Group B streptococcal screening, intrapartum antibiotic prophylaxis, and neonatal early-onset infection rates in an Australian local health district: 2006-2016

Unraveling the Microbiome-Human Body Axis: A Comprehensive Examination of Therapeutic Strategies, Interactions and Implications

This review scrutinizes the intricate interplay between the microbiome and the human body, exploring its multifaceted dimensions and far-reaching implications. The human microbiome, comprising diverse microbial communities inhabiting various anatomical niches, is increasingly recognized as a critical determinant of human health and disease. Through an extensive examination of current research, this review elucidates the dynamic interactions between the microbiome and host physiology across multiple organ systems. Key topics include the establishment and maintenance of microbiota diversity, the influence of host factors on microbial composition, and the bidirectional communication pathways between microbiota and host cells. Furthermore, we delve into the functional implications of microbiome dysbiosis in disease states, emphasizing its role in shaping immune responses, metabolic processes, and neurological functions. Additionally, this review discusses emerging therapeutic strategies aimed at modulating the microbiome to restore host-microbe homeostasis and promote health. Microbiota fecal transplantation represents a groundbreaking therapeutic approach in the management of dysbiosis-related diseases, offering a promising avenue for restoring microbial balance within the gut ecosystem. This innovative therapy involves the transfer of fecal microbiota from a healthy donor to an individual suffering from dysbiosis, aiming to replenish beneficial microbial populations and mitigate pathological imbalances. By synthesizing findings from diverse fields, this review offers valuable insights into the complex relationship between the microbiome and the human body, highlighting avenues for future research and clinical interventions.

Characterization of invasive Group B Streptococcus isolates from Western Australian infants, 2004-2020

Background. Invasive Group B Streptococcus (GBS; Streptococcus agalactiae) remains a leading cause of infant morbidity and mortality. Intrapartum antibiotic prophylaxis (IAP) has been implemented in many countries with a reduction in early-onset disease, but an effective vaccine may further reduce the disease burden. Candidate vaccines targeting capsular polysaccharides and surface proteins are now in clinical trials.Methods. Using whole-genome sequencing and phenotypic antimicrobial susceptibility testing, we characterized sterile-site GBS isolates recovered from Western Australian infants between 2004 and 2020. Characteristics were compared between three time periods: 2004-2008, 2009-2015 and 2016-2020.Results. A total of 135 isolates were identified. The proportion of serotype III (22.7 % in Period 1 to 47.9 % in Period 3, P=0.04) and clonal complex 17 (13.6-39.6 %, P=0.01) isolates increased over time. Overall coverage of vaccines currently being trialled was >95 %. No isolates were penicillin resistant (MIC>0.25 mg l-1), but 21.5 % of isolates had reduced penicillin susceptibility (MIC>0.12 mg l-1) and penicillin MIC increased significantly over time (P=0.04). Clindamycin resistance increased over time to 45.8 % in the latest period.Conclusions. Based on comprehensive characterization of invasive infant GBS in Western Australia, we found that coverage for leading capsular polysaccharide and surface protein vaccine candidates was high. The demonstrated changes in serotype and molecular type highlight the need for ongoing surveillance, particularly with regard to future GBS vaccination programmes. The reduced susceptibility to IAP agents over time should inform changes to antibiotic guidelines.

Mood and microbes: a comprehensive review of intestinal microbiota's impact on depression

Depression is considered a multifaceted and intricate mental disorder of growing concern due to its significant impact on global health issues. The human gut microbiota, also known as the "second brain," has an important role in the CNS by regulating it through chemical, immunological, hormonal, and neurological processes. Various studies have found a significant bidirectional link between the brain and the gut, emphasizing the onset of depression therapies. The biological and molecular processes underlying depression and microbiota are required, as the bidirectional association may represent a novel study. However, profound insights into the stratification and diversity of the gut microbiota are still uncommon. This article investigates the emerging evidence of a bacterial relationship between the gut and the brain's neurological system and its potential pathogenicity and relevance. The interplay of microbiota, immune system, nervous system neurotransmitter synthesis, and neuroplasticity transitions is also widely studied. The consequences of stress, dietary fibers, probiotics, prebiotics, and antibiotics on the GB axis are being studied. Multiple studies revealed the processes underlying this axis and led to the development of effective microbiota-based drugs for both prevention and treatment. Therefore, the results support the hypothesis that gut microbiota influences depression and provide a promising area of research for an improved knowledge of the etiology of the disease and future therapies.

Neonatal Group B Streptococcal Infection in Australia: A Case-control Study

BACKGROUND

To determine maternal and neonatal risk factors for, and incidence of, neonatal early-onset group B streptococcus (EOGBS) and late-onset (LOGBS) infection in South Australia (SA) and the Northern Territory (NT).

