Neonatal Group B Streptococcus Research Articles

Neonatal Group B Streptococcus infection at a single center in Al-Madinah Al-Munawarah, Saudi Arabia.

To determine the occurrence of Group B Streptococcus (GBS) infection in neonates and its associated risk factors in Al-Madinah Al-Munawarah, Saudi Arabia. This retrospective study was carried out at the Maternity and Child Hospital in Al-Madinah Al-Munawarah, between 2017-2022. The laboratory and clinical data of 64 neonates were collected and analyzed using GraphPad Prism 7 software. Out of 16,022 neonates admitted to the nursery, 64 infants were diagnosed with GBS infection. Approximately 53.1% were male, 46.9% female, 15.6% were preterm, and 84.4% were full-term. Vaginal births accounted for 71.9%. The mean onset age was 10±12.4 days. Among the GBS patients, 53.1% had early-onset disease (EOD, 0-6 days), while 46.9% had late-onset disease (LOD, 7-90 days). Unexamined mothers had a higher incidence of GBS and EOD newborns (p=0.05). Meningitis was more common in LOD than EOD patients and correlated with illness onset (p=0.05). Early-onset disease patients had a higher incidence of sepsis. The mortality rate was 10.9%, while 89.1% were discharged from the hospital. Neonatal GBS infection is prevalent in Al-Madinah Al-Munawarah. Several risk factors may contribute to the occurrence of GBS infection including preterm labor, higher body temperature during delivery, prolonged premature rupture of membranes for more than 18 hours, and GBS bacteriuria. We recommend that larger multi-centric studies are needed in Al-Madinah Al-Munawarah, to study the magnitude of neonatal GBS infection and risk factors to develop a screening protocol in maternity and children's hospital.

Cervicovaginal Microbial-Immune State and Group B Streptococcus Colonization in Pregnancy.

Maternal colonization with Group B Streptococcus (GBS) is a significant risk factor for serious neonatal morbidity. There are limited data on how the cervicovaginal (CV) microbiota and host immune factor β-defensin-2 might influence GBS colonization in pregnant individuals. This study sought to determine if the CV microbiota is associated with GBS colonization in pregnant individuals, and if β-defensin-2 modifies this relationship. This was a secondary analysis of a prospective cohort study of pregnant individuals with singleton pregnancies who had CV microbiota specimens analyzed at 16 to 20, 20 to 24, and 24 to 28 weeks' gestation, along with a third trimester GBS rectovaginal (RV) culture (n = 492). Microbiota data were analyzed with 16S rRNA gene sequencing and classified into community state types (CSTs). Log-binomial multivariable regression was used to model associations between CST and GBS RV status and to calculate risk ratios. β-defensin-2, an immune factor known to modulate the relationship between CST and pregnancy outcomes, was examined as an effect modifier. Of 492 individuals, 34.3% were GBS RV + . Compared with individuals with CST I at 16 to 20 weeks, individuals with CST IV-A and CST II had a significantly elevated relative risk of subsequent GBS RV+ status. When stratified by high and low β-defensin-2 levels, β-defensin-2 was found to be an effect modifier of the association between CST IV-A and GBS RV+ status. In individuals with low β-defensin-2 levels, CST VI-A was associated with GBS RV+ status, but among individuals with high β-defensin-2 levels, there was no such association (interaction p-value = 0.03). Pregnant individuals with CV microbiota characterized by CST IV-A and CST II had significantly elevated risk of GBS RV colonization in the third trimester compared with those with CST I, and β-defensin-2 was an effect modifier of the association between CST IV-A and GBS RV+ status. Future research should investigate if manipulation of the CV microbiota can prevent GBS colonization, thereby reducing intrapartum antibiotic prophylaxis and the risks of neonatal GBS infection. · The relationship between the CV microbiota and GBS RV colonization is unknown.. · A Lactobacillus-deficient, anaerobic rich vaginal community, CST IV-A, is associated with increased risk of GBS RV colonization.. · β-defensin-2 is an effect modifier of the association between CST IV-A and GBS RV+ status..

