GBS public awareness, advocacy, and prevention—What's working, what's not and why we need a maternal GBS vaccine

"Why has this new vaccine come and for what reasons?" key antecedents and questions for acceptance of a future maternal GBS vaccine: Perspectives of pregnant women, lactating women, and community members in Kenya

Group B streptococcus (GBS) is a leading global cause of neonatal sepsis and meningitis, stillbirth, and puerperal sepsis. While intrapartum antibiotic prophylaxis (IAP) is a currently available GBS disease prevention strategy, IAP is programmatically complex to implement, precluding use in low- and middle-income countries. In Kenya, 2% of stillbirths are attributable to GBS infection. Two maternal GBS vaccines are in late-stage clinical development. However, licensure of a maternal GBS vaccine does not translate into reduction of disease. We conducted 28 in-depth interviews with pregnant people, lactating people, and community members across two counties in Kenya to better understand the attitudes and informational needs of primary vaccine beneficiaries. We identified two emerging themes from the data. The first focused on antecedents to maternal GBS vaccine acceptability. The most common antecedents focused on the vaccine's ability to protect the baby and/or the mother, followed by community sensitization before the vaccine was available. The second key theme focused on questions that would need to be addressed before someone could accept a maternal GBS vaccine. Three key categories of questions were identified, including vaccine safety compared to vaccine benefits, who gets the vaccine, and how the vaccine works. Realizing the potential benefits of a future GBS maternal vaccine will require a multifactorial approach, including ensuring that communities are aware of GBS-related harms as well as the safety and effectiveness of a maternal GBS vaccine. Our study contributes to informing this multifactorial approach by elucidating the attitudes and concerns of key populations.

Stillbirths and Neonatal Deaths Caused by Group B Streptococcus in Africa and South Asia Identified Through Child Health and Mortality Prevention Surveillance (CHAMPS)

Background

Invasive Group B Streptococcus (GBS) is a common cause of early-onset neonatal sepsis and is also associated with stillbirth. This study aimed to determine the proportion of stillborn infants and infants who died between 0 and 90 days attributable to GBS using postmortem minimally invasive tissue sampling (MITS) in 7 low- and middle-income countries (LMICs) participating in Child Health and Mortality Prevention Surveillance (CHAMPS).

Methods

Deaths that occurred between December 2016 and December 2021 were investigated with MITS, including culture for bacteria of blood and cerebrospinal fluid (CSF), multipathogen polymerase chain reaction on blood, CSF, and lung tissue and histopathology of lung, liver, and brain. Data collection included clinical record review and verbal autopsy. Expert panels reviewed all information and assigned causes of death.

Results

We evaluated 2966 deaths, including stillborn infants (n = 1322), infants who died during first day of life (0 to <24 hours, n = 597), early neonatal deaths (END) (1 day to <7 days; END; n = 593), and deaths from 7 to 90 days (n = 454). Group B Streptococcus was determined to be in the causal pathway of death for 2.7% of infants (79 of 2, 966; range, 0.3% in Sierra Leone to 7.2% in South Africa), including 2.3% (31 of 1322) of stillbirths, 4.7% (28 of 597) 0 to <24 hours, 1.9% (11 of 593) END, and 2.0% (9 of 454) of deaths from 7 to 90 days of age. Among deaths attributed to GBS with birth weight data available, 61.9% (39 of 63) of decedents weighed <2500 grams at birth. Group B Streptococcus sepsis was the postmortem diagnosis for 100% (31 of 31) of stillbirths. For deaths <90 days, postmortem diagnoses included GBS sepsis (83.3%, 40 of 48), GBS meningitis (4.2%, 2 of 48), and GBS pneumonia (2.1%, 1 of 48).

Conclusions

Our study reveals significant heterogeneity in the contribution of invasive GBS disease to infant mortality across different countries, emphasizing the need for tailored prevention strategies. Moreover, our findings highlight the substantial impact of GBS on stillbirths, shedding light on a previously underestimated aspect in LMICs.

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.

