Learning from each other in the COVID-19 pandemic

The increase in cases of coronavirus disease 2019 (COVID-19) worldwide has been paralleled by increasing information, and misinformation. Accurate public health messaging is essential to counter this, but education may also have a role. Early in the outbreak, The London School of Hygiene & Tropical Medicine partnered with FutureLearn to develop a massive open online course (MOOC) on COVID-19. Our approach was grounded in social constructivism, supporting participation, sharing uncertainties, and encouraging discussion. The first run of the course included over 200,000 participants from 184 countries, with over 88,000 comments at the end of the three-week run. Many participants supported each other's learning in their responses and further questions. Our experience suggests that open education, and supporting the development of communities of learners, can complement traditional messaging, providing a sustainable approach to countering the spread of misinformation.

Congenital microcephaly unrelated to flavivirus exposure in coastal Kenya

Background: Zika virus (ZIKV) was first discovered in East Africa in 1947.  ZIKV has caused microcephaly in the Americas, but it is not known whether ZIKV is a cause of microcephaly in East Africa. Methods: We used surveillance data from 11,061 live births at Kilifi County Hospital in coastal Kenya between January 2012 and October 2016 to identify microcephaly cases and conducted a nested case-control study to determine risk factors for microcephaly. Gestational age at birth was estimated based on antenatal ultrasound scanning ('Scanned cohort') or last menstrual period ('LMP cohort', including births ≥37 weeks' gestation only). Controls were newborns with head circumference Z scores between >-2 and ≤2 SD that were compared to microcephaly cases in relation to ZIKV exposure and other maternal and newborn factors. Results: Of the 11,061 newborns, 214 (1.9%, 95%CI 1.69, 2.21) had microcephaly. Microcephaly prevalence was 1.0% (95%CI 0.64, 1.70, n=1529) and 2.1% (95%CI 1.81, 2.38, n=9532) in the scanned and LMP cohorts, respectively. After excluding babies <2500 g (n=1199) in the LMP cohort the prevalence was 1.1% (95%CI 0.93, 1.39). Microcephaly showed an association with being born small for gestational age (p<0.001) but not with ZIKV neutralising antibodies (p=0.6) or anti-ZIKV NS1 IgM response (p=0.9). No samples had a ZIKV neutralising antibody titre that was at least fourfold higher than the corresponding dengue virus (DENV) titre. No ZIKV or other flavivirus RNA was detected in cord blood from cases or controls. Conclusions: Microcephaly was prevalent in coastal Kenya, but does not appear to be related to ZIKV exposure; the ZIKV response observed in our study population was largely due to cross-reactive responses to DENV or other related flaviviruses. Further research into potential causes and the clinical consequences of microcephaly in this population is urgently needed.

Protocol for a randomised trial of early kangaroo mother care compared to standard care on survival of pre-stabilised preterm neonates in The Gambia (eKMC)

BACKGROUND

Complications of preterm birth cause more than 1 million deaths each year, mostly within the first day after birth (47%) and before full post-natal stabilisation. Kangaroo mother care (KMC), provided as continuous skin-to-skin contact for 18 h per day to fully stabilised neonates ≤ 2000 g, reduces mortality by 36-51% at discharge or term-corrected age compared with incubator care. The mortality effect of starting continuous KMC before stabilisation is a priority evidence gap, which we aim to investigate in the eKMC trial, with a secondary aim of understanding mechanisms, particularly for infection prevention.

METHODS

We will conduct a single-site, non-blinded, individually randomised, controlled trial comparing two parallel groups to either early (within 24 h of admission) continuous KMC or standard care on incubator or radiant heater with KMC when clinically stable at > 24 h of admission. Eligible neonates (n = 392) are hospitalised singletons or twins < 2000 g and 1-24 h old at screening who are mild to moderately unstable as per a trial definition using cardio-respiratory parameters. Randomisation is stratified by weight category (< 1200 g; ≥ 1200 g) and in random permuted blocks of varying sizes with allocation of twins to the same arm. Participants are followed up to 28 ± 5 days of age with regular inpatient assessments plus criteria-led review in the event of clinical deterioration. The primary outcome is all-cause neonatal mortality by age 28 days. Secondary outcomes include the time to death, cardio-respiratory stability, hypothermia, exclusive breastfeeding at discharge, weight gain at age 28 days, clinically suspected infection (age 3 to 28 days), intestinal carriage of extended-spectrum beta-lactamase producing (ESBL) Klebsiella pneumoniae (age 28 days), and duration of the hospital stay. Intention-to-treat analysis will be applied for all outcomes, adjusting for twin gestation.