Exploring the Feasibility of Intrapartum GBS Collection to Identify Residual GBS in a Pilot Study of an Antenatal Probiotic Intervention

(1) Background: We aimed to explore the feasibility of collecting intrapartum maternal Group B Streptococcus (GBS) colonization and immediate post-birth neonatal GBS colonization cultures for use in a larger trial and to identify cases of residual GBS, which were hypothesized to be less common in the probiotics group. (2) Methods: This sub-study added additional outcome measures to the parent study to identify intrapartum and neonatal colonization and compare between probiotic and placebo groups and to identify cases of residual GBS. Intrapartum maternal vaginal and rectal GBS cultures were collected at the time of admission to a hospital for labor and to give birth. Neonatal oral and nasopharynx GBS cultures were collected within 1–2 h of giving birth. (3) Results: Thirty intrapartum samples were collected; twenty-eight had complete data. The antepartum GBS results significantly predicted the intrapartum results (p = 0.005), with 86.7% of cultures remaining the same at both time points. There were four cases where the intrapartum GBS results were different to the 36-week antepartum cultures results. A case of residual GBS was identified in one probiotic group participant. None of the neonatal swabs were positive for GBS. No cases of EOGBSD occurred in infants born to the study participants. (4) Conclusions: Although the 36–37 week GBS results significantly predicted the intrapartum results, the utility for a larger research trial on probiotics to reduce antenatal GBS is unclear. Intrapartum GBS swab collection was feasible in a busy nurse, midwife, and physician practice. GBS was not recovered from neonatal oral and nasopharyngeal swabs. The pathways of neonatal GBS colonization require further study.

Long-term surveillance of group B Streptococcus strains isolated from infection and colonization in pregnant women and newborns.

Introduction. Group B Streptococcus (GBS) remains the leading cause of bacterial neonatal infections worldwide, despite the spread of recommendations on vaginal screening and antibiotic prophylaxis.Hypothesis/Gap Statement. There is a need to evaluate the potential changes in GBS epidemiology over time following the introduction of such guidelines.Aim. Our aim was to perform a descriptive analysis of the epidemiological characteristics of GBS by conducting a long-term surveillance of strains isolated between 2000 and 2018, using molecular typing methods.Methodology. A total of 121 invasive strains, responsible for maternal infections (20 strains), fetal infections (8 strains) and neonatal infections (93 strains), were included in the study, representing all the invasive isolates during the period; in addition, 384 colonization strains isolated from vaginal or newborn samples were randomly selected. The 505 strains were characterized by capsular polysaccharide (CPS) type multiplex PCR assay and the clonal complex (CC) was assigned using a single nucleotide polymorphism PCR assay. Antibiotic susceptibility was also determined.Results. CPS types III (32.1 % of the strains), Ia (24.6 %) and V (19 %) were the most prevalent. The five main CCs observed were CC1 (26.3 % of the strains), CC17 (22.2 %), CC19 (16.2 %), CC23 (15.8 %) and CC10 (13.9 %). Neonatal invasive GBS diseases were predominantly due to CC17 isolates (46.3 % of the strains), which mainly express CPS type III (87.5 %), with a very high prevalence in late-onset diseases (76.2 %).Conclusion. Between 2000 and 2018, we observed a decrease in the proportion of CC1 strains, which mainly express CPS type V, and an increase in the proportion of CC23 strains, mainly expressing CPS type Ia. Conversely, there was no significant change in the proportion of strains resistant to macrolides, lincosamides or tetracyclines. The two molecular techniques used in our study provide almost as much information as classical serotyping and multilocus sequence typing, but are quicker, easy to perform, and avoid long sequencing and analysis steps.

