Early-onset Group B Streptococcus Research Articles

Rapid intrapartum test for maternal group B streptococcal colonisation and its effect on antibiotic use in labouring women with risk factors for early-onset neonatal infection (GBS2): cluster randomised trial with nested test accuracy study

BackgroundMother-to-baby transmission of group B Streptococcus (GBS) is the main cause of early-onset infection. We evaluated whether, in women with clinical risk factors for early neonatal infection, the use of point-of-care rapid intrapartum test to detect maternal GBS colonisation reduces maternal antibiotic exposure compared with usual care, where antibiotics are administered due to those risk factors. We assessed the accuracy of the rapid test in diagnosing maternal GBS colonisation, against the reference standard of selective enrichment culture.MethodsWe undertook a parallel-group cluster randomised trial, with nested test accuracy study and microbiological sub-study. UK maternity units were randomised to a strategy of rapid test (GeneXpert GBS system, Cepheid) or usual care. Within units assigned to rapid testing, vaginal-rectal swabs were taken from women with risk factors for vertical GBS transmission in established term labour. The trial primary outcome was the proportion of women receiving intrapartum antibiotics to prevent neonatal early-onset GBS infection. The accuracy of the rapid test was compared against the standard of selective enrichment culture in diagnosing maternal GBS colonisation. Antibiotic resistance profiles were determined in paired maternal and infant samples.ResultsTwenty-two maternity units were randomised and 20 were recruited. A total of 722 mothers (749 babies) participated in rapid test units; 906 mothers (951 babies) were in usual care units. There was no evidence of a difference in the rates of intrapartum antibiotic prophylaxis (relative risk 1.16, 95% CI 0.83 to 1.64) between the rapid test (41%, 297/716) and usual care (36%, 328/906) units. No serious adverse events were reported. The sensitivity and specificity measures of the rapid test were 86% (95% CI 81 to 91%) and 89% (95% CI 85 to 92%), respectively. Babies born to mothers who carried antibiotic-resistant Escherichia coli were more likely to be colonised with antibiotic-resistant strains than those born to mothers with antibiotic-susceptible E. coli.ConclusionThe use of intrapartum rapid test to diagnose maternal GBS colonisation did not reduce the rates of antibiotics administered for preventing neonatal early-onset GBS infection than usual care, although with considerable uncertainty. The accuracy of the rapid test is within acceptable limits.Trial registrationISRCTN74746075. Prospectively registered on 16 April 2015

Análise da Prevalência e Conduta das Gestantes Colonizadas por Estreptococo do Grupo B e Evolução de seus Recém-Nascidos segundo o guideline de 2010 do Centers for Disease Control and Prevention (CDC)

OBJECTIVE: To evaluate the implementation of the 2010 Centers for Disease Control and Prevention (CDC) guidelines by the obstetrics and neonatology teams of a tertiary public hospital located in Rio de Janeiro, Brazil. METHODS: This retrospective study included the medical records of pregnant women who underwent vaginal-rectal swabs at the hospital between Nov. 1, 2014 and Oct. 31, 2015. Of the 595 included swabs, 122 were positive for Group B Streptococcus (GBS). After excluding incomplete medical records, malformations, and women who delivered at other hospitals, 85 pregnant women with positive swabs and 92 newborns were included. RESULTS: The prevalence of maternal colonization was 20.5%. The time to vaginal/rectal swab collection ranged from 18 to 39 weeks of gestation, with a mean of 34.9 weeks. Thirty-three of the 85 included pregnant women (38.9%) were not properly managed, since in 19 cases delivery occurred within less than four hours of antibiotic administration, and in 14 prophylaxis was not initiated when indicated. Five of the 92 included newborns (5.4%) were not properly managed, mainly due to unnecessary screening for infection; screening was incomplete in one case, since blood culture was not ordered although the guidelines in effect required it. Of the 86 newborns with management considered adequate, 53 (61.6%) had mothers who were also adequately managed. Thirty-three (57.75%) of the newborns managed adequately had mothers submitted to inadequate obstetric management. CONCLUSIONS: Although the 2010 CDC guidelines for prevention of early sepsis by GBS has been implemented in the hospital, we have detected failures in maternal intrapartum prophylaxis and newborn assessment. Failure to adhere to the established guidelines yields missed opportunities to prevent early-onset GBS sepsis.