Group B Streptococcus Screening Guidelines in Pregnancy: A Critical Review of Compliance

INTRODUCTION

Colonization with Group B Streptococcus in pregnancy is a major risk factor for neonatal infection. Universal screening for maternal streptococcal colonization and the use of intrapartum antibiotic prophylaxis has resulted in substantial reductions of neonatal early-onset Group B Streptococcus disease. To achieve the best neonatal outcomes, it is imperative for maternity healthcare providers to adhere to screening and management guidelines.

AIM

This literature review uses a systematic approach and aims to provide a synthesis of what is known about compliance with Group B Streptococcus screening protocols in a variety of global settings, including maternity homes, private obstetric practice, and hospital clinical environments.

METHODS

The review was carried out using electronic databases as well as hand-searching of reference lists. Included papers reported primarily on compliance with Group B Streptococcus screening guidelines, potential factors which influence compliance rates, and implementations and outcomes of interventions.

RESULTS

Six international studies have been retained which all focused on adherence to Group B Streptococcus screening guidelines and demonstrated that different factors might have an influence on adherence to GBS screening protocols such as financial aspects and high caesarean section rates. Findings of relatively low compliance rates led to recognizing the need of developing improved strategies for optimising antenatal GBS screening adherence.

CONCLUSION

Adhering to Group B Streptococcus screening guidelines to prevent neonatal infection is crucial. Various factors influence compliance rates such as financial aspects and high proportions of caesarean sections. The implementation of strategies and different forms of education can result in improved compliance rates.

Impact of late-onset group B streptococcus infection on families: An observational study

OBJECTIVES

Understand the parental impact of having a baby affected by late-onset group B Strep (LOGBS) infection. Understand the social, mental and financial impact on parents/carers or family members of those affected by LOGBS infection. Investigate family information needs and experiences of information provided.

STUDY DESIGN

We devised a 57-item online survey, composing of binary and matrix questions and free text answers. The survey was distributed internationally to families with a baby(ies) affected by LOGBS infection. The questionnaire was designed as a collaborative effort by Group B Strep Support, its medical advisory panel members, midwives, neonatologists, parents and volunteer analysts. Data were collected from June to September in 2018.

RESULTS

531 participants responded. 252 babies (55 %) made a full recovery from their LOGBS infection, 145 (32 %) recovered with long term sequelae and 61 (13 %) died. 126 respondents (32 %) felt there was a minor to substantial impact on their child's day to day life as a consequence of LOGBS infection. 343 respondents (69 %) had not heard about GBS before their child developed LOGBS infection. 338 respondents (77 %) did not receive an information leaflet on GBS. As a result of their child's LOGBS infection, 177 respondents (39 %) experienced either minor or substantial financial difficulty and 314 respondents (70 %) felt that their own or a family member's mental health was affected. 300 respondents (66 %) experienced problems with planning or reduced enjoyment of subsequent pregnancies. 102 respondents (29 %) reported their other children experienced difficulty due to their sibling's LOGBS infection.

CONCLUSIONS

The results of our study provide a novel insight into families' experiences following a baby affected by LOGBS infection. Study findings suggests that families suffer significant financial and psychological difficulties as a result of LOGBS infection. Furthermore, information needs are frequently being left unmet.

Streptococcus agalactiae in pregnant women in Brazil: prevalence, serotypes, and antibiotic resistance

Brazilian data for maternal GBS colonization shows different prevalence rates. This conflicting data may be related to the absence of an official recommendation from the Federal Brazilian Health Authorities describing guidelines and protocols to perform GBS screening in pregnant women, in both public and private clinics. In the present review, we evaluated published reports addressing the prevalence of GBS in different regions of the country, methods used, and, when available, information regarding antibiotic resistance and serological typing of clinical isolates. According to this review, GBS prevalence in pregnant women in Brazil ranged from 4.2 to 28.4%, in the last 10 years. Serotype Ia was the most prevalent. The highest antibiotic resistance rates were found for tetarcycline, although its use to treat GBS infections is not common. Our results also show high resistance rates to clindamycin and erythromycin, which are commonly used as an alternative to penicillin in GBS infecctions. The increased antibiotic resistance, variations in serotype distribution, and high GBS prevalences need to be further investigated. Based on the present situation, recommendations regarding GBS surveillance in the country were raised and may improve our strategies for preventing neonatal infections.