DISCUSSION

This is one of the first clinical trials to examine the KMC mortality effect in a pre-stabilised preterm population. Our findings will contribute to the global evidence base in addition to providing insights into the infection prevention mechanisms and safety of using this established intervention for the most vulnerable neonatal population.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03555981. Submitted 8 May 2018 and registered 14 June 2018. Prospectively registered.

Vaccines for maternal immunization against Group B Streptococcus disease: WHO perspectives on case ascertainment and case definitions

Group B Streptococcus (GBS) is an important cause of disease in young infants, stillbirths, pregnant and post-partum women. GBS vaccines for maternal immunization are in development aiming to reduce this burden. Standardisation of case definitions and ascertainment methodologies for GBS disease is needed to support future trials of maternal GBS vaccines. Considerations presented here may also serve to promote consistency in observational studies and surveillance, to better establish disease burden. The World Health Organization convened a working group to provide consensus guidance for case ascertainment and case definitions of GBS disease in stillbirths, infants, pregnant and post-partum women, with feedback sought from external stakeholders. In intervention studies, case capture and case ascertainment for GBS disease should be based on antenatal recruitment of women, with active follow-up, systematic clinical assessment, standardised sampling strategies and optimised laboratory methods. Confirmed cases of invasive GBS disease in stillbirths or infants should be included in a primary composite endpoint for vaccine efficacy studies, with GBS cultured from a usually sterile body site (may be post-mortem). For additional endpoints, or observational studies, confirmed cases of GBS sepsis in pregnant and post-partum women should be assessed. Culture independent diagnostic tests (CIDTs) may detect additional presumed cases, however, the use of these diagnostics needs further evaluation. Efficacy of vaccination against maternal and neonatal GBS colonisation, and maternal GBS urinary tract infection could be included as additional, separate, endpoints and/or in observational studies. Whilst the focus here is on specific GBS disease outcomes, intervention studies also present an opportunity to establish the contribution of GBS across adverse perinatal outcomes, including all-cause stillbirth, preterm birth and neonatal encephalopathy.

Atlas of group A streptococcal vaccine candidates compiled using large-scale comparative genomics

Group A Streptococcus (GAS; Streptococcus pyogenes) is a bacterial pathogen for which a commercial vaccine for humans is not available. Employing the advantages of high-throughput DNA sequencing technology to vaccine design, we have analyzed 2,083 globally sampled GAS genomes. The global GAS population structure reveals extensive genomic heterogeneity driven by homologous recombination and overlaid with high levels of accessory gene plasticity. We identified the existence of more than 290 clinically associated genomic phylogroups across 22 countries, highlighting challenges in designing vaccines of global utility. To determine vaccine candidate coverage, we investigated all of the previously described GAS candidate antigens for gene carriage and gene sequence heterogeneity. Only 15 of 28 vaccine antigen candidates were found to have both low naturally occurring sequence variation and high (>99%) coverage across this diverse GAS population. This technological platform for vaccine coverage determination is equally applicable to prospective GAS vaccine antigens identified in future studies.

Risk of Early-Onset Neonatal Group B Streptococcal Disease With Maternal Colonization Worldwide: Systematic Review and Meta-analyses

Background

Early-onset group B streptococcal disease (EOGBS) occurs in neonates (days 0-6) born to pregnant women who are rectovaginally colonized with group B Streptococcus (GBS), but the risk of EOGBS from vertical transmission has not been systematically reviewed. This article, the seventh in a series on the burden of GBS disease, aims to estimate this risk and how it varies with coverage of intrapartum antibiotic prophylaxis (IAP), used to reduce the incidence of EOGBS.