Duration of intrapartum ampicillin prophylaxis and neonatal outcomes

At least 4 hours (hrs) of intrapartum ampicillin (amp) is recommended in patients colonized by Group B Streptococcus (GBS) to prevent early-onset GBS sepsis. However, shorter durations are known to have some protective effect. We compared neonatal outcomes based on the duration of intrapartum amp prophylaxis in the current era of neonatal care in a single center.

Evaluation of the Revogene® GBS DS assay performance for the intrapartum screening of group B streptococcus in comparison with intrapartum culture

Prevention of perinatal Group B Streptococcus (GBS) transmission is crucial in our effort to prevent Early-onset GBS disease. Here, we established the performance of the Revogene GBS DS assay for the detection of group B streptococcus on intrapartum vaginal samples in a laboratory environment using a prospective noninterventional study design. Intrapartum vaginal swabs were enriched using a selective culture method which served as study reference method. Overall, 119 patients were enrolled with an antenatal and intrapartum Group B Streptococcus colonization prevalence of 12.9% and 11.8%, respectively. Compared to intrapartum culture, the Revogene GBS DS assay had a sensitivity of 92.9% and a specificity of 99.1%, while the antenatal culture displayed a sensitivity 78.6% of and specificity of 96.2%. The Revogene GBS DS assay displayed an acceptable performance according to the European Group B Streptococcus consensus recommendations. Complementary studies in clinical practice are needed to confirm these findings.

Parents experiences of having an infant with early onset group B streptococcus infection.

The study explores parents lived experience of having an infant with early onset group B streptococcus (GBS). The study adopts a qualitative approach and a phenomenological framework with written autobiographical accounts as the method of data collection. Twenty-seven parents wrote first-hand accounts of their experience of having an infant with early onset GBS. Participants documented their experiences in their own way, reporting their thoughts and feelings, experiences, and events that were meaningful to them. Four themes were developed from data analysis: 'bonding'; 'grief'; 'communication and information provision'; and 'future family'. The study findings demonstrate the complexity of emotions within parent's experiences and highlight grief and loss as a core component of these experiences. Medical intervention, while acknowledged as being vital and in many cases lifesaving, was viewed as a disruption to early bonding experiences resulting in sadness and guilt. Variation in information provision, communication about this infection, and feeling that their infant's illness and/or death were preventable added to the sense of loss. Breakdowns in interpersonal communications with partners and family were commonly described and experiences of early onset GBS had implications for decision-making around future pregnancies.

The serotype distribution of Streptococcus agalactiae (GBS) carriage isolates among pregnant women having risk factors for early-onset GBS disease: a comparative study with GBS causing invasive infections during the same period in Denmark

BackgroundWe describe the serotype distribution of Streptococcus agalactiae (GBS) carriage isolates from women in labor and among GBS isolates causing invasive infections during the same period to see if the distribution of carriage serotypes reflects the GBS serotypes causing invasive diseases including early-onset disease (EOGBS).MethodsData on invasive isolates from 2019 including serotype, erythromycin and clindamycin susceptibility was retrieved from the Danish national reference laboratory, Statens Serum Institut. Carriage isolates were collected from women with risk factors for EOGBS enrolled at delivery at the maternity ward at a Danish University Hospital, first half of 2019.ResultsAmong carriage isolates, the dominant serotype was IX (21 %) followed by serotype III (19 %). The resistance to erythromycin and clindamycin was 21 and 26 %, respectively. Among invasive GBS isolates, no case of EOGBS with serotype IX was detected but the distribution of serotypes were otherwise similar to the GBS carrier strains. The corresponding resistance to erythromycin and clindamycin was 23 and 15 %, respectively. Penicillin resistance was not detected among carriage nor invasive isolates.ConclusionsThe distribution of serotypes among carriage and invasive GBS reflects the assumption that EOGBS occur following transmission of GBS from mother to newborn, with the exception of serotype IX.