METHODS

A case-control study with 2:1 matched controls to cases. The study included tertiary hospitals in South Australia and the Northern Territory, Australia. Retrospective data were collected from a 16-year epoch (2000-2015).

RESULTS

Of a total of 188 clinically suspected or confirmed cases, 139 were confirmed, of which 56.1% (n = 78) were EOGBS and 43.9% (n = 61) were LOGBS. The incidence of clinically suspected and confirmed cases of EOGBS was 0.26/1000 live births in SA and 0.73/1000 live births in the NT, and the incidence of confirmed cases was 0.19/1000 for SA and 0.36/1000 for the NT. The incidence of clinically suspected or confirmed LOGBS was 0.18/1000 live births in SA and 0.16/1000 for the NT. The majority of infants with GBS presented with sepsis, pneumonia, or meningitis. Developmental delay was the most commonly recorded long-term complication at 1 year old. Risk factors for EOGBS included maternal GBS carriage, previous fetal death, identifying as Aboriginal and/or Torres Strait Islander, and maternal fever in labor/chorioamnionitis.

CONCLUSIONS

GBS remains a leading cause of neonatal morbidity and mortality. Adding previous fetal death to GBS screening guidelines would improve GBS prevention. The introduction of maternal GBS vaccination programs should be guided by country-specific disease epidemiology.

Early-onset sepsis in very preterm neonates in Australia and New Zealand, 2007-2018

OBJECTIVE

To evaluate the epidemiology and population trends of early-onset sepsis in very preterm neonates admitted to neonatal intensive care units (NICU) in Australia and New Zealand.

DESIGN

Retrospective observational cohort study using a dual-nation registry database.

SETTING

29 NICUs that have contributed to the Australian and New Zealand Neonatal Network.

PARTICIPANTS

Neonates born at <32 weeks' gestation born between 2007 and 2018 and then admitted to a NICU.

MAIN OUTCOME MEASURES

Microorganism profiles, incidence, mortality and morbidity.

RESULTS

Over the 12-year period, 614 early-onset sepsis cases from 43 178 very preterm admissions (14.2/1000 admissions) were identified. The trends of early-onset sepsis incidence remained stable, varying between 9.8 and 19.4/1000 admissions (linear trend, p=0.56). The leading causative organisms were Escherichia coli (E. coli) (33.7%) followed by group B Streptococcus (GBS) (16.1%). The incidence of E. coli increased between 2007 (3.2/1000 admissions) and 2018 (8.3/1000 admissions; p=0.02). Neonates with E. coli had higher odds of mortality compared with those with GBS (OR=2.8, 95% CI 1.2 to 6.1). Mortality due to GBS decreased over the same period (2007: 0.6/1000 admissions, 2018: 0.0/1000 admissions; p=0.01). Early-onset sepsis tripled the odds of mortality (OR=3.0, 95% CI 2.4 to 3.7) and halved the odds of survival without morbidity (OR=0.5, 95% CI 0.4 to 0.6).

CONCLUSION

Early-onset sepsis remains an important condition among very preterm populations. Furthermore, E. coli is a dominant microorganism of very preterm early-onset sepsis in Australia and New Zealand. Rates of E. coli have been increasing in recent years, while GBS-associated mortality has decreased.

Adherence to screening and management guidelines of maternal Group B Streptococcus colonization in pregnancy

Aims

To investigate Group B Streptococcus (GBS) colonization in pregnancy; adherence to antenatal GBS screening and adherence to the intrapartum antibiotics protocol within two models of care (midwifery and non‐midwifery led).

Design

This retrospective quantitative study has employed a descriptive design using administrative health data.

Methods

Data from five maternity hospitals in metropolitan and regional Western Australia that included 22,417 pregnant women who gave birth between 2015 and 2019 were examined, applying descriptive statistics using secondary data analysis.

Results

The study revealed an overall GBS colonization rate of 21.7% with similar rates in the different cohorts. A lower adherence to screening was found in the midwifery led model of care (MMC, 68.76%, n = 7232) when compared with the non‐midwifery led model of care (NMMC, 90.49%, n = 10,767). Over the 5 years, screening rates trended down in the MMC with stable numbers in the counterpart. Adherence in relation to intrapartum antibiotic prophylaxis revealed discrepant findings between the study groups.

Conclusion

Adherence to screening and management guidelines of maternal GBS colonization in pregnancy is lower within the MMC when compared with the NMMC.

Impact

This is the first cohort study to describe the adherence to the recommended Western Australian GBS screening guidelines in the two different models of care. Findings may assist in the guidance and improvement of clinical protocols as well as the planning of clinical care in relation to GBS screening to reduce the risk of neonatal GBS infection.