Methods

We conducted systematic reviews (Pubmed/Medline, Embase, Latin American and Caribbean Health Sciences Literature (LILACS), World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data from investigator groups on maternal GBS colonization and neonatal outcomes. We included articles with ≥200 GBS colonized pregnant women that reported IAP coverage. We did meta-analyses to determine pooled estimates of risk of EOGBS, and examined the association in risk of EOGBS with IAP coverage.

Results

We identified 30 articles including 20328 GBS-colonized pregnant women for inclusion. The risk of EOGBS in settings without an IAP policy was 1.1% (95% confidence interval [CI], .6%-1.5%). As IAP increased, the risk of EOGBS decreased, with a linear association. Based on linear regression, the risk of EOGBS in settings with 80% IAP coverage was predicted to be 0.3% (95% CI, 0-.9).

Conclusions

The risk of EOGBS among GBS-colonized pregnant women, from this first systematic review, is consistent with previous estimates from single studies (1%-2%). Increasing IAP coverage was linearly associated with decreased risk of EOGBS disease.

Infant Group B Streptococcal Disease Incidence and Serotypes Worldwide: Systematic Review and Meta-analyses

Background

Group B Streptococcus (GBS) remains a leading cause of neonatal sepsis in high-income contexts, despite declines due to intrapartum antibiotic prophylaxis (IAP). Recent evidence suggests higher incidence in Africa, where IAP is rare. We investigated the global incidence of infant invasive GBS disease and the associated serotypes, updating previous estimates.

Methods

We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data regarding invasive GBS disease in infants aged 0–89 days. We conducted random-effects meta-analyses of incidence, case fatality risk (CFR), and serotype prevalence.

Results

We identified 135 studies with data on incidence (n = 90), CFR (n = 64), or serotype (n = 45). The pooled incidence of invasive GBS disease in infants was 0.49 per 1000 live births (95% confidence interval [CI], .43–.56), and was highest in Africa (1.12) and lowest in Asia (0.30). Early-onset disease incidence was 0.41 (95% CI, .36–.47); late-onset disease incidence was 0.26 (95% CI, .21–.30). CFR was 8.4% (95% CI, 6.6%–10.2%). Serotype III (61.5%) dominated, with 97% of cases caused by serotypes Ia, Ib, II, III, and V.

Conclusions

The incidence of infant GBS disease remains high in some regions, particularly Africa. We likely underestimated incidence in some contexts, due to limitations in case ascertainment and specimen collection and processing. Burden in Asia requires further investigation.

Stillbirth With Group B Streptococcus Disease Worldwide: Systematic Review and Meta-analyses

Background

There are an estimated 2.6 million stillbirths each year, many of which are due to infections, especially in low- and middle-income contexts. This paper, the eighth in a series on the burden of group B streptococcal (GBS) disease, aims to estimate the percentage of stillbirths associated with GBS disease.

Methods

We conducted systematic literature reviews (PubMed/Medline, Embase, Literatura Latino-Americana e do Caribe em Ciências da Saúde, World Health Organization Library Information System, and Scopus) and sought unpublished data from investigator groups. Studies were included if they reported original data on stillbirths (predominantly ≥28 weeks’ gestation or ≥1000 g, with GBS isolated from a sterile site) as a percentage of total stillbirths. We did meta-analyses to derive pooled estimates of the percentage of GBS-associated stillbirths, regionally and worldwide for recent datasets.

Results

We included 14 studies from any period, 5 with recent data (after 2000). There were no data from Asia. We estimated that 1% (95% confidence interval [CI], 0–2%) of all stillbirths in developed countries and 4% (95% CI, 2%–6%) in Africa were associated with GBS.

Conclusions

GBS is likely an important cause of stillbirth, especially in Africa. However, data are limited in terms of geographic spread, with no data from Asia, and cases worldwide are probably underestimated due to incomplete case ascertainment. More data, using standardized, systematic methods, are critical, particularly from low- and middle-income contexts where the highest burden of stillbirths occurs. These data are essential to inform interventions, such as maternal GBS vaccination.