Perinatal Group B Streptococcal Infections: Virulence Factors, Immunity, and Prevention Strategies

Group B streptococcus (GBS) or Streptococcus agalactiae is a β-hemolytic, Gram-positive bacterium that is a leading cause of neonatal infections. GBS commonly colonizes the lower gastrointestinal and genital tracts and, during pregnancy, neonates are at risk of infection. Although intrapartum antibiotic prophylaxis during labor and delivery has decreased the incidence of early-onset neonatal infection, these measures do not prevent ascending infection that can occur earlier in pregnancy leading to preterm births, stillbirths, or late-onset neonatal infections. Prevention of GBS infection in pregnancy is complex and is likely influenced by multiple factors, including pathogenicity, host factors, vaginal microbiome, false-negative screening, and/or changes in antibiotic resistance. A deeper understanding of the mechanisms of GBS infections during pregnancy will facilitate the development of novel therapeutics and vaccines. Here, we summarize and discuss important advancements in our understanding of GBS vaginal colonization, ascending infection, and preterm birth.

Preventing group B streptococcal infections in newborns

Despite advances in intrapartum antibiotic prophylaxis (IAP), group B streptococcal infection continues to be a predominant cause of early-onset disease in neonates. About 2% of neonates exposed to group B Streptococcus develop clinical manifestations including sepsis, pneumonia, and meningitis. Screening in late pregnancy reduces the incidence of early-onset sepsis by more than 80%. Clinicians must be able to identify the risk factors and clinical manifestations of group B streptococcal infection and to understand management and prevention guidelines.

Current management and long-term outcomes following chorioamnionitis

Chorioamnionitis is the process of active infection within the amniotic cavity that induces an inflammatory response. A wide variety of pathologic organisms can cause chorioamnionitis. Prompt diagnosis and timely treatment with broad-spectrum antibiotics can help avert the significant short-term and long-term consequences that may result. This review aims to summarize the up-to-date diagnosis criteria, treatment protocols, and long-term sequelae of missed diagnoses or poorly treated disease. It also calls for future studies that aim to better understand the mechanism of disease and to develop better detection and intervention methods to prevent the significant associated morbidity.

Perinatal vertical transmission of antibiotic-resistant bacteria: a systematic review and proposed research strategy

BACKGROUND

Antibiotic-resistant bacteria contribute to both early- and late-onset sepsis and outbreaks in neonatal intensive care units (NICUs). The extent to which vertical transmission of these resistant bacteria contributes to colonisation or infection of vulnerable infants in NICUs is unclear. Risk factors for vertical transmission of antibiotic-resistant bacteria are not well described.

OBJECTIVES

To identify studies describing vertical transmission of antibiotic-resistant bacteria, risk factors for transmission and the impact of colonisation on neonatal outcomes.

SEARCH STRATEGY

EMBASE, CINAHL, Cochrane, PubMed, and MEDLINE databases were searched using selected terminology. Titles and abstracts were screened by two reviewers. Selected papers were reviewed in full by two individuals to ascertain whether they fulfilled the inclusion criteria.

SELECTION CRITERIA

Any original article investigating perinatal vertical transmission of antibiotic-resistant bacteria between a mother and neonate was included.

DATA COLLECTION AND ANALYSIS

Data were extracted on study design, organism, antibiotic resistance, and means of ascertaining vertical transmission.

MAIN RESULTS

Five papers out of 4839 titles fulfilled the inclusion criteria. Four studies were predominantly observational and one was a case report. Each demonstrated perinatal transmission. No study reported risk factors for the transmission of resistant bacteria or the impact of colonisation on neonatal outcomes.

AUTHOR'S CONCLUSIONS

There is an absence of research into the perinatal transmission of resistant organisms despite the potential implications of such a situation. We outline objectives that need to be addressed in future research and describe a study design to ascertain the prevalence and risk factors for vertical transmission.