Calibration of a serum reference standard for Group B streptococcal polysaccharide conjugate vaccine development using surface plasmon resonance

Group B streptococcus (GBS) is a leading cause of neonatal morbidity and mortality worldwide. Development of a maternal vaccine to protect newborns through placentally transferred antibody is considered feasible based on the well-established relationship between anti-GBS capsular polysaccharide (CPS) IgG levels at birth and reduced risk of neonatal invasive GBS. An accurately calibrated serum reference standard that can be used to measure anti-CPS concentrations is critical for estimation of protective antibody levels across serotypes and potential vaccine performance. For this, precise weight-based measurement of anti-CPS IgG in sera is required. Here, we report an improved approach for determining serum anti-CPS IgG levels using surface plasmon resonance with monoclonal antibody standards, coupled with a direct Luminex-based immunoassay. This technique was used to quantify serotype-specific anti-CPS IgG levels in a human serum reference pool derived from subjects immunized with an investigational six-valent GBS glycoconjugate vaccine.

Population genetics of group B Streptococcus from maternal carriage in an ethnically diverse community in London.

Maternal immunization against Group B Streptococcus (GBS) has the potential to significantly reduce the burden of neonatal GBS infections. Population genetics of GBS from maternal carriage can offer key insights into vaccine target distribution. In this study we characterized the population structure of GBS isolates from maternal carriage (n = 535) in an ethnically diverse community in London, using whole genome sequencing. The isolates clustered into nine clonal complexes (CCs) but the majority (95%) belonged to five lineages: CC1 (26%), CC19 (26%), CC23 (20%), CC17 (13%) and CC8/10 (10%). Nine serotypes were identified, the most common were serotypes III (26%), V (21%), II (19%) and Ia (19%). Other serotypes (Ib, IV, VI, VII, IX) represented less than 10% of all isolates each. Intra-lineage serotype diversity was observed in all major CCs but was highest in CC1, which revealed nine serotypes. Nearly all isolates (99%) carried at least one of the four alpha family protein genes (alpha, alp1, alp23, and rib). All isolates were susceptible to penicillin. We found 21% and 13% of isolates to be resistant to clarithromycin and clindamycin, respectively. Prevalence of macrolide-lincosamide-streptogramin B (MLSB) resistance genes was 22% and they were most common in CC19 (37%) and CC1 (28%), and isolates with serotypes V (38%) and IV (32%). We identified some associations between maternal ethnicity and GBS population structure. Serotype Ib was significantly less common among the South Asian compared to Black women (S. Asian: 3/142, Black: 15/135, p = 0.03). There was also a significantly lower proportion of CC1 isolates among the White other (24/142) in comparison to Black (43/135) and S. Asian (44/142) women (p = 0.04). We found a significantly higher proportion of CC17 isolates among the White other compared to S. Asian women (White other: 32/142, S. Asian: 10/142, p = 0.004). Our study showed high prevalence of GBS vaccine targets among isolates from pregnant women in London. However, the observed serotype diversity in CC1 and high prevalence of MLSB resistance genes in CC19 demonstrates presence of high risk lineages, which might act as a reservoir of non-vaccine strains and antimicrobial resistance determinants.

Recent research on the epidemiology and preventive strategies of neonatal group B Streptococcus infection in the latest decade

Currently, the main strategy for preventing neonatal group B Streptococcus (GBS) infection is prenatal screening combined with intrapartum antibiotic prophylaxis, which has effectively reduced the incidence of neonatal GBS early-onset disease. However, the burden of GBS infection is still significant. The intrapartum antibiotic prophylaxis strategy has limitations such as inducing antibiotic resistance and inability to effectively prevent GBS late-onset disease. It is crucial to develop and evaluate other prevention strategies, while paying close attention to assessing penicillin allergy in pregnant women and how to prevent GBS infection in neonates with negative maternal GBS screening. In recent years, there has been some progress in GBS vaccines and related immunological research, and the use of specific vaccines is expected to significantly reduce GBS infection in neonates.

Interspecies Interactions within the Host: the Social Network of Group B Streptococcus.