Serious bacterial infections in neonates: improving reporting and case definitions

Neonatal infections affect about 7 million neonates causing over 600 000 deaths every year. Estimating the burden is challenging as there are multiple reporting criteria and definitions for serious bacterial infections in neonates. Essential criteria for reporting serious neonatal bacterial infections have recently been published as the STROBE-NI checklist and, in the context of maternal vaccination, definitions have been published by the Brighton Collaboration Global Alignment of Immunization safety Assessment in pregnancy (GAIA) project. Standardisation of reporting criteria is essential to allow data comparability. This an important step in providing a clearer picture of the burden of serious bacterial infections in neonates and a welcome progress for guiding new investments in interventions.

Estimates of the Burden of Group B Streptococcal Disease Worldwide for Pregnant Women, Stillbirths, and Children

BACKGROUND

We aimed to provide the first comprehensive estimates of the burden of group B Streptococcus (GBS), including invasive disease in pregnant and postpartum women, fetal infection/stillbirth, and infants. Intrapartum antibiotic prophylaxis is the current mainstay of prevention, reducing early-onset infant disease in high-income contexts. Maternal GBS vaccines are in development.

METHODS

For 2015 live births, we used a compartmental model to estimate (1) exposure to maternal GBS colonization, (2) cases of infant invasive GBS disease, (3) deaths, and (4) disabilities. We applied incidence or prevalence data to estimate cases of maternal and fetal infection/stillbirth, and infants with invasive GBS disease presenting with neonatal encephalopathy. We applied risk ratios to estimate numbers of preterm births attributable to GBS. Uncertainty was also estimated.

RESULTS

Worldwide in 2015, we estimated 205000 (uncertainty range [UR], 101000-327000) infants with early-onset disease and 114000 (UR, 44000-326000) with late-onset disease, of whom a minimum of 7000 (UR, 0-19000) presented with neonatal encephalopathy. There were 90000 (UR, 36000-169000) deaths in infants <3 months age, and, at least 10000 (UR, 3000-27000) children with disability each year. There were 33000 (UR, 13000-52000) cases of invasive GBS disease in pregnant or postpartum women, and 57000 (UR, 12000-104000) fetal infections/stillbirths. Up to 3.5 million preterm births may be attributable to GBS. Africa accounted for 54% of estimated cases and 65% of all fetal/infant deaths. A maternal vaccine with 80% efficacy and 90% coverage could prevent 107000 (UR, 20000-198000) stillbirths and infant deaths.

CONCLUSIONS

Our conservative estimates suggest that GBS is a leading contributor to adverse maternal and newborn outcomes, with at least 409000 (UR, 144000-573000) maternal/fetal/infant cases and 147000 (UR, 47000-273000) stillbirths and infant deaths annually. An effective GBS vaccine could reduce disease in the mother, the fetus, and the infant.

Neurodevelopmental Impairment in Children After Group B Streptococcal Disease Worldwide: Systematic Review and Meta-analyses

BACKGROUND

Survivors of infant group B streptococcal (GBS) disease are at risk of neurodevelopmental impairment (NDI), a burden not previously systematically quantified. This is the 10th of 11 articles estimating the burden of GBS disease. Here we aimed to estimate NDI in survivors of infant GBS disease.

METHODS

We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data on the risk of NDI after invasive GBS disease in infants <90 days of age. We did meta-analyses to derive pooled estimates of the percentage of infants with NDI following GBS meningitis.

RESULTS

We identified 6127 studies, of which 18 met eligibility criteria, all from middle- or high-income contexts. All 18 studies followed up survivors of GBS meningitis; only 5 of these studies also followed up survivors of GBS sepsis and were too few to pool in a meta-analysis. Of meningitis survivors, 32% (95% CI, 25%-38%) had NDI at 18 months of follow-up, including 18% (95% CI, 13%-22%) with moderate to severe NDI.

CONCLUSIONS

GBS meningitis is an important risk factor for moderate to severe NDI, affecting around 1 in 5 survivors. However, data are limited, and we were unable to estimate NDI after GBS sepsis. Comparability of studies is difficult due to methodological differences including variability in timing of clinical reviews and assessment tools. Follow-up of clinical cases and standardization of methods are essential to fully quantify the total burden of NDI associated with GBS disease, and inform program priorities.