Impact of antibiotics on the human microbiome and consequences for host health

It is well established that the gut microbiota plays an important role in host health and is perturbed by several factors including antibiotics. Antibiotic-induced changes in microbial composition can have a negative impact on host health including reduced microbial diversity, changes in functional attributes of the microbiota, formation, and selection of antibiotic-resistant strains making hosts more susceptible to infection with pathogens such as Clostridioides difficile. Antibiotic resistance is a global crisis and the increased use of antibiotics over time warrants investigation into its effects on microbiota and health. In this review, we discuss the adverse effects of antibiotics on the gut microbiota and thus host health, and suggest alternative approaches to antibiotic use.

Intrapartum antibiotic prophylaxis for women who are screened positive for group B streptococcal colonisation: Clinical compliance with the guideline

BACKGROUND

In high income countries, ~30% of pregnant women are provided with intrapartum antibiotic prophylaxis (IAP) for early-onset group B streptococcal infection (EOGBSI). The infection rate is low, 0.2/1000 livebirths in our jurisdiction, and others. We hypothesised factors, other than IAP alone, were reasons for the low rate of EOGBSI.

AIMS

Compliance with our local guideline, referred to here as 'the guideline'.

METHOD

Compliance was defined as an initial dose of benzylpenicillin IAP followed by four-hourly doses until birth. The study population was drawn from 4098 women who had 4100 pregnancies resulting in 4200 babies in an Australian birth setting from 1/1/2016 to 31/12/2016. Most, 93%, were eligible for universal GBS screening, 67% were reported as screened and 90% of these had a result documented; 23% were positive for GBS. A random sample (n = 223) was taken for further analysis.

RESULTS

The adjusted odds of receiving benzylpenicillin IAP in accord with the guideline were three times higher among primiparous compared to multiparous women (P < 0.001, odds ratio (OR) = 3.4, 95% CI 1.7-6.7) and three times higher among women experiencing induction of labour compared to women who commenced labour spontaneously (P < 0.001, OR = 3.4, 95% CI 1.8-6.3). Of the 223 women, 188 received IAP: 176 received benzylpenicillin IAP, 31% (or 24% of the total sample) received this intervention in accord with the guideline, 24% received benzylpenicillin ≥4 h before birth but not in accord with the guideline and 44% received benzylpenicillin <4 h before birth.

CONCLUSION

We conclude that sub-optimal compliance was largely a consequence of an unrealistic guideline.

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

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.

Indications and Clinical Profile of Neonatal Admissions: A Cross-Sectional Descriptive Analysis from a Single Academic Center in Jordan

PURPOSE

To review the indications and clinical profile of neonatal admissions at King Abdullah University Hospital in Jordan.

MATERIALS AND METHODS

We conducted a cross-sectional review of all neonates admitted to the neonatal intensive care unit between September 2016 and September 2018. Collected data include demographic characteristics, indications for admission, morbidities and mortality, and discharge outcomes. Findings were reported among term and preterm infants.

RESULTS

A total of 1444 infants were admitted during the study period of whom 1332 (92.2%) were inborn and 612 (42.4%) were term neonates. Of the 832 preterm infants, 545 were late preterm (34-36 6/7 gestation) and 125 had very low birth weight (˂ 1500 grams); 925 (64%) were born by cesarean section. Respiratory failure of the newborn (41.2%) and prematurity (33.3%) were the main indications for admission among the whole cohort. Maternal prolonged premature rupture of membranes (PROM) was observed in nearly half the admissions of term infants. Hypoxic ischemic encephalopathy (3.2% vs 0.7%, p 0.01) and congenital anomalies (5% vs 1.2%, p 0.03) were more common in term infants. The rate of bronchopulmonary dysplasia was 39% among <28-week and 28% among <32-week premature infants. Sepsis was encountered in 59 infants. The overall mortality rate was 3.8%. Prematurity was the main predisposing factor for mortality (Adjusted OR: 9.9, 95% CI: 3.5, 27.6).

CONCLUSION

The majority of neonatal admissions at our institution are term and late preterm infants delivered by cesarean section. Prematurity, respiratory failure of the newborn, and suspected sepsis due to maternal PROM are the leading causes of admission. The mortality rate is within WHO target to achieve Sustainable Development Goal 3. Population-based studies are needed to make better conclusions that represent the whole Jordanian population. A revisit for the indications of cesarean deliveries may help to improve the neonatal outcomes.

Abuse of Antibiotics in Perinatology: Negative Impact for Health and the Economy

To use medications appropriately, patients need to be treated based on their clinical conditions, in doses that are based on their individual requirements, for an adequate amount of time, and at the lowest expense. The perinatal period is characterized by an excessive use of antibiotics. This antibiotic abuse can lead to antibiotic resistance, microbiome alterations, and dysbiosis, which have been associated with serious complications such as infections, abnormal brain development, allergies, autoimmune disorders, obesity, and an increase in mortality as well as an increase in health care expenditures. The need to optimize antibiotic utilization in perinatal medicine has never been more urgent; there is not much more time to wait.