Group B Streptococcus (GBS) is a pervasive neonatal pathogen accounting for a combined half a million deaths and stillbirths annually. The most common source of fetal or neonatal GBS exposure is the maternal microbiota. GBS asymptomatically colonizes the gastrointestinal and vaginal mucosa of 1 in 5 individuals globally, although its precise role in these niches is not well understood. To prevent vertical transmission, broad-spectrum antibiotics are administered to GBS-positive mothers during labor in many countries. Although antibiotics have significantly reduced GBS early-onset neonatal disease, there are several unintended consequences, including an altered neonatal microbiota and increased risk for other microbial infections. Additionally, the incidence of late-onset GBS neonatal disease remains unaffected and has sparked an emerging hypothesis that GBS-microbe interactions in developing neonatal gut microbiota may be directly involved in this disease process. This review summarizes our current understanding of GBS interactions with other resident microbes at the mucosal surface from multiple angles, including clinical association studies, agriculture and aquaculture observations, and experimental animal model systems. We also include a comprehensive review of in vitro findings of GBS interactions with other bacterial and fungal microbes, both commensal and pathogenic, along with newly established animal models of GBS vaginal colonization and in utero or neonatal infection. Finally, we provide a perspective on emerging areas of research and current strategies to design microbe-targeting prebiotic or probiotic therapeutic intervention strategies to prevent GBS disease in vulnerable populations.

Not Just an Intrapartum Problem: Late-Onset Group B Streptococcus Disease.

Group B streptococcal (GBS) infection is a leading cause of neonatal morbidity and mortality globally. While prevention strategies for early onset GBS disease are well established, methods to prevent late-onset GBS disease do not eliminate disease burden, leaving potential for infection, and devastating consequences for affected neonates. Furthermore, the incidence of late-onset GBS has risen in recent years, with preterm infants at the highest risk of infection and death. Meningitis remains the most common and serious complication associated with late onset disease, occurring in 30 percent of cases. The assessment of risk for neonatal GBS infection should not be limited to the birth process or maternal screening results and intrapartum antibiotic prophylaxis treatment status. Horizontal transmission after birth from mothers, caregivers, and community sources has been observed. Late-onset GBS disease and its sequelae remain a significant risk to neonates, and clinicians should be able to recognize the signs and symptoms to provide timely antibiotic therapy. This article discusses of the pathogenesis, risk factors, clinical manifestations, diagnostics, and treatment of neonatal late-onset GBS infection and identifies implications for practicing clinicians.

Invasive Group B Streptococcus Infection and Early Complement Deficiency

Group B Streptococcus (GBS) is a well-known cause of invasive disease in newborns. Although neonatal GBS infection does not often prompt immunologic work-up, history of invasive GBS infection may suggest an underlying early complement deficiency.

NEONATAL GROUP B STREPTOCOCCAL DISEASE IN A NEONATAL INTENSIVE CARE UNIT: A TWELVE-YEAR STUDY

Introduction: Group B Streptococcus (GBS) is a gram-positive coccus, that frequently colonizes the human genital and gastrointestinal tract, and is the most common cause of invasive infections in neonates. The high clinical suspicion and early treatment are essential to prevent devastating sequelae and improve the prognosis of these patients. Materials and Methods: A retrospective descriptive study made with children younger than 3 months of age, admitted to a neonatal intensive care unit of a level II hospital, from January 1, 2010 to December 31, 2021, with early (EOI) or late-onset (LOI) neonatal GBS infection. Reviewed obstetric history, risk factors, intrapartum chemoprophylaxis (IPA), clinical manifestations, antibiotic therapy, supportive care, recurrent infection, morbidities and deaths. Results: There were 6 cases registered during 12-year period with GBS infection, 3(50%) had EOI, 3(50%) had LOI and 1 case with recurrent infection (more 2 episodes). Most cases were prematures (4/6; 67%)with average gestational age of 29weeks. Eight GBS infections were documented. In EOI, prematurity and prolonged rupture of membranes without chemoprophylaxis were identified as risk factors. The most common clinical diagnosis was meningitis (62,5%, 5/8) and sepsis/bacteriemia without a focus (37,5%, 3/8). The most used empirical therapy was ampicillin, gentamicin and cefotaxime (50%, 4/8) and the most frequent definitive therapy was Penicillin G. 4 patients needed ventilatory support and 1 needed shock and seizures treatment. In one case hydrocephalus and delayed psychomotor development (DPD) were reported and in another case DPD and eyelid ptosis were also reported. 1 death occurred. Conclusion: In our study, maternal colonization wasn’t a risk factor for EIO, because the 4 mothers who performed GBS culture (2 mothers of term newborns and 2 mothers of preterms, one with invasive disease and other with recurrent infection) were negative. We obtained a higher percentage of meningitis than previously described (62.5% vs 5-10%), probably because most patients were premature and immunosuppressed.