Maternal Colonization With Group B Streptococcus and Serotype Distribution Worldwide: Systematic Review and Meta-analyses

BACKGROUND

Maternal rectovaginal colonization with group B Streptococcus (GBS) is the most common pathway for GBS disease in mother, fetus, and newborn. This article, the second in a series estimating the burden of GBS, aims to determine the prevalence and serotype distribution of GBS colonizing pregnant women worldwide.

METHODS

We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus), organized Chinese language searches, and sought unpublished data from investigator groups. We applied broad inclusion criteria to maximize data inputs, particularly from low- and middle-income contexts, and then applied new meta-analyses to adjust for studies with less-sensitive sampling and laboratory techniques. We undertook meta-analyses to derive pooled estimates of maternal GBS colonization prevalence at national and regional levels.

RESULTS

The dataset regarding colonization included 390 articles, 85 countries, and a total of 299924 pregnant women. Our adjusted estimate for maternal GBS colonization worldwide was 18% (95% confidence interval [CI], 17%-19%), with regional variation (11%-35%), and lower prevalence in Southern Asia (12.5% [95% CI, 10%-15%]) and Eastern Asia (11% [95% CI, 10%-12%]). Bacterial serotypes I-V account for 98% of identified colonizing GBS isolates worldwide. Serotype III, associated with invasive disease, accounts for 25% (95% CI, 23%-28%), but is less frequent in some South American and Asian countries. Serotypes VI-IX are more common in Asia.

CONCLUSIONS

GBS colonizes pregnant women worldwide, but prevalence and serotype distribution vary, even after adjusting for laboratory methods. Lower GBS maternal colonization prevalence, with less serotype III, may help to explain lower GBS disease incidence in regions such as Asia. High prevalence worldwide, and more serotype data, are relevant to prevention efforts.

Intrapartum Antibiotic Chemoprophylaxis Policies for the Prevention of Group B Streptococcal Disease Worldwide: Systematic Review

BACKGROUND

Intrapartum antibiotic chemoprophylaxis (IAP) prevents most early-onset group B streptococcal (GBS) disease. However, there is no description of how IAP is used around the world. This article is the sixth in a series estimating the burden of GBS disease. Here we aimed to review GBS screening policies and IAP implementation worldwide.

METHODS

We identified data through (1) systematic literature reviews (PubMed/Medline, Embase, Literature in the Health Sciences in Latin America and the Caribbean [LILACS], World Health Organization library database [WHOLIS], and Scopus) and unpublished data from professional societies and (2) an online survey and searches of policies from medical societies and professionals. We included data on whether an IAP policy was in use, and if so whether it was based on microbiological or clinical risk factors and how these were applied, as well as the estimated coverage (percentage of women receiving IAP where indicated).

RESULTS

We received policy information from 95 of 195 (49%) countries. Of these, 60 of 95 (63%) had an IAP policy; 35 of 60 (58%) used microbiological screening, 25 of 60 (42%) used clinical risk factors. Two of 15 (13%) low-income, 4 of 16 (25%) lower-middle-income, 14 of 20 (70%) upper-middle-income, and 40 of 44 (91%) high-income countries had any IAP policy. The remaining 35 of 95 (37%) had no national policy (25/33 from low-income and lower-middle-income countries). Coverage varied considerably; for microbiological screening, median coverage was 80% (range, 20%-95%); for clinical risk factor-based screening, coverage was 29% (range, 10%-50%). Although there were differences in the microbiological screening methods employed, the individual clinical risk factors used were similar.

CONCLUSIONS

There is considerable heterogeneity in IAP screening policies and coverage worldwide. Alternative global strategies, such as maternal vaccination, are needed to enhance the scope of global prevention of GBS disease.

Group B Streptococcal Disease Worldwide for Pregnant Women, Stillbirths, and Children: Why, What, and How to Undertake Estimates?