A Cross-sectional Study of Group B Streptococcus-Associated Sepsis, Coinfections, and Antibiotic Susceptibility Profile in Neonates in Pakistan

BACKGROUND

Neonatal sepsis is a leading cause of morbidity and early-life mortality worldwide, and previous data have reported the highest neonatal mortality rate in Pakistan.

PURPOSE

The present study aimed to decipher the prevalence of group B Streptococcus (GBS)-associated sepsis, coinfections, and antibiotic susceptibility of isolated microbes in neonates.

METHODS

Blood samples of 100 cases of neonatal sepsis were subcultured on blood agar, GBS agar, and MacConkey agar for isolation of GBS and suspected microbes.

RESULTS

Of 100 neonatal blood samples, 85 blood samples were culture-positive, including mixed culture growth (n = 18), 25 samples as early-onset neonatal sepsis (EONS) and 60 as late-onset neonatal sepsis (LONS). Staphylococcus aureus showed high percent positivity (31.4%), followed by Candida sp (16.5%), GBS (14.1%), Klebsiella (14.1%), Staphylococcus epidermidis (11.8%), Pseudomonas (9.4%), Acinetobacter (9.4%), Esherichia coli (8.2%), and Enterococcus (5.9%). GBS was isolated more frequently from EONS than from LONS with 50% coinfections. Mode of delivery, gender, and respiratory distress in neonates were significantly associated with culture-positive sepsis. GBS isolates were highly (91.7%) susceptible to vancomycin, cefotaxime, and chloramphenicol, followed by penicillin (83.3%), ampicillin, and tetracycline (75%). GBS isolates were resistant to erythromycin, clindamycin, ciprofloxacin, and linezolid.

IMPLICATIONS FOR PRACTICE

Our findings evidenced GBS-associated risk factors and antibiotic susceptibility pattern of neonatal sepsis, which will help clinicians in management, control, and treatment of neonatal sepsis.

IMPLICATIONS FOR RESEARCH

The epidemiological evidence of GBS-associated neonatal sepsis, demographic characteristics, risk factor data analysis, and drug resistance pattern has disease prevention implications in neonates in low-income countries including Pakistan.

To screen or not to screen women for Group B Streptococcus (Streptococcus agalactiae) to prevent early onset sepsis in newborns: recent advances in the unresolved debate

Streptococcus agalactiae, also known as Group B streptococcus (GBS) is the commonest cause of early onset sepsis in newborns in developed high-income countries. Intrapartum antimicrobial (antibiotic) prophylaxis (IAP) is recognized to be highly effective in preventing early onset Group B sepsis (EOGBS) in newborns. The key controversy is about the strategy that should be used to identify mothers who should receive IAP. There are two strategies that are followed in developed countries: screening-based or risk-factor-based identification of women requiring IAP. The debate regarding which of the two approaches is better has intensified in the recent years with concerns about antimicrobial resistance, effect on newborn’s microbiome and other adverse effects. In this review, we have discussed some of the key research papers published in the period 2015–2019 that have addressed the relative merits and disadvantages of screening versus risk-factor-based identification of women requiring IAP. Although screening-based IAP appears to be more efficacious than risk-based IAP, IAP-based prevention has several limitations including ineffectiveness in prevention of late-onset GBS infection in babies, premature and still births, impact of IAP on neonatal microbiota, emergence of antimicrobial resistance and difficulties in implementing IAP-based strategies in middle and low income countries. Alternative strategies, principally maternal immunization against GBS would circumvent use of IAP. However, no licensed vaccines are currently available for use.

Neonatal sepsis in low-income countries: epidemiology, diagnosis and prevention

Introduction: Sepsis accounts for up to one-third of neonatal deaths in the world each year. The World Health Organization acknowledges neonatal sepsis as a major global health concern, and that the highest burden occurs in low- and middle-income countries (LMICs). Despite major research and clinical progress in this area, we still lack accurate diagnostic tools for neonatal sepsis, complicating the management of this condition.Areas covered: The purpose here is to review the latest data on the incidence, diagnosis, prevention, and management of neonatal sepsis in LMIC. We discuss the limitations of current diagnostic tests - including their lack of availability - and how this may influence global estimates of cases. We review the benefits of antenatal, intrapartum, and post-natal preventive measures. We briefly discuss the management, highlighting the emergence of antimicrobial resistance. Finally, we expose some high priority areas.Expert opinion: Neonatal sepsis is a challenging condition requiring a multifaceted approach to address the major diagnostic issues, but also the underlying socio-economic causes that nourish epidemic cases in LMIC. Focusing on antibiotics as a main pillar of intervention is likely to engender antimicrobial resistance, eventually hindering the appreciable gains LMICs have achieved in neonatal health outcomes.