Early BCG vaccine to low-birth-weight infants and the effects on growth in the first year of life: a randomised controlled trial

Assessment of adherence to pre-vaccination precautions and AEFI reporting practices during BCG vaccination in 4 hospitals in Ghana

The BCG vaccine, like all other vaccines, is associated with adverse events following immunization (AEFI). Reducing the incidence of AEFI is crucial in reposing confidence in BCG vaccination and reducing hesitancy associated with the vaccine. This requires safety precautions before and during vaccinations, as well as reporting AEFIs after vaccination. This study assessed the adherence of health-care professionals to pre-vaccination precautions and adverse events following immunization (AEFI) reporting practices during BCG vaccination in four hospitals in Ghana. It is hoped that the findings of the study will serve as a baseline to identify gaps for further studies to generate a stronger evidence for policy formulation aimed at improving BCG vaccine safety in Ghana and other tuberculosis endemic countries. A cross-sectional study design was employed, and Statistical Package for Social Sciences, IBM® SPSS version 25 (SPSS Inc. USA) software was used for analysis. Chi-square and binary logistic regression tests were used to test the association between categorical variables and predictors of adherence to pre-BCG vaccination precautions, respectively, and a p-value of <.05 was considered statistically significant. The AEFIs commonly reported by mothers included abscess, injection site pain, injection site redness, fever, rash, muscle weakness, diarrhea, vomiting, coughing and rhinitis. Ninety-three participants (73.2%) were adherent to pre-BCG vaccination precautions. Ninety-two participants (72.4%) informed mothers to report all AEFIs encountered. Adherence to pre-BCG vaccination precautions and AEFI reporting were generally good; however, there is still room for improvement.

Lower incidence of hospital-treated infections in infants under 3 months of age vaccinated with BCG

BACKGROUND

Live vaccines potentially have non-specific effects that protect against other infections than those the vaccines are targeted against. The national vaccination program (NVP) in Finland was changed on September 1st, 2006: before BCG vaccine was given to all newborn babies and afterwards to babies in risk groups only. We used this natural experiment to study the non-specific effects of BCG in the frame of NVP using before-after design.

METHODS

We compared the incidence of several outcomes obtained from Finnish health registers between children born between July 1st, 2004, and June 30th, 2006 (BCG-eligible) and an age- and season-matched reference cohort born between July 1st, 2007, and June 30th, 2009 (BCG-non-eligible) using Poisson regression. These cohorts were restricted to full-term children whose parents were born in Finland. Follow-up began at birth and lasted 3 months, which is the scheduled age for DTaP-IPV-Hib vaccination, and from 4 months until first birthday. The outcomes included all infections, pneumonia and injuries as a negative control outcome.

RESULTS

The incidence rate ratio (IRR) of the BCG-eligible cohort (N = 93,658) compared to BCG-non-eligible cohort (N = 94,712) for hospital-diagnosed infections was 0.89 (95 %Cl 0.86-0.93) for the 3-month follow-up. The decrease was mainly caused by respiratory infections. In 4-12 months follow-up the BCG-eligible had slightly more infections than BCG-non-eligible children (IRR 1.03, 1.01-1.06).

CONCLUSIONS

BCG vaccination was associated with a lower incidence of all hospital-diagnosed infections during the first three months of life. The difference cannot be attributed to lung tuberculosis, since only few paediatric cases occurred in Finland during 2000s. The disappearance of non-specific effect after administration of an inactivated vaccine is compatible with previous studies.

Evidence-based interventions to reduce mortality among preterm and low-birthweight neonates in low-income and middle-income countries: a systematic review and meta-analysis

Background

Preterm birth is the leading cause of under-five-mortality worldwide, with the highest burden in low-income and middle-income countries (LMICs). The aim of this study was to synthesise evidence-based interventions for preterm and low birthweight (LBW) neonates in LMICs, their associated neonatal mortality rate (NMR), and barriers and facilitators to their implementation. This study updates all existing evidence on this topic and reviews evidence on interventions that have not been previously considered in current WHO recommendations.

Methods

Six electronic databases were searched until 3 March 2020 for randomised controlled trials reporting NMR of preterm and/or LBW newborns following any intervention in LMICs. Risk ratios for mortality outcomes were pooled where appropriate using a random effects model (PROSPERO registration number: CRD42019139267).