Improving maternal, newborn, and child health is central to Sustainable Development Goal targets for 2030, requiring acceleration especially to prevent 5.6 million deaths around the time of birth. Infections contribute to this burden, but etiological data are limited. Group B Streptococcus (GBS) is an important perinatal pathogen, although previously focus has been primarily on liveborn children, especially early-onset disease. In this first of an 11-article supplement, we discuss the following: (1) Why estimate the worldwide burden of GBS disease? (2) What outcomes of GBS in pregnancy should be included? (3) What data and epidemiological parameters are required? (4) What methods and models can be used to transparently estimate this burden of GBS? (5) What are the challenges with available data? and (6) How can estimates address data gaps to better inform GBS interventions including maternal immunization? We review all available GBS data worldwide, including maternal GBS colonization, risk of neonatal disease (with/without intrapartum antibiotic prophylaxis), maternal GBS disease, neonatal/infant GBS disease, and subsequent impairment, plus GBS-associated stillbirth, preterm birth, and neonatal encephalopathy. We summarize our methods for searches, meta-analyses, and modeling including a compartmental model. Our approach is consistent with the World Health Organization (WHO) Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER), published in The Lancet and the Public Library of Science (PLoS). We aim to address priority epidemiological gaps highlighted by WHO to inform potential maternal vaccination.

Maternal Disease With Group B Streptococcus and Serotype Distribution Worldwide: Systematic Review and Meta-analyses

BACKGROUND

Infections such as group B Streptococcus (GBS) are an important cause of maternal sepsis, yet limited data on epidemiology exist. This article, the third of 11, estimates the incidence of maternal GBS disease worldwide.

METHODS

We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data on invasive GBS disease in women pregnant or within 42 days postpartum. We undertook meta-analyses to derive pooled estimates of the incidence of maternal GBS disease. We examined maternal and perinatal outcomes and GBS serotypes.

RESULTS

Fifteen studies and 1 unpublished dataset were identified, all from United Nations-defined developed regions. From a single study with pregnancies as the denominator, the incidence of maternal GBS disease was 0.38 (95% confidence interval [CI], .28-.48) per 1000 pregnancies. From 3 studies reporting cases by the number of maternities (pregnancies resulting in live/still birth), the incidence was 0.23 (95% CI, .09-.37). Five studies reported serotypes, with Ia being the most common (31%). Most maternal GBS disease was detected at or after delivery.

CONCLUSIONS

Incidence data on maternal GBS disease in developing regions are lacking. In developed regions the incidence is low, as are the sequelae for the mother, but the risk to the fetus and newborn is substantial. The timing of GBS disease suggests that a maternal vaccine given in the late second or early third trimester of pregnancy would prevent most maternal cases.

Neonatal Encephalopathy With Group B Streptococcal Disease Worldwide: Systematic Review, Investigator Group Datasets, and Meta-analysis

BACKGROUND

Neonatal encephalopathy (NE) is a leading cause of child mortality and longer-term impairment. Infection can sensitize the newborn brain to injury; however, the role of group B streptococcal (GBS) disease has not been reviewed. This paper is the ninth in an 11-article series estimating the burden of GBS disease; here we aim to assess the proportion of GBS in NE cases.

METHODS

We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data from investigator groups reporting GBS-associated NE. Meta-analyses estimated the proportion of GBS disease in NE and mortality risk. UK population-level data estimated the incidence of GBS-associated NE.

RESULTS

Four published and 25 unpublished datasets were identified from 13 countries (N = 10436). The proportion of NE associated with GBS was 0.58% (95% confidence interval [CI], 0.18%-.98%). Mortality was significantly increased in GBS-associated NE vs NE alone (risk ratio, 2.07 [95% CI, 1.47-2.91]). This equates to a UK incidence of GBS-associated NE of 0.019 per 1000 live births.

CONCLUSIONS

The consistent increased proportion of GBS disease in NE and significant increased risk of mortality provides evidence that GBS infection contributes to NE. Increased information regarding this and other organisms is important to inform interventions, especially in low- and middle-resource contexts.

Preterm Birth Associated With Group B Streptococcus Maternal Colonization Worldwide: Systematic Review and Meta-analyses

BACKGROUND

Preterm birth complications are the leading cause of deaths among children <5 years of age. Studies have suggested that group B Streptococcus (GBS) maternal rectovaginal colonization during pregnancy may be a risk factor for preterm delivery. This article is the fifth of 11 in a series. We aimed to assess the association between GBS maternal colonization and preterm birth in order to inform estimates of the burden of GBS.