Clinical Profile and Outcome of Group B Streptococcal Colonization in Mothers and Neonates in Ras Al Khaimah, United Arab Emirates: A Prospective Observational Study.

Background:Maternal Group B Streptococcus (GBS)/Streptococcus agalactiae colonization rates vary worldwide; however, no such recent data are available from the United Arab Emirates (UAE).Objective:The objective of this study was to determine the prevalence of GBS colonization among pregnant women attending an antenatal clinic of a hospital in Ras Al Khaimah, UAE, along with the antibiotic sensitivity pattern, the clinical profile and pregnancy (maternal and fetal) outcome.Methods:This prospective observational study routinely offered rectovaginal swab for GBS to all women attending the antenatal clinic at 35–37 weeks of pregnancy between January and December 2019. MASTASTREP kit and Vitek-2 identification system was used for culture and identification. Women with positive cultures were followed up for any maternal and neonatal complications and the use of intrapartum antibiotic prophylaxis (IAP).Results:A total of 2295 women were included, of which 158 (6.9%) had positive cultures for GBS colonization. The carriage rate was higher in women without any risk factors for early-onset GBS disease (EOGBS) (P < 0.01). The GBS isolates were about 97% susceptible to linezolid and vancomycin, 90% to benzyl penicillin and 95% to ampicillin. Resistance to trimethoprim/sulfamethoxazole, clindamycin, erythromycin, and levofloxacin were about 77%, 57%, 57%, and 10%, respectively. Urinary tract infection in GBS colonized women were more common in those aged ≤30 years (P = 0.009). Fetal outcome was favorable in women receiving IAP for GBS colonization. No neonate had culture proven EOGBS.Conclusion:The prevalence of GBS colonization in pregnant women as well as the overall maternal and neonatal complications is low in Ras Al Khaimah, UAE. IAP is effective in preventing early-onset sepsis in newborn, and thus should be initiated in those with GBS colonization. The cultured GBS showed sensitivity to most antibiotics.

Outcomes in reported penicillin allergic mothers and neonates requiring Group B streptococcal prophylaxis: a retrospective observational cohort study

BackgroundInfectious morbidity and mortality in the first week of life is commonly caused by early-onset neonatal Group B streptococcus (GBS) disease. This infection is spread from GBS positive mothers to neonates by vertical transmission during delivery and results in serious illness for newborns. Intrapartum prophylactic antibiotics have decreased the incidence of early-onset neonatal GBS disease by 80%. Patients labeled with a penicillin allergy (PcnA) alternatively receive either vancomycin or clindamycin but effectiveness is controversial. We evaluated the influence of a reported PcnA label versus no PcnA label on inpatient maternal and neonatal outcomes.MethodsOur goal was to examine the relationship between a PcnA label, maternal and neonatal outcomes, and hospital costs. We collected retrospective data with institutional IRB approval from 2016 – 2018 for hospitalized patients who were GBS positive, pregnant at time of admission, ≥ 18 years of age, received antibiotic prophylaxis for GBS, were labeled as PcnA or non-PcnA, and completed a vaginal delivery. Patient characteristics and maternal/neonatal outcomes were examined. Statistical tests included calculations of means, medians, proportions, Mann–Whitney, two-sample t-tests, Chi-squared or Fisher’s Exact tests, and generalized linear and logistic regression models. Significance was set at p < 0.05.ResultsMost PcnA patients were white, older, had a higher median body mass index and mean heart rate, and a greater proportion used tobacco than non-PcnA patients. In regression analyses, PcnA hospitalized patients received a shorter duration of antibiotic treatment than non-PcnA patients [incidence rate ratio (IRR): 0.45, 95% CI: 0.38–0.53]. PcnA patients were also more likely to have their baby’s hospital LOS be > 48 h [adjusted odds ratio (AOR): 1.35, 95% CI: 1.07–1.69] even though the PcnA mothers’ LOS was not different from non-PcnA mothers. Cost of care, mortality, intensive care, median parity, mean gravidity, and miscarriage were similar between the groups.ConclusionsIn hospitalized obstetric patients, a PcnA label was associated with a shorter maternal course of antibiotic treatment and a longer neonatal LOS. Further prospective studies are needed to clarify the underlying reasons for these outcomes.

