Genomic and phenotypic characterisation of invasive neonatal and colonising group B Streptococcus isolates from Slovenia, 2001–2018

Abstract Background Group B Streptococcus (GBS) is the leading cause of invasive neonatal disease in the industrialized world. We aimed to genomically and phenotypically characterise invasive GBS isolates in Slovenia from 2001 to 2018 and contemporary colonising GBS isolates from screening cultures in 2018. Methods GBS isolates from 101 patients (invasive isolates) and 70 pregnant women (colonising isolates) were analysed. Basic clinical characteristics of the patients were collected from medical records. Antimicrobial susceptibility and phenotypic capsular serotype were determined. Whole-genome sequencing was performed to assign multilocus sequence types (STs), clonal complexes (CCs), pathogenicity/virulence factors, including capsular genotypes, and genome-based phylogeny. Results Among invasive neonatal disease patients, 42.6% (n = 43) were females, 41.5% (n = 39/94) were from preterm deliveries (< 37 weeks gestation), and 41.6% (n = 42) had early-onset disease (EOD). All isolates were susceptible to benzylpenicillin with low minimum inhibitory concentrations (MICs; ≤0.125 mg/L). Overall, 7 serotypes were identified (Ia, Ib, II-V and VIII); serotype III being the most prevalent (59.6%). Twenty-eight MLST STs were detected that clustered into 6 CCs. CC-17 was the most common CC overall (53.2%), as well as among invasive (67.3%) and non-invasive (32.9%) isolates (p < 0.001). CC-17 was more common among patients with late-onset disease (LOD) (81.4%) compared to EOD (47.6%) (p < 0.001). The prevalence of other CCs was 12.9% (CC-23), 11.1% (CC-12), 10.5% (CC-1), 8.2% (CC-19), and 1.8% (CC-498). Of all isolates, 2.3% were singletons. Conclusions A high prevalence of hypervirulent CC-17 isolates, with low genomic diversity and characteristic profile of pathogenicity/virulence factors, was detected among invasive neonatal and colonising GBS isolates from pregnant women in Slovenia. This is the first genomic characterisation of GBS isolates in Slovenia and provides valuable microbiological and genomic baseline data regarding the invasive and colonising GBS population nationally. Continuous genomic surveillance of GBS infections is crucial to analyse the impact of IND prevention strategies on the population structure of GBS locally, nationally, and internationally.

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Biomarkers for a histological chorioamnionitis diagnosis in pregnant women with or without group B streptococcus infection: a case-control study

BMC Pregnancy and Childbirth ◽

10.1186/s12884-021-03731-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jie Ren ◽

Zhe Qiang ◽

Yuan-yuan Li ◽

Jun-na Zhang

Keyword(s):

Cord Blood ◽

Pregnant Women ◽

Peripheral Blood ◽

Group B Streptococcus ◽

Diagnostic Value ◽

Adverse Outcomes ◽

Intercellular Adhesion Molecule ◽

Tnf Α ◽

Group B ◽

The Impact

Abstract Background Chorioamnionitis may cause serious perinatal and neonatal adverse outcomes, and group B streptococcus (GBS) is one of the most common bacteria isolated from human chorioamnionitis. The present study analyzed the impact of GBS infection and histological chorioamnionitis (HCA) on pregnancy outcomes and the diagnostic value of various biomarkers. Methods Pregnant women were grouped according to GBS infection and HCA detection. Perinatal and neonatal adverse outcomes were recorded with a follow-up period of 6 weeks. The white blood cell count (WBC), neutrophil ratio, and C-reactive protein (CRP) level from peripheral blood and soluble intercellular adhesion molecule-1 (sICAM-1), interleukin 8 (IL-8), and tumor necrosis factor α (TNF-α) levels from cord blood were assessed. Results A total of 371 pregnant women were included. Pregnant women with GBS infection or HCA had a higher risk of pathological jaundice and premature rupture of membranes and higher levels of sICAM-1, IL-8, and TNF-α in umbilical cord blood. Univariate and multivariate regression analysis revealed that sICMA-1, IL-8, TNF-α, WBC, and CRP were significantly related to an increased HCA risk. For all included pregnant women, TNF-α had the largest receiver operating characteristic (ROC) area (area: 0.841; 95% CI: 0.778–0.904) of the biomarkers analyzed. TNF-α still had the largest area under the ROC curve (area: 0.898; 95% CI: 0.814–0.982) for non-GBS-infected pregnant women, who also exhibited a higher neutrophil ratio (area: 0.815; 95% CI: 0.645–0.985) and WBC (area: 0.849; 95% CI: 0.72–0.978), but all biomarkers had lower value in the diagnosis of HCA in GBS-infected pregnant women. Conclusion GBS infection and HCA correlated with several perinatal and neonatal adverse outcomes. TNF-α in cord blood and WBCs in peripheral blood had diagnostic value for HCA in non-GBS-infected pregnant women but not GBS-infected pregnant women.