METHODS

We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data from investigator groups on the association of preterm birth (<37 weeks' gestation) and maternal GBS colonization (GBS isolation from vaginal, cervical, and/or rectal swabs; with separate subanalysis on GBS bacteriuria). We did meta-analyses to derive pooled estimates of the risk and odds ratios (according to study design), with sensitivity analyses to investigate potential biases.

RESULTS

We identified 45 studies for inclusion. We estimated the risk ratio (RR) for preterm birth with maternal GBS colonization to be 1.21 (95% confidence interval [CI], .99-1.48; P = .061) in cohort and cross-sectional studies, and the odds ratio to be 1.85 (95% CI, 1.24-2.77; P = .003) in case-control studies. Preterm birth was associated with GBS bacteriuria in cohort studies (RR, 1.98 [95% CI, 1.45-2.69]; P < .001).

CONCLUSIONS

From this review, there is evidence to suggest that preterm birth is associated with maternal GBS colonization, especially where there is evidence of ascending infection (bacteriuria). Several biases reduce the chance of detecting an effect. Equally, however, results, including evidence for the association, may be due to confounding, which is rarely addressed in studies. Assessment of any effect on preterm delivery should be included in future maternal GBS vaccine trials.

Should First-line Empiric Treatment Strategies for Neonates Cover Coagulase-negative Staphylococcal Infections in Kenya?

BACKGROUND

Neonatal mortality remains high in sub-Saharan Africa, and a third of deaths are estimated to result from infection. While coagulase-negative staphylococci (CoNS) are leading neonatal pathogens in resource-rich settings, their role, and the need for early anti-Staphylococcal treatment in empiric antibiotic guidelines, is unknown in sub-Saharan Africa.

METHODS

We examined systematic clinical and microbiologic surveillance data from all neonatal admissions to Kilifi County Hospital (1998-2013) to determine associated case fatality and/or prolonged duration of admission associated with CoNS in neonates treated according to standard World Health Organization guidelines.

RESULTS

CoNS was isolated from blood culture in 995 of 9552 (10%) neonates. Case fatality among neonates with CoNS isolated from blood did not differ from other neonatal admissions (P = 0.2), and duration of admission was not prolonged [odds ratio (OR) = 0.9 (0.7-1.0), P = 0.040]. Neonates with CoNS were more likely to have convulsions [OR = 1.4 (1.0-1.8), P = 0.031] but less likely to have impaired consciousness or severe indrawing [OR = 0.8 (0.7-0.9), P = 0.025; OR = 0.9 (0.7-1.0), P = 0.065].

CONCLUSIONS

CoNS isolation in blood cultures at admission was not associated with adverse clinical outcomes in neonates treated according to standard World Health Organization guidelines for hospital care in this setting. There is no evidence that first-line antimicrobial treatment guidelines should be altered to increase cover for CoNS infections in neonates in this setting.

AMR Surveillance in low and middle-income settings - A roadmap for participation in the Global Antimicrobial Surveillance System (GLASS)

Drug-resistant infections caused by bacteria with increasing antimicrobial resistance (AMR) threaten our ability to treat life-threatening conditions. Tackling AMR requires international collaboration and partnership. An early and leading priority to do this is to strengthen AMR surveillance, particularly in low-income countries where the burden of infectious diseases is highest and where data are most limited. The World Health Organization (WHO) has developed the Global AMR Surveillance System (GLASS) as one of a number of measures designed to tackle the problem of AMR, and WHO member states have been encouraged to produce National Action Plans for AMR by 2017. However, low-income countries are unlikely to have the resources or capacity to implement all the components in the GLASS manual. To facilitate their efforts, we developed a guideline that is aligned to the GLASS procedures, but written specifically for implementation in low-income countries. The guideline allows for flexibility across different systems, but has sufficient standardisation of core protocols to ensure that, if followed, data will be valid and comparable. This will ensure that the surveillance programme can provide health intelligence data to inform evidence-based interventions at local, national and international levels.