Epidemiology and Trends of Infective Meningitis in Neonates and Infants Less than 3 Months Old in Hong Kong

ObjectivesMeningitis in neonates and young infants leads to significant morbidity and mortality worldwide. This study aimed to investigate pathogens, antibiotic resistance and secular change of incidence in Hong Kong. MethodsA retrospective search was performed on meningitis in neonates and infants aged <3 months in three Hong Kong public hospitals from 2004 to 2019. Medical charts were reviewed, with focus on the identification and antibiotic resistance of the pathogens. ResultsA total of 200 cases of meningitis were identified (67% were bacterial). Group B Streptococcus (GBS) and Escherichia coli (E. coli) were the commonest bacterial pathogens. The annual rates of early-onset GBS meningitis decreased after the implementation of universal GBS screening and intrapartum antibiotic prophylaxis (IAP) in 2012, while that of late-onset GBS meningitis remained similar. A significant portion of E. coli isolates were resistant to ampicillin and/or gentamicin. ConclusionGBS and E. coli were the most common bacteria for meningitis in this age group. The annual rate of bacterial meningitis in Hong Kong has declined in recent years, which has been attributed to the decline in early-onset GBS meningitis due to universal GBS screening and IAP. Antimicrobial-resistant bacterial strains that cause meningitis require further clinical and public health attention.

Current status of group B Streptococcus infection in neonates: a multicenter prospective study.

To investigate the incidence of maternal group B Streptococcus (GBS) colonization and neonatal early-onset GBS disease (GBS-EOD), and to study the factors associated with the development of GBS-EOD in the offspring of pregnant women with GBS colonization. A total of 16 384 pregnant women and 16 634 neonates delivered by them were enrolled prospectively who had medical records in Xiamen Maternal and Child Care Hospital, Beijing Obstetrics and Gynecology Hospital of Capital Medical University, and Zhangzhou Zhengxing Hospital from May 1, 2019 to April 30, 2020. Unified GBS screening time, culture method, and indication for intrapartum antibiotic prophylaxis (IAP) were adopted in the three hospitals. The incidence rates of maternal GBS colonization and neonatal GBS-EOD were investigated. A multivariate logistic regression analysis was used to identify the factors associated with the development of GBS-EOD in the offspring of pregnant women with GBS colonization. In these three hospitals, the positive rate of GBS culture among the pregnant women in late pregnancy was 11.29% (1 850/16 384), and the incidence rate of neonatal GBS-EOD was 0.96‰ (16/16 634). The admission rate of live infants born to the GBS-positive pregnant women was higher than that of those born to the GBS-negative ones (P<0.05). The live infants born to the GBS-positive pregnant women had a higher incidence rate of GBS-EOD than those born to the GBS-negative ones [6.38‰ (12/1 881) vs 0.27‰ (4/14 725), P<0.05]. The multivariate logistic regression analysis showed that placental swabs positive for GBS and positive GBS in neonatal gastric juice at birth were independent predictive factors for the development of GBS-EOD (P<0.05), while adequate IAP was a protective factor (P<0.05) in the offspring of pregnant women with GBS colonization. GBS colonization of pregnant women in late pregnancy has adverse effects on their offspring. It is important to determine prenatal GBS colonization status of pregnant women and administer with adequate IAP based on the indications of IAP to reduce the incidence of neonatal GBS-EOD. Citation.

Preventing early-onset group B streptococcal sepsis: clinical risk factor-based screening or culture-based screening?