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Poor Adherence to the Screening-Based Strategy of Group B Streptococcus Despite Colonization of Pregnant Women in Greece

Pathogens ◽

10.3390/pathogens10040418 ◽

2021 ◽

Vol 10 (4) ◽

pp. 418

Author(s):

Maria Maroudia Berikopoulou ◽

Aikaterini Pana ◽

Theodota Liakopoulou-Tsitsipi ◽

Nikos F. Vlahos ◽

Vasiliki Papaevangelou ◽

...

Keyword(s):

Risk Factors ◽

Risk Factor ◽

Pregnant Women ◽

Late Onset ◽

Group B Streptococcus ◽

Culture Collection ◽

Carrier Status ◽

Cross Sectional ◽

Screening Guidelines ◽

Group B

Group B streptococcus (GBS) is a leading cause of serious neonatal infections. Maternal GBS colonization is associated with early- and late-onset neonatal disease (EOD/LOD). In Greece, a screening-based strategy is recommended, in which concurrent vaginal-rectal cultures should be obtained between 36 0/7 and 37 6/7 weeks’ gestation. We sought to examine the level of adherence to the GBS screening guidelines and estimate the prevalence of GBS colonization among pregnant women. Although in Greece the screening-based strategy is followed, we also examined known EOD risk factors and linked them to GBS colonization. A cross-sectional study of 604 women postpartum in three hospitals and maternity clinics was conducted. Following written informed consent, data were collected via a short self-completed questionnaire and review of patients’ records. In 34.6% of the enrolled pregnant women, no culture had been taken. Of the remaining, 12.8% had proper vaginal-rectal sample collections. The overall maternal colonization rate was 9.6%. At least one risk factor for EOD was identified in 12.6% of participants. The presence of risk factors was associated with positive cultures (p = 0.014). The rate of culture collection did not differ between women with or without an EOD risk factor. Adherence to a universal screening of pregnant women with vaginal-rectal cultures was poor. Despite probable underestimation of GBS carrier status, almost 1 in 10 participants were GBS positive during pregnancy. Screening of women with risk factors for EOD should, at least, be prioritized to achieve prevention and prompt intervention of EOD.

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The impact of group B streptococcus prophylaxis on late-onset neonatal infections

Journal of Perinatology ◽

10.1038/jp.2012.76 ◽

2012 ◽

Vol 33 (3) ◽

pp. 206-211 ◽

Cited By ~ 10

Author(s):

K L Ecker ◽

P K Donohue ◽

K S Kim ◽

J A Shepard ◽

S W Aucott

Keyword(s):

Late Onset ◽

Group B Streptococcus ◽

Neonatal Infections ◽

Group B ◽

The Impact

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Analysis of virulence factors and antibiotic resistance genes in Group B Streptococcus from clinical samples

10.21203/rs.2.21004/v1 ◽

2020 ◽

Author(s):

Raymond Mudzana ◽

Rooyen T Mavenyengwa ◽

Muchaneta Gudza-Mugabe

Keyword(s):

Antibiotic Resistance ◽

Pregnant Women ◽

Virulence Factors ◽

Resistance Genes ◽

Virulence Genes ◽

Group B Streptococcus ◽

Antibiotic Resistance Genes ◽

Virulence Gene ◽

Clinical Samples ◽

Group B

Abstract Background: Streptococcus agalacticae is one of the most important causative agents of serious infections among neonates. Group B Streptococcus (GBS) virulence factors are important in the development of vaccines, whilst antibiotic resistance genes are necessary in understanding the resistance mechanisms used by these pathogens. This study was carried out to identify the virulence genes and antibiotic resistance genes associated with GBS isolated from pregnant women.Methods: A total of 43 GBS isolates were obtained from vaginal samples that were collected from all HIV positive and HIV negative women who were 13-35 weeks pregnant attending Antenatal Care at both Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods including molecular tests. Antibiotic susceptibility testing using 3 antibiotics was done using the modified Kirby-Bauer method. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes in the isolates. Data was fed into SPSS 24.0 and the Spearman rank correlation test used to determine any correlation among genes.Results: Nine distinct virulence gene profiles were identified. The profiles hly-scpB-bca-rib 37.2% (16/43) and hly-scpB-bca 18.6% (8/43) were common among GBS isolates. The following virulence gene frequencies were obtained namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). Antibiotic resistance genes showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene amplification yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded a low 9.3% (4/43).Conclusion: The study showed a high prevalence of multiple virulence genes hly, scpB, bca and rib in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was found to be predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

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Perinatal hormones favor CC17 group B Streptococcus intestinal translocation through M cells and hypervirulence in neonates

eLife ◽

10.7554/elife.48772 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 1

Author(s):

Constantin Hays ◽

Gérald Touak ◽

Abdelouhab Bouaboud ◽

Agnès Fouet ◽

Julie Guignot ◽

...