Supporting surveillance capacity for antimicrobial resistance: Laboratory capacity strengthening for drug resistant infections in low and middle income countries

Development of antimicrobial resistance (AMR) threatens our ability to treat common and life threatening infections. Identifying the emergence of AMR requires strengthening of surveillance for AMR, particularly in low and middle-income countries (LMICs) where the burden of infection is highest and health systems are least able to respond. This work aimed, through a combination of desk-based investigation, discussion with colleagues worldwide, and visits to three contrasting countries (Ethiopia, Malawi and Vietnam), to map and compare existing models and surveillance systems for AMR, to examine what worked and what did not work. Current capacity for AMR surveillance varies in LMICs, but and systems in development are focussed on laboratory surveillance. This approach limits understanding of AMR and the extent to which laboratory results can inform local, national and international public health policy. An integrated model, combining clinical, laboratory and demographic surveillance in sentinel sites is more informative and costs for clinical and demographic surveillance are proportionally much lower. The speed and extent to which AMR surveillance can be strengthened depends on the functioning of the health system, and the resources available. Where there is existing laboratory capacity, it may be possible to develop 5-20 sentinel sites with a long term view of establishing comprehensive surveillance; but where health systems are weaker and laboratory infrastructure less developed, available expertise and resources may limit this to 1-2 sentinel sites. Prioritising core functions, such as automated blood cultures, reduces investment at each site. Expertise to support AMR surveillance in LMICs may come from a variety of international, or national, institutions. It is important that these organisations collaborate to support the health systems on which AMR surveillance is built, as well as improving technical capacity specifically relating to AMR surveillance. Strong collaborations, and leadership, drive successful AMR surveillance systems across countries and contexts.

Should first-line empiric treatment strategies cover coagulase-negative staphylococcal infections in severely malnourished or HIV-infected children in Kenya?

Background

Bloodstream infection is a common cause of morbidity in children aged <5 years in developing countries. In studies reporting bacteremia in Africa, coagulase-negative Staphylococci (CoNS) are commonly isolated. However, it is currently unclear whether children who are highly susceptible to infection because of severe acute malnutrition (SAM) or HIV should be treated with antimicrobials specifically to cover CoNS. We aimed to determine the clinical significance of CoNS amongst children admitted to a rural hospital in Kenya in relation to nutritional and HIV status.

Methods

Systematically collected clinical and microbiological surveillance data from children aged 6–59 months admitted to Kilifi County Hospital (2007–2013) were analysed. Multivariable regression was used to test associations between CoNS isolation from blood cultures and SAM (MUAC <11.5cm or nutritional oedema (kwashiorkor)), and HIV serostatus; and among children with SAM or HIV, associations between CoNS isolation and mortality, duration of hospitalization and clinical features.

Results

CoNS were isolated from blood culture in 906/13,315 (6.8%) children, of whom 135/906 (14.9%) had SAM and 54/906 (6.0%) were HIV antibody positive. CoNS isolation was not associated with SAM (MUAC<11.5cm (aOR 1.11, 95% CI 0.88–1.40) or kwashiorkor (aOR 0.84, 95% CI 0.48–1.49)), or a positive HIV antibody test (aOR 1.25, 95% CI 0.92–1.71). Among children with SAM or a positive HIV antibody test, CoNS isolation was not associated with mortality or prolonged hospitalization.

Conclusion

In a large, systematic study, there was no evidence that antimicrobial therapy should specifically target CoNS amongst children with SAM or HIV-infection or exposure.

Invasive Group A Streptococcus Infection among Children, Rural Kenya

These infections cause serious illness, especially in neonates.

To determine the extent of group A Streptococcus (GAS) infections in sub-Saharan Africa and the serotypes that cause disease, we analyzed surveillance data for 64,741 hospital admissions in Kilifi, Kenya, during 1998–2011. We evaluated incidence, clinical presentations, and emm types that cause invasive GAS infection. We detected 370 cases; of the 369 for which we had data, most were skin and soft tissue infections (70%), severe pneumonia (23%), and primary bacteremia (14%). Overall case-fatality risk was 12%. Incidence of invasive GAS infection was 0.6 cases/1,000 live births among neonates, 101/100,000 person-years among children <1 year of age, and 35/100,000 among children <5 years of age. Genome sequencing identified 88 emm types. GAS causes serious disease in children in rural Kenya, especially neonates, and the causative organisms have considerable genotypic diversity. Benefit from the most advanced GAS type–specific vaccines may be limited, and efforts must be directed to protect against disease in regions of high incidence.