Neonatal invasive disease caused by Streptococcus agalactiae in Europe: the DEVANI multi-center study.

Group B streptococcus (GBS) remains a leading cause of invasive disease, mainly sepsis and meningitis, in infants < 3months of age and of mortality among neonates. This study, a major component of the European DEVANI project (Design of a Vaccine Against Neonatal Infections) describes clinical and important microbiological characteristics of neonatal GBS diseases. It quantifies the rate of antenatal screening and intrapartum antibiotic prophylaxis among cases and identifies risk factors associated with an adverse outcome. Clinical and microbiological data from 153 invasive neonatal cases (82 early-onset [EOD], 71 late-onset disease [LOD] cases) were collected in eight European countries from mid-2008 to end-2010. Respiratory distress was the most frequent clinical sign at onset of EOD, while meningitis is found in > 30% of LOD. The study revealed that 59% of mothers of EOD cases had not received antenatal screening, whilst GBS was detected in 48.5% of screened cases. Meningitis was associated with an adverse outcome in LOD cases, while prematurity and the presence of cardiocirculatory symptoms were associated with an adverse outcome in EOD cases. Capsular-polysaccharide type III was the most frequent in both EOD and LOD cases with regional differences in the clonal complex distribution. Standardizing recommendations related to neonatal GBS disease and increasing compliance might improve clinical care and the prevention of GBS EOD. But even full adherence to antenatal screening would miss a relevant number of EOD cases, thus, the most promising prophylactic approach against GBS EOD and LOD would be a vaccine for maternal immunization.

Group B Streptococcus and Pregnancy: Critical Concepts and Management Nuances

Group B Streptococcus (GBS) is a common pathogen with an effective treatment. However, it remains a significant cause of neonatal sepsis, morbidity, and mortality. The screening and management of this infection are some of the first concepts learned during medical training in obstetrics. However, effective screening and evidence-based management of GBS are nuanced with many critical caveats. The objectives of this review are to discuss the essential aspects of GBS screening and management and to highlight recent changes to recommendations and guidelines. Original research articles, review articles, and guidelines on GBS were reviewed. The following recommendations are based on review of the evidence and professional society guidelines. Screening for GBS should occur between 36 weeks and the end of the 37th week. The culture swab should go 2 cm into the vagina and 1 cm into the anus. Patients can perform their own swabs as well. Penicillin allergy testing has been shown to be safe in pregnancy. Patients with GBS in the urine should be treated at term with antibiotic prophylaxis, independent of the colony count of the culture. Patients who are GBS-positive with preterm and prelabor rupture of membranes after 34 weeks are not candidates for expectant management, as this population has higher rates of neonatal infectious complications. Patients with a history of GBS colonization in prior pregnancy who are GBS-unknown in this current pregnancy and present with labor should receive intrapartum prophylaxis. Work on the GBS vaccine continues. Although all of the efforts and focus on neonatal early-onset GBS infection have led to lower rates of disease, GBS still remains a major cause of neonatal morbidity and mortality requiring continued vigilance from obstetric providers.

Maternal Group B Streptococcal Rectovaginal Colonization after Intrapartum Antibiotic Prophylaxis.