Keyword(s):

Late Onset ◽

Group B Streptococcus ◽

Intestinal Barrier ◽

Surface Protein ◽

Neonatal Infection ◽

M Cells ◽

M Cell ◽

Hormonal Exposure ◽

Group B ◽

The Impact

Group B Streptococcus (GBS) is the leading cause of invasive bacterial neonatal infections. Late-onset diseases (LOD) occur between 7 and 89 days of life and are largely due to the CC17 GBS hypervirulent clone. We studied the impact of estradiol (E2) and progesterone (P4), which impregnate the fetus during pregnancy, on GBS neonatal infection in cellular and mouse models of hormonal exposure corresponding to concentrations found at birth (E2-P4 C0) and over 7 days old (E2-P4 C7). Using representative GBS isolates, we show that E2-P4 C7 concentrations specifically favor CC17 GBS meningitis following mice oral infection. CC17 GBS crosses the intestinal barrier through M cells. This process mediated by the CC17-specific surface protein Srr2 is enhanced by E2-P4 C7 concentrations which promote M cell differentiation and CC17 GBS invasiveness. Our findings provide an explanation for CC17 GBS responsibility in LOD in link with neonatal gastrointestinal tract maturation and hormonal imprint.

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Streptococcus agalactiae colonization and screening approach in high-risk pregnant women in southern Brazil

The Journal of Infection in Developing Countries ◽

10.3855/jidc.12025 ◽

2020 ◽

Vol 14 (04) ◽

pp. 332-340

Author(s):

Jeane Zanini da Rocha ◽

Jéssica Feltraco ◽

Vanessa Radin ◽

Carla Vitola Gonçalves ◽

Pedro Eduardo Almeida da Silva ◽

...

Keyword(s):

High Risk ◽

Pregnant Women ◽

Low Cost ◽

Group B Streptococcus ◽

Neonatal Morbidity ◽

Neonatal Infection ◽

Diagnostic Methods ◽

Antenatal Screening ◽

Group B ◽

The Impact

Introduction: Considering that Group B Streptococcus (GBS) persists as an important cause of neonatal morbidity and mortality, the objective of this study was to evaluate the frequency of maternal colonization by GBS, comparing the culture by the Granada broth with the GeneXpert real-time PCR diagnostic methods and the impact of chemoprophylaxis in high-risk pregnant women. Methodology: A prospective cohort of 110 pregnant women hospitalized for gestational complications was formed and recruited following interview and collection of rectovaginal swabs. Results: The frequency of maternal colonization was 28.2% and statistically associated with Capurro> 37 weeks (p = 0.030) and neonatal infection (p = 0.008). Chemoprophylaxis was offered to 80% of those colonized. Among the pregnant women treated, a fivefold reduction in the rate of prematurity and rate of neonatal infection was observed. The sensitivity was 76.6% and 86.6% in culture and PCR, respectively, with an optimal index of agreement between the methods (K = 0.877). Grenade culture was considered an easy and low-cost method, while GeneXpert presented higher cost and error rate of 10%. However, 23.3% of the pregnant women were diagnosed exclusively by GeneXpert and the results were obtained in two hours. Conclusions: This study showed a significant prevalence of maternal colonization for GBS and that both culture and molecular methods had peculiarities that allow different applicability, with the culture being feasible for antenatal screening and in the hospital for high-risk pregnant women with no sign of imminent delivery and GeneXpert being prioritized for situations of preterm birth.

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Prevalence, Risk Factors, and Serotype Distribution of Group B Streptococcus Colonization in HIV-Infected Pregnant Women Living in Belgium: A Prospective Cohort Study

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy320 ◽

2018 ◽

Vol 5 (12) ◽

Cited By ~ 2

Author(s):

Nicolas Dauby ◽

Catherine Adler ◽

Veronique Y Miendje Deyi ◽

Rosalie Sacheli ◽

Laurent Busson ◽

...

