping kit. GBS was found in 15% of the antenatal women and Candida Species was found to be most common with an infection rate of 50%. Lower segment Cesarean section (LSCS) rate in GBS positive women was 60% and in Candida Non albicans positive women was found to be 65.38%. 33% of the neonates born to GBS positive mothers had respiratory distress. Infection in antenatal women negatively influenced the mode of delivery and the mean body weight of the neonates born to infected mothers were comparatively less.

Abstract Neonatal clinical sepsis is recognized as a significant health problem, This study sought to identify a predictive model of risk factors for clinical neonatal sepsis. A retrospective study was conducted from 1 October 2018 to 31 March 2023 in a large tertiary hospital in China. Neonates were divided into patients and controls based on the occurrence of neonatal sepsis. A multivariable model was used to determine risk factors and construct models.The utilization and assessment of model presentation were conducted using Norman charts and web calculators, with a focus on model differentiation, calibration, and clinical applicability (DCA). Furthermore, the hospital’s data from 1 April 2023 to 1 January 2024 was utilized for internal validation. In the modelling dataset, a total of 339 pairs of mothers and their newborns were included in the study and divided into two groups: patients (n = 84, 24.78%) and controls (n = 255, 75.22%). Logistic regression analysis was performed to examine the relationship between various factors and outcome. The results showed that maternal age

Abstract Knowing about the antibiotic resistance, serotypes, and virulence-associated genes of Group B Streptococcus for epidemiological and vaccine development is very important. We have determined antimicrobial susceptibility patterns, serotype, and virulence profiles. The antibiotic susceptibility was assessed for a total of 421 Streptococcus agalactiae strains, isolated from pregnant women and neonates. Then, 89 erythromycin and/or clindamycin-resistant strains (82 isolates obtained from pregnant women and seven isolates derived from neonates) were assessed in detail. PCR techniques were used to identify the studied strains, perform serotyping, and assess genes encoding selected virulence factors. Phenotypic and genotypic methods determined the mechanisms of resistance. All tested strains were sensitive to penicillin and levofloxacin. The constitutive MLSB mechanism (78.2%), inducible MLSB mechanism (14.9%), and M phenotype (6.9%) were identified in the macrolide-resistant strains. It was found that macrolide resistance is strongly associated with the presence of the ermB gene and serotype V. FbsA, fbsB, fbsC, scpB, and lmb formed the most recurring pattern of genes among the nine surface proteins whose genes were analysed. A minority (7.9%) of the GBS isolates exhibited resistance to lincosamides and macrolides, or either, including those that comprised the hypervirulent clone ST-17. The representative antibiotic resistance pattern consisted of erythromycin, clindamycin, and tetracycline resistance (71.9%). An increase in the fraction of strains resistant to macrolides and lincosamides indicates the need for monitoring both the susceptibility of these strains and the presence of the ST-17 clone.

Background Group B streptococcus (GBS) remains a leading cause of infant sepsis, meningitis and death despite intrapartum antibiotic prophylaxis. A vaccine is urgently required, and two candidates are in advanced clinical trials. For successful GBS vaccine implementation, especially if a vaccine is licensed based on an immunological threshold, there must be cross-sector engagement, effective advocacy, robust plans for phase IV studies and equitable access. Meeting A round-table discussion, held at St George’s University of London, reviewed the current position of GBS vaccines in the UK context, focusing on phase IV plans, convening a diverse group of stakeholders from across the UK, with a role in GBS vaccine licensure, advocacy, implementation or effectiveness evaluation. Presentations outlined the latest UK epidemiology, noting the rising infant invasive GBS (iGBS) infection rates from 1996 to 2021 for both early and late onset disease, with the highest disease rates in Black infants (1.1/1000 livebirths vs white infants (0.81/1000 livebirths). Potential coverage of the candidate vaccines was high (>95%). Regulatory input suggested that EU regulators would consider waiving the need for a pre-licensure efficacy study if a putative correlate of protection could be adequately justified. Phase IV study methodologies for a GBS vaccine were considered, largely based on previous UK maternal vaccine assessments, such as a nationwide cohort study design using a vaccine register and a maternal services dataset. Other strategies were also discussed such as a cluster or stepped-wedge randomised trial to evaluate implementation outcomes. Opportunities for advocacy, education and engagement with additional key partners were discussed and identified. Conclusions With an approved GBS vaccine a near possibility, planning of phase IV studies and identification of critical barriers to implementation are urgently needed. Cross-sector engagement is essential and will facilitate a successful pathway.

Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is a predominant pathogen of neonatal sepsis, commonly associated with early-onset neonatal sepsis. GBS has also been associated with cases of late-onset sepsis potentially originating from the intestine. Previous findings have shown GBS can colonize the infant intestinal tract as part of the neonatal microbiota. To better understand GBS colonization dynamics in the neonatal intestine, we collected stool and milk samples from prematurely born neonates for identification of potential pathogens in the neonatal intestinal microbiota. GBS was present in approximately 10% of the cohort, and this colonization was not associated with maternal GBS status, delivery route, or gestational weight. Interestingly, we observed the relative abundance of GBS in the infant stool negatively correlated with maternal IgA concentration in matched maternal milk samples. Using a preclinical murine model of GBS infection, we report that both vertical transmission and direct oral introduction resulted in intestinal colonization of GBS; however, translocation beyond the intestine was limited. Finally, vaccination of dams prior to breeding induced strong immunoglobulin responses, including IgA responses, which were associated with reduced mortality and GBS intestinal colonization. Taken together, we show that maternal IgA may contribute to infant immunity by limiting the colonization of GBS in the intestine.

ABSTRACTSix serotypes (Ia, Ib, II, III, IV, and V) cause nearly all group B streptococcal (GBS) disease globally. Capsular polysaccharide (CPS) conjugate vaccines aim to prevent GBS disease, however, licensure of a vaccine would depend on a standardized serological assay for measuring anti-CPS IgG responses. A multiplex direct Luminex-based immunoassay (dLIA) has been developed to simultaneously measure the concentration of serum IgG specific for the six prevalent GBS CPS serotypes. Assay validation was performed using serum samples obtained from human subjects vaccinated with an investigational 6-valent GBS CPS conjugate vaccine. Results for the assay are expressed as IgG concentrations (µg/mL) using a human serum reference standard composed of pooled sera from vaccinated subjects. The lower limits of quantitation (LLOQ) for all serotypes covered in the 6-plex GBS IgG dLIA fell within the range of 0.002-0.022 µg/mL IgG. Taken together, the 6-plex GBS IgG dLIA platform is specific for the six GBS serotypes included in Pfizer’s investigational vaccine, has a wide dilution adjusted assay range, and is precise (

ABSTRACTMeasurement of IgG antibodies against group B streptococcus (GBS) capsular polysaccharide (CPS) by use of a standardized and internationally accepted multiplex immunoassay is important for the evaluation of candidate maternal GBS vaccines in order to compare results across studies. A standardized assay is also required if serocorrelates of protection against invasive GBS disease are to be established in infant sera for the six predominant GBS serotypes since it would permit the comparison of results across the six serotypes. We undertook an interlaboratory study across five laboratories that used standardized assay reagents and protocols with a panel of 44 human sera to measure IgG antibodies against GBS CPS serotypes Ia, Ib, II, III, IV, and V. The within-laboratory intermediate precision, which included factors like the lot of coated beads, laboratory analyst, and day, was generally below 20% relative standard deviation (RSD) for all six serotypes, across all five laboratories. The cross-laboratory reproducibility was