Two strategies are available for prevention of early-onset group B streptococcal (GBS) sepsis - clinical risk factor-based screening and routine culture-based screening of pregnant women for GBS colonisation. In our hospital, we switched from the former to the latter approach in 2014. We compared the incidence of early-onset GBS sepsis during 2001-2015 between infants born to pregnant women who were screened for GBS colonisation and those born to women who were not screened. Among 41,143 live births, there were nine cases of early-onset GBS sepsis. All infants with GBS sepsis were born to pregnant women who were not screened for GBS colonisation. The incidence of early-onset GBS sepsis among infants of women who were not screened was 0.41 per 1,000 live births (95% confidence interval [CI] 0.19-0.77) when compared to infants of women who were screened, for whom the sepsis incidence was zero per 1,000 live births (95% CI 0-0.19; p = 0.005). Our data suggests that routine culture-based screening of pregnant women for GBS colonisation is a better preventive strategy for early-onset GBS sepsis in neonates when compared to clinical risk factor-based screening.

Rapid Intrapartum Test for Maternal Group B Streptococcal Colonisation and its Effect on Antibiotic Use in Labouring Women with Risk Factors for Early Onset Neonatal Infection (GBS2): Cluster Randomised Trial with Nested Test Accuracy Study

Background: We evaluated whether use of point-of-care rapid intrapartum test to detect maternal GBS colonisation reduces maternal antibiotics exposure compared with usual care, where antibiotics are administered due to clinical risk factors. We assessed the accuracy of the rapid test in diagnosing maternal GBS colonisation, against the reference standard of selective enrichment culture. Methods: Parallel-group cluster randomised trial with nested test accuracy study and microbiological sub-study in 20 maternity units in UK randomised to a strategy of rapid test (GeneXpert GBS system, Cepheid) or usual care. The main outcomes were maternal intrapartum antibiotics administered to prevent neonatal early-onset GBS infection, accuracy of the rapid test, and antibiotic resistance profiles in maternal and infant samples. The trial was registered ISRCTN74746075 Findings: 722 mothers (749 babies) participated in rapid test units; 906 mothers (951 babies) in usual care units. There was no evidence of a difference in the primary outcome (Risk ratio 1.16, 95% CI 0.83 to 1.64) between the rapid test (41%, 297/716) and usual care (36%, 328/906) units. The sensitivity and specificity measures of the rapid test were 86% (95% CI 81 to 91%) and 89% (95% CI 85 to 92%) respectively. Interpretation: Use of intrapartum rapid test to diagnose maternal GBS colonisation did not reduce the rates of antibiotics administered for preventing neonatal early-onset GBS infection than usual care, although with considerable uncertainty. The accuracy of the rapid test is within acceptable limits. Trial Registration: ISRCTN74746075 Funding: National Institute for Health Research Health Technology Assessment programme (13/82/04). Declaration of Interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf. JP is the Chief Executive of Group B Strep Support, a Charity working to stop GBS in babies. JP received support from Cepheid to attend an academic conference in 2016, from Pfizer to attend a summit for vaccine advocacy stakeholders in the USA in 2019 and from i-CONSENT to attend workshops in London in 2018 and Brussels in 2019 regarding consent for vaccine trials. JP was a member of the Department of Health research prioritisation expert group in 2016. JP and JG are members of the NICE guideline update committee for Neonatal infection: antibiotics for prevention and treatment (update). JG was a member of the NICE Diagnostics Advisory Committee that produced DG38 Rapid tests for group A streptococcal infections in people with a sore throat (which included assessment of the Cepheid GeneXpert Xpert® Xpress Strep A test) (Published November 2019). JPD, JP, JG are grant holders for HTA 17/86/06 (GBS3), a cluster randomised trial of routine screening for GBS. JPD and JP are grant applicants for a study to determine a serocorrelate of immune protection against GBS. All other authors declare no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work. JJD is supported by the NIHR Birmingham Biomedical Research Centre at the University Hospitals Birmingham NHS Foundation Trust and the University of Birmingham. Ethics Approval Statement: This study was approved by the West Midlands – Edgbaston Multi centre Research Ethics Committee (16/WM/0036), including waiver of individual research consent.