Maternal rectovaginal colonization with Group B Streptococcus (GBS) during labor is a prerequisite for neonatal early-onset GBS disease. Intrapartum antibiotic prophylaxis (IAP) has been proven to prevent GBS perinatal infection, while there are few studies on the evaluation of the effectiveness of different antibiotic prophylaxis regimens. This study aimed to assess the maternal rectovaginal GBS colonization status after IAP, antimicrobial susceptibility and maternal and neonatal outcomes among women administered different antibiotic prophylaxis regimens. A prospective study was conducted between June 2018 and June 2022. GBS carriers identified at 35-37 weeks of gestation were provided IAP (penicillin, cefazolin or clindamycin) at delivery based on the local protocol for GBS prevention. Rectovaginal samples were obtained from participants again after delivery. Antimicrobial susceptibility testing in GBS isolates was performed using the broth microdilution method. A total of 295 cases were included in this study. In the postpartum re-examination for GBS, the overall negative rectovaginal culture rate was 90.8% (268/295). Women who received cefazolin prophylaxis had the highest negative culture rate (95.2%, 197/207), which was followed by those who received penicillin (80.7%, 67/83) and clindamycin (80.0%, 4/5) (p = 0.001). All GBS isolates achieved sensitivity to penicillin and cefazolin, whereas resistance to clindamycin was shown in 21.4% of the strains. There were no significant differences in maternal and neonatal outcomes among the IAP groups. The use of IAP is highly effective in reducing the maternal rectovaginal GBS colonization. Cefazolin may offer equivalent efficacy and safety compared to standard penicillin prophylaxis.

Comparative Analysis of the Molecular Characteristics of Group B Streptococcus Isolates Collected from Pregnant Korean Women Using Whole-genome Sequencing.

The incidence of early- and late-onset sepsis and meningitis in neonates due to maternal rectovaginal group B Streptococcus (GBS) colonization may differ with serotype distribution and clonal complex (CC). CC17 strains are associated with hypervirulence and poor disease outcomes. GBS serotypes are distinguished based on the polysaccharide capsule, the most important virulence factor. We determined the sequence type distribution of GBS isolates from pregnant women in Korea and validated whole-genome sequencing (WGS)-based prediction of antimicrobial susceptibility and capsular serotypes in GBS isolates. Seventy-five GBS isolates collected from pregnant Korean women visiting Wonju Severance Christian Hospital, Wonju, Korea between 2017 and 2019 were subjected to WGS using the NovaSeq 6000 system (Illumina, San Diego, CA, USA). Multilocus sequence types, serotypes, antimicrobial resistance genes, and hemolysin operon mutations were determined by WGS, and the latter three were compared with the results of conventional phenotypic methods. The predominant lineage was CC1 (37.3%), followed by CC19 (32.0%), CC12 (17.3%), and CC17 (4.0%). All isolates were cps typeable (100%, (75/75), and 89.3% of cps genotypes (67/75) were concordant with serotypes obtained using latex agglutination. The cps genotypes of the 75 isolates were serotypes III (24.0%), V (22.7%), and VIII (17.3%). All isolates harboring intact ermB and tet were non-susceptible to erythromycin and tetracycline, respectively. Three non-hemolytic strains had 1-bp frameshift insertions in cylE. The low prevalence of CC17 GBS colonization may explain the low frequency of neonatal GBS infections. WGS is a useful tool for simultaneous genotyping and antimicrobial resistance determination.

Group B Streptococcus among Pregnant Women and Neonates in Saudi Arabia: A Systemic Review.

Sepsis caused by Group B Streptococcus (GBS) continues to cause mortality and morbidity in newborns, especially in developing countries. Bacterial sepsis in newborns varies nationally and even within countries. Developing countries have reported 34 deaths per 1000 live births compared to 5 in developed countries. This systemic review aimed to assess the prevalence of GBS colonization among pregnant women and the incidence of neonatal GBS sepsis in Saudi Arabia. A literature search of PubMed, MEDLINE Ovid, and Google Scholar was conducted. A total of 21 studies were found: 15 described maternal GBS colonization and 6 studies described neonatal GBS infections. The GBS colonization prevalence among pregnant women ranged from 2.1% to 32.8%. Inconsistencies in the reporting method for neonatal GBS infection rates were observed. Only two studies have the incidence of neonatal GBS as the primary outcome. No national multicenter studies exist on the GBS rates among neonates. Nationwide studies are warranted to assess the burden of GBS infections in neonates. These studies would guide appropriate GBS screening strategies during pregnancy for application in a national public health program.