Keyword(s):

Risk Factors ◽

Pregnant Women ◽

Late Onset ◽

Group B Streptococcus ◽

Neonatal Infection ◽

Colonization Rate ◽

Vaccine Serotypes ◽

Related Data ◽

Significant Difference ◽

Group B

Abstract Background Group B streptococcus (GBS) infection is a leading cause of severe neonatal infection. Maternal GBS carriage during pregnancy is the main risk factor for both early-onset and late-onset GBS disease. High incidence of GBS infection has been reported in HIV-exposed but -uninfected infants (HEU). We aimed to determine the prevalence, characteristics, and risk factors for GBS colonization in HIV-infected and HIV-uninfected pregnant women living in Belgium. Methods Between January 1, 2011, and December 31, 2013, HIV-infected (n = 125) and -uninfected (n = 120) pregnant women had recto-vaginal swabs at 35–37 weeks of gestation and at delivery for GBS detection. Demographic, obstetrical, and HIV infection–related data were prospectively collected. GBS capsular serotyping was performed on a limited number of samples (33 from HIV-infected and 16 from HIV-uninfected pregnant women). Results There was no significant difference in the GBS colonization rate between HIV-infected and -uninfected pregnant women (29.6% vs 24.2%, respectively). HIV-infected women were more frequently colonized by serotype III (36.4% vs 12.5%), and the majority of serotype III strains belonged to the hypervirulent clone ST-17. Exclusively trivalent vaccine serotypes (Ia, Ib, and III) were found in 57.6% and 75% of HIV-infected and -uninfected women, respectively, whereas the hexavalent vaccine serotypes (Ia, Ib, II, III, IV, and V) were found in 97% and 100%, respectively. Conclusions HIV-infected and -uninfected pregnant women living in Belgium have a similar GBS colonization rate. A trend to a higher colonization rate with serotype III was found in HIV-infected women, and those serotype III strains belong predominantly to the hypervirulent clone ST17.

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High prevalence of Group B Streptococcus colonization among pregnant women in amman, jordan

American Journal of Obstetrics and Gynecology ◽

10.1016/j.ajog.2017.08.035 ◽

2017 ◽

Vol 217 (6) ◽

pp. 739

Author(s):

Kate Clouse ◽

Asem Shehabi ◽

Abel Mani Suleimat ◽

Samir Faouri ◽

Najwa Khuri-Bulos ◽

...

Keyword(s):

Pregnant Women ◽

Group B Streptococcus ◽

High Prevalence ◽

Group B

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Analysis of virulence factors and antibiotic resistance genes in Group B Streptococcus from clinical samples

10.21203/rs.2.21004/v2 ◽

2020 ◽

Author(s):

Raymond Mudzana ◽

Rooyen T Mavenyengwa ◽

Muchaneta Gudza-Mugabe

Keyword(s):

Antibiotic Resistance ◽

Pregnant Women ◽

Virulence Factors ◽

Resistance Genes ◽

Virulence Genes ◽

Group B Streptococcus ◽

Antibiotic Resistance Genes ◽

Virulence Gene ◽

Clinical Samples ◽

Group B

Abstract Background : Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. GBS virulence factors are important in vaccine development, whilst antibiotic resistance genes are necessary in understanding the resistance mechanisms used by pathogens. This study was carried out to identify virulence genes and antibiotic resistance genes associated with GBS isolated from pregnant women. Methods: A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods including molecular tests. Antibiotic susceptibility testing using 3 antibiotics was done using the modified Kirby-Bauer method. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0 and the Spearman rank correlation test used to determine correlation among genes. Results: Nine distinct virulence gene profiles were identified. The profiles hly-scpB-bca-rib 37.2% (16/43) and hly-scpB-bca 18.6% (8/43) were common. The following virulence gene frequencies were obtained namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by clindamycin 55.8% (24/43) and erythromycin 30.2% (13/43). Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43). Conclusion: The study showed high prevalence of multiple virulence genes hly, scpB, bca and rib in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was found to be predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.

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Uncertainties in Screening and Prevention of Group B Streptococcus Disease

Clinical Infectious Diseases ◽

10.1093/cid/ciy1069 ◽

2018 ◽

Vol 69 (4) ◽

pp. 720-725 ◽

Cited By ~ 2

Author(s):

Kirsty Le Doare ◽

Paul T Heath ◽

Jane Plumb ◽

Natalie A Owen ◽

Peter Brocklehurst ◽

...

Keyword(s):

Pregnant Women ◽

Point Of Care ◽

Group B Streptococcus ◽

Research Priorities ◽

Term Infant ◽

Department Of Health ◽

Health And Social Care ◽

Intrapartum Antibiotic ◽

Group B ◽

The Impact

Abstract In autumn 2016, the UK Department of Health (now Department of Health and Social Care) convened 2 meetings to discuss how to address research evidence gaps in order to minimize the impact of infant group B streptococcus (GBS) disease in the United Kingdom. At that meeting, a number of research priorities were highlighted, including improving the screening for GBS colonization in pregnant women, offering intrapartum antibiotic prophylaxis and point-of-care testing, and understanding the effect of widespread intrapartum antibiotic use on long-term infant health. Further discussions involved investigating the feasibility of a large prospective study of pregnant women and their infants in order to understand the role of antibodies in the protection against GBS disease in infancy following maternal exposure to GBS colonization. Here, we summarize the research uncertainties identified at that meeting.

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