Hypervirulent Streptococcus agalactiae septicemia in twin ex-premature infants transmitted by breast milk: report of source detection and isolate characterization using commonly available molecular diagnostic methods

BackgroundGroup B Streptococcus (GBS) infections caused by Streptococcus agalactiae is a leading cause of meningitis and sepsis in neonates, with early-onset GBS symptoms emerging during the first week of life and late-onset occurring thereafter. Perinatal transmission of GBS to the neonate through the birth canal is the main factor associated with early-onset neonate infections, while less is understood about the source of late-onset infections.MethodsIn this report we describe a case of twin ex-premature infants who presented one month after birth with GBS septicemia. The mother had been appropriately screened at gestational age 35–37 weeks and laboratory methods failed to detect GBS colonization by culture or clinical molecular methods. In attempts to identify and isolate the source of GBS infection, additional surveillance swabs were collected from the mother at the time of neonate admission. Culture and a commercially available, FDA-cleared molecular PCR assay were performed.ResultsNo GBS was detected from swabs collected from the perianal, thigh/groin or axillary areas. However, expressed breast milk and swabs from the breastmilk pump were positive by both methods. Since simultaneous culture and molecular methods which used breastmilk as a source were performed, investigators ascertained the limit of detection for GBS in breastmilk. The limit of detection was determined to be tenfold lower than that of LIM-broth enriched cultures—the FDA-approved source. Subsequent whole genome sequencing (WGS) analysis of isolates recovered from breastmilk and blood cultures from the infants demonstrated all strains were related and characterized as ST-452. Both infants responded very well to treatment and continued to have no related events or concerns at the two-year follow up appointment.ConclusionsStrain type 452 (capsular type IV) has recently emerged as a hypervirulent strain and has previously been documented as causing GBS infections in elderly populations. Antibiotic therapy resolved both mother and infant infections. Subsequent testing for the presence of GBS in breastmilk samples also showed an absence of bacteria. This is the first report of infant twins late-onset GBS infections caused by the hypervirulent S. agalactiae ST-452 with breastmilk as the source.

子宮内での敗血症発症が示唆された早発型B群溶血性連鎖球菌（GBS）感染症による新生児死亡の一例

子宮内での敗血症発症が示唆された早発型B群溶血性連鎖球菌（GBS）感染症による新生児死亡の一例

Improvement of selection of pregnant women for intrapartum polymerase chain reaction screening for vaginal Group B Streptococci (GBS) colonization by adding GBS urine screening at 35-37 weeks of pregnancy.

To evaluate whether systematic antepartum screening for Group B Streptococci (GBS) by urine culture improves the risk factor-based selection of pregnant women for intrapartum GBS screening with a rapid polymerase chain reaction (PCR) assay. A prospective observational study was conducted between April 2013 and June 2014. GBS colonization judged by urine culture at 35-37weeks of gestation was compared with the result of a vaginal GBS PCR test at labor as outcome. The results of urine culture were used as exposure variable. The PCR test was performed on intrapartum vaginal samples. Screening for urine GBS in 902 unselected pregnant Danish women at 35-37weeks of gestation predicted intrapartum PCR GBS status with a sensitivity of 33.6%. A positive predictive value of 41.2% was seen among women with low GBS counts (<104CFU/mL) and 83.3% among women with high GBS counts (≥104CFU/mL). Systematic GBS screening of urine at 35-37weeks of gestation added 30.9% extra women for intrapartum GBS PCR screening in the study group. Systematic antepartum GBS screening of urine should be implemented in order to improve risk stratification for early onset GBS by offering laboring women an intrapartum GBS PCR test.