The Group B Streptococcal Adhesin BspC Interacts with Host Cytokeratin 19 To Promote Colonization of the Female Reproductive Tract.

ABSTRACTStreptococcus agalactiae, otherwise known as Group B Streptococcus (GBS), is an opportunistic pathogen that vaginally colonizes approximately one third of healthy women. During pregnancy, this can lead to in utero infection, resulting in premature rupture of membranes, chorioamnionitis, and stillbirths. Furthermore, GBS causes serious infection in newborns, including sepsis, pneumonia, and meningitis. Previous studies have indicated that GBS antigen (Ag) I/II family proteins promote interaction with vaginal epithelial cells; thus, we hypothesized that the Ag I/II Group B streptococcal surface protein C (BspC) contributes to GBS colonization of the female reproductive tract (FRT). Here, we show that a ΔbspC mutant has decreased bacterial adherence to vaginal, ecto-, and endocervical cells, as well as decreased auto-aggregation and biofilm-like formation on cell monolayers. Using a murine model of vaginal colonization, we observed that the ΔbspC mutant strain exhibited a significant fitness defect compared to wild-type (WT) GBS and was less able to ascend to the cervix and uterus in vivo, resulting in reduced neutrophil chemokine signaling. Furthermore, we determined that BspC interacts directly with the host intermediate filament protein cytokeratin 19 (K19). Surface localization of K19 was increased during GBS infection, and interaction was mediated by the BspC variable (V) domain. Finally, mice treated with a drug that targets the BspC V-domain exhibited reduced bacterial loads in the vaginal lumen and reproductive tissues. These results demonstrate the importance of BspC in promoting GBS colonization of the FRT and that it may be targeted therapeutically to reduce GBS vaginal persistence and ascending infection.

Population genomics of Group B Streptococcus reveals the genetics of neonatal disease onset and meningeal invasion

Group B Streptococcus (GBS), or Streptococcus agalactiae, is a pathogen that causes preterm births, stillbirths, and acute invasive neonatal disease burden and mortality. Here, we investigate bacterial genetic signatures associated with disease onset time and meningeal tissue infection in acute invasive neonatal GBS disease. We carry out a genome-wide association study (GWAS) of 1,338 GBS isolates from newborns with acute invasive disease; the isolates had been collected annually, for 30 years, through a national bacterial surveillance program in the Netherlands. After controlling for the population structure, we identify genetic variation within noncoding and coding regions, particularly the capsule biosynthesis locus, statistically associated with neonatal GBS disease onset time and meningeal invasion. Our findings highlight the impact of integrating microbial population genomics and clinical pathogen surveillance, and demonstrate the effect of GBS genetics on disease pathogenesis in neonates and infants.

Vertical Transmission, Risk Factors, and Antimicrobial Resistance Patterns of Group B Streptococcus among Mothers and Their Neonates in Southern Ethiopia.