A comparison of GenomEra\xae GBS PCR and GeneXpert \xae GBS PCR assays with culture of GBS performed with and without broth pre-enrichment

This study was designed to compare the performance of GeneXpert® and GenomEra® group B streptococcus (GBS) PCR assays, held up against standard culture of GBS performed with and without broth pre-enrichment. In Denmark, the strategy for preventing early onset GBS infection (EOGBS) is risk factor based. Three hundred and sixty six women fulfilling one or more of the criteria for presence of risk factors for EOGBS were prospectively included. Rectovaginal swab samples were taken intrapartum and tested bed-site by the GenomEra® and the GeneXpert® GBS PCR assays and cultured at the microbiology laboratory using Granada agar plates with and without prior growth of sampling material in selective enrichment broth. Among 366 participants tested intrapartum, 99 were GBS-positive by culture, 95 by GenomEra, and 95 by GeneXpert. Compared with culture, the GenomEra and the GeneXpert performed with a sensitivity of 91.8% and 91.7% and a specificity of 98.1% and 97.3%, respectively. A combined reference standard was established by defining true positives as either culture-positive samples or culture-negative samples where both the GeneXpert and the GenomEra GBS PCR assays were positive. Using this, the sensitivity increased to 92.2% and the specificity to 99.6% for GenomEra and to 92.0% and 96.8% for GeneXpert. The use of selective broth enrichment found only three additional GBS culture-positive samples. The performance of the two PCR methods examined was very similar and close to the findings by culture, and both PCR assays are thus applicable as rapid intrapartum bed-site tests.

Identification of Group B Streptococcus Serotypes and Genotypes in Late Pregnant Women and Neonates That Are Associated With Neonatal Early-Onset Infection in a South China Population.

Background: Group B streptococcus (GBS) colonized in late pregnancies has been associated with neonatal early-onset GBS disease (GBS-EOD) in China.Objective: This study investigated if GBS serotype and genotype in late pregnancy is associated with GBS-EOD, providing a reference for GBS-EOD prevention and treatment.Methods: A total of 298 pregnant women with GBS colonization during their late pregnancy and 32 invasive GBS-EOD cases were included in this study for GBS serotyping and genotyping using commercial kits and DNA sequencing.Results: We identified 266 GBS strains from mothers whose newborns were not infected with GBS-EOD. Serotype III [54.9% (146/266)] was the most common serotype, followed by Ib [17.3% (46/266)] and V [10.1% (27/266)]. ST19 was the most prevalent genotype [19.9% (53/266)], followed by ST862 [9.4% (25/266)] and ST12 [7.9% (21/266)]. We found that 32 mothers and their neonates with GBS-EOD had the same GBS strains. In 32 cases of GBS-EOD, the top three serotypes were III, Ia, and Ib, while the top three genotypes were ST17, ST23, and ST19. ST17 was the dominant genotype of serotype III, which was the most common prevalent in GBS-EOD [72.2% (13/18)], and ST23 was the dominant genotype of serotype Ia, the second most prevalent in GBS-EOD [87.5% (6/8)]. There were statistically significant differences in serotypes (p = 0.046) and genotypes (p = 0.000) distribution between the 266 pregnant women without GBS-EOD neonates and 32 cases of GBS-EOD.Conclusion: This study revealed a statistically significant associations of GBS serotype Ia, and ST17 and ST23 between GBS colonization in women during late pregnancy and in neonatal GBS-EOD. The GBS ST23 of serotype Ia and ST17 of serotype III possessed a strong pathogenicity.

Resistome and virulome study on pathogenic Streptococcus agalactiae Guangzhou-SAG036

Streptococcus agalactiae is considered as a leading case of bacterial infection among neonates. Although relative protection strategies have been performed in many high-income countries, resulting in a massive reduction in the occurrences of early-onset GBS disease, the late-onset disease has not affected. Here, the whole genome of S. agalactiae Guangzhou-SAG036 was sequenced by the Pacific Biosciences Sequel using the P4–C2 chemistry and the continuous long reads were used for de novo assembly using HGAP. Besides, genes prediction and multiply annotation were performed by comparing it with diverse databases. The whole genome has a length of 2,206,504 bp and contains 2162 predicted genes with an average G + C content of 35.85%. Based on the whole genome sequence, 2 large prophages, 20 virulence factors genes, and 8 antibiotic resistant genes were identified. MLST analysis revealed S. agalactiae Guangzhou-SAG036 was identified as ST-17. The virulence factors genes were identified with different functions including adherence, antiphagocytosis, spreading factor, immune evasion, invasion, toxin. Besides, the antibiotic-resistant genes may provide S. agalactiae with resistance to multi-drugs including erythromycin, streptomycin, azithromycin, spiramycin, ampicillin, kanamycin, cationic peptides, and tetracycline. Therefore, the infection of S. agalactiae Guangzhou-SAG036 ST-17 strain maybe caused by the complex virulence factors and multi-drugs resistance. These results contribute to further understand GBS epidemiology and surveillance targets.

The Role for Intra-Partum Antibiotics in Previously GBS-Colonised Pregnancies, Not So Straightforward After All: A Case Study

Background: Group B Streptococcus (GBS) is the most frequent pathogen involved in early-onset infection in newborn infants. The incidence of early-onset GBS disease (EOGBS) is estimated at 0.4 and 0.57 per 1000 births in the United States of America and the United Kingdom respectively. It is clear that administration of intrapartum antibiotics (IAP) significantly reduces risk of EOGBS (RR 0.17, 95% CI 0.04 to 0.74; number needed to treat to benefit 25, 95% CI 14 to 100), hence institutes such as the Royal College of Obstetrics and Gynecology (RCOG), and American College of Obstetrics and Gynecology (ACOG), have released clinical practice guidelines (CPGs) with the aim to improve the standard of care in GBS screening and IAP for the prevention of EOGBS in neonates. CPGs guide clinicians in their management based on a consensus of care drawn from clinical evidence and offer a standard of care for them to fall back on to guard against medical malpractice litigation. However, deviation from the intended clinical context or the failure to recognize the limits of such guidelines could compromise patient safety. Aim: The aim of this case study is to highlight the role and limitations of clinical practice guidelines in medical practice, through a case of an early onset GBS infection in a neonate that was a result of selectively applying the RCOG and ACOG guidelines outside their intended context. Conclusion: The case illustrates the importance of applying guidelines correctly within the appropriate clinical context but serves also as a reminder for clinicians to understand the limitations of them when accounting for other co-conditions patients often present with in daily medical practice.

Preventing Early-Onset Group B Streptococcus neonatal infection and reducing antibiotic exposure using a rapid PCR test in term prelabour rupture of membranes.

How best to target intrapartum antibiotic prophylaxis (IAP) to minimise both Early-Onset Group B Streptococcus (EOGBS) neonatal infection and maternal/fetal antibiotic exposure is uncertain, with both routine-screening and risk-factor approaches available. This retrospective cohort study was undertaken to examine the outcomes of a hybrid risk-and-screen approach to EOGBS prevention using GBS polymerase chain reaction (PCR). The target population was women with term prelabour rupture of membranes (TermPROM) having the risk factor of prolonged rupture of membranes (ROM) ≥18h. Non-labouring TermPROM women had rapid GBS PCR testing at presentation. GBS screen-positive women proceeded to induction of labour and received IAP. GBS screen-negative women were allowed home to await spontaneous labour and not given IAP regardless of duration of ROM, unless other risk factors developed. For all other women, the risk-factor approach was followed. From 2009 to 2018, there were 20 cases of culture-positive EOGBS, a rate of 0.36/1000 live births (95% CI 0.22-0.56/1000), comparable to other recent reports. Over 2010-2018 when laboratory data were available, 1120 TermPROM women with ROM ≥18h avoided antibiotics because they were GBS PCR-negative (2.3% of all births, 3.6% of vaginal births) while 338 TermPROM women with ROM <18h received targeted antibiotics for being GBS-positive. No cases of EOGBS occurred in TermPROM women, those with ROM ≥18h, or due to protocol-compliance failure. A hybrid approach involving risk-factor-based IAP and intrapartum GBS PCR screening of non-labouring TermPROM women delivers acceptably low rates of EOGBS while minimising and better targeting antibiotic exposure.