Background Group B Streptococcus (GBS) contributes to maternal and neonatal morbidity and mortality by increasing intrauterine infection or vertical transmission at the time of birth. Despite many efforts to reduce the potential risk of vertical transmission, GBS remains the main cause of serious disease (neonatal sepsis, meningitis, and/or pneumonia) in vulnerable newborns during the first week of life. This study aimed to assess vertical transmission, risk factors, and antimicrobial resistance patterns of GBS among pregnant women and their neonates. Methods A facility-based cross-sectional study was conducted among mothers and their neonates from February to May 2021. A total of 201 pregnant women with their neonates participated in this study. A well-designed questionnaire was used to collect sociodemographic and clinical data. A vaginal swab from mother before delivery and neonatal nasal and ear canal swab samples were taken as soon as after delivery within 30 minutes. Vaginal swabs, neonatal ear canal, and nasal swabs were placed into Todd–Hewitt broth and incubated at 37°C for 18–24 hours at 35–37°C in 5% CO2 conditions and then subcultured on 5% sheep blood agar for 18–48 hours. Presumptive identification of GBS was made by morphology, Gram stain, catalase, and hemolytic activity on sheep blood agar plates. CAMP and bacitracin susceptibility tests were used as confirmatory tests for GBS. Data were analyzed using SPSS version 21. P value ≤0.05 was considered statistically significant. Results Vertical transmission rates of GBS (mother to neonates) were 11.9%. The prevalence of GBS among pregnant women and newborns was 24/201 (11.9%) (95% CI = 7.5–16.9) and 11/201 (5.5%) (95% CI = 2.5–9.0), respectively. The history of prolonged rupture of membranes (AOR = 3.5, CI = 2.2–18.8) and urinary tract infection (AOR = 2.9, CI = 1.7–16.3) were associated factors for maternal GBS colonization. Gestational age of <37 weeks (p=0.008), low birth weight of <2.5 kg (p=0.001), and maternal history of vaginal discharge (p=0.048) were associated factors for neonatal GBS colonization. Low antibiotic resistance was observed for erythromycin 8.6%, clindamycin 5.7%, and chloramphenicol 2.9%. Conclusion In this study, high vertical transmission (mother to neonates) rate was observed. The prevalence of vaginal GBS colonization of women at delivery was 11.9% and significantly associated with the history of prolonged rupture of membranes and urinary tract infections. Gestational age of <37 weeks, low birth weight of <2.5 kg, and maternal history of vaginal discharge were associated with neonatal GBS colonization. Hence, there is a need for antenatal culture-based GBS screening, risk factor-based interventions, and regular follow-up of drug resistance patterns for proper treatment and management of GBS.

Screening of group B Streptococcus infection in pregnancy and neonatal outcomes in the province of Trento, Italy.

The study analyzes the trend of group B streptococcal (GBS) infection in pregnancy in the province of Trento, Italy, where a universal screening of GBS infection in pregnancy has been active for some time. Data from pregnant women who gave birth at local maternity units between 2015-2019 were obtained from birth attendance certificates (BAC), the main - and mandatory - source of information for monitoring pregnancies, births and neonatal health in Italy. The BAC used in the province of Trento acquires the results of a vast range of infections in pregnancy. The data collected from the BAC were integrated with those provided by the Hospital Information System (SIO). The occurrence of neonatal GBS infection was investigated on 2019 birth cohort, using the hospital discharge archive as an ancillary information source. Between 2015-2019, 20,905 pregnant women received care at maternity units of the province of Trento, Italy, of whom 25.5% were foreigners. The average coverage of GBS testing in pregnancy was 91.8% (95% CI 91.25-92.35) without significant variations from one year to the next. Test coverage varies in relation to maternity units and some socio-demographic characteristics of mothers. The average proportion of GBS positive cases over the study period was 21.0% (95% CI 20.7-21.3), a value that does not show statistically significant changes from one year to the next. The proportion of positive cases appears uneven among the subgroups of pregnant women considered, even if the differences are not statistically significant. In the 2019 birth cohort, newborns to GBS-positive mothers had an excess of stillbirths, of those born with Apgar at 5 minutes <7 and hospitalized at birth. However, these excesses were not statistically significant. Intravenous Antibiotic Prophylaxis (IAP) was performed in 86.8% of births from GBS positive mothers who had an indication for IAP. IAP was inadequate in 7.4% of the GBS positive mothers. Postnatal evaluation of 783 live births to GBS positive mothers identified 3 cases of early neonatal GBS infection. The incidence of neonatal GBS infection over the whole series of live births is 0.71/1,000 (95% CI 0.56-0.86), 0.68/1000 (CI 95% 0.55-0.79) in Italians and 1.07/1000 (95% CI 0.45-1.65) in foreigners. Data collection on infections in pregnancy through BAC allows area-based assessment. The quality of the data recorded in the BAC can be considered satisfactory but it was necessary to access to other information sources. The local availability of various information sources should allow periodic audits and closer monitoring of neonatal GBS infection.