Results

1236 studies were identified, of which 49 were narratively synthesised and 9 contributed to the meta-analysis. The studies included 39 interventions in 21 countries with 46 993 participants. High-quality evidence suggested significant reduction of NMR following antenatal corticosteroids (Pakistan risk ratio (RR) 0.89; 95% CI 0.80 to 0.99|Guatemala 0.74; 0.68 to 0.81), single cord (0.65; 0.50 to 0.86) and skin cleansing with chlorhexidine (0.72; 0.55 to 0.95), early BCG vaccine (0.64; 0.48 to 0.86; I² 0%), community kangaroo mother care (OR 0.73; 0.55 to 0.97; I² 0%) and home-based newborn care (preterm 0.25; 0.14 to 0.48|LBW 0.42; 0.27 to 0.65). No effects on perinatal (essential newborn care 1.02; 0.91 to 1.14|neonatal resuscitation 0.95; 0.84 to 1.07) or 7-day NMR (essential newborn care 1.03; 0.83 to 1.27|neonatal resuscitation 0.92; 0.77 to 1.09) were observed after training birth attendants.

Conclusion

The findings of this study encourage the implementation of additional, evidence-based interventions in the current (WHO) guidelines and to be selective in usage of antenatal corticosteroids, to reduce mortality among preterm and LBW neonates in LMICs. Given the global commitment to end all preventable neonatal deaths by 2030, continuous evaluation and improvement of the current guidelines should be a priority on the agenda.

Effects of neonatal nutrition interventions on neonatal mortality and child health and development outcomes: A systematic review

Background

The last two decades have seen a significant decrease in mortality for children <5 years of age in low and middle-income countries (LMICs); however, neonatal (age, 0-28 days) mortality has not decreased at the same rate. We assessed three neonatal nutritional interventions that have the potential of reducing morbidity and mortality during infancy in LMICs.

Objectives

To determine the efficacy and effectiveness of synthetic vitamin A, dextrose oral gel, and probiotic supplementation during the neonatal period.

Search Methods

We conducted electronic searches for relevant studies on the following databases: PubMed, CINAHL, LILACS, SCOPUS, and CENTRAL, Cochrane Central Register for Controlled Trials, up to November 27, 2019.

Selection Criteria

We aimed to include randomized and quasi-experimental studies. The target population was neonates in LMICs. The interventions included synthetic vitamin A supplementation, oral dextrose gel supplementation, and probiotic supplementation during the neonatal period. We included studies from the community and hospital settings irrespective of the gestational age or birth weight of the neonate.

Data Collection and Analysis

Two authors screened the titles and extracted the data from selected studies. The risk of bias (ROB) in the included studies was assessed according to the Cochrane Handbook of Systematic Reviews. The primary outcome was all-cause mortality. The secondary outcomes were neonatal sepsis, necrotizing enterocolitis (NEC), prevention and treatment of neonatal hypoglycaemia, adverse events, and neurodevelopmental outcomes. Data were meta-analyzed by random effect models to obtain relative risk (RR) and 95% confidence interval (CI) for dichotomous outcomes and mean difference with 95% CI for continuous outcomes. The overall rating of evidence was determined by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

Main Results

Sixteen randomized studies (total participants 169,366) assessed the effect of vitamin A supplementation during the neonatal period. All studies were conducted in low- and middle-income (LMIC) countries. Thirteen studies were conducted in the community setting and three studies were conducted in the hospital setting, specifically in neonatal intensive care units. Studies were conducted in 10 different countries including India (four studies), Guinea-Bissau (three studies), Bangladesh (two studies), and one study each in China, Ghana, Indonesia, Nepal, Pakistan, Tanzania, and Zimbabwe. The overall ROB was low in most of the included studies for neonatal vitamin A supplementation. The pooled results from the community based randomized studies showed that there was no significant difference in all-cause mortality in the vitamin A (intervention) group compared to controls at 1 month (RR, 0.99; 95% CI, 0.90-1.08; six studies with 126,548 participants, statistical heterogeneity I 2 0%, funnel plot symmetrical, grade rating high), 6 months (RR, 0.98; 95% CI, 0.89-1.07; 12 studies with 154,940 participants, statistical heterogeneity I 2 43%, funnel plot symmetrical, GRADE quality high) and 12 months of age (RR, 1.04; 95% CI, 0.94-1.14; eight studies with 118,376 participants, statistical heterogeneity I 2 46%, funnel plot symmetrical, GRADE quality high). Neonatal vitamin A supplementation increased the incidence of bulging fontanelle by 53% compared to control (RR, 1.53; 95% CI, 1.12-2.09; six studies with 100,256 participants, statistical heterogeneity I 2 65%, funnel plot symmetrical, GRADE quality high). We did not identify any experimental study that addressed the use of dextrose gel for the prevention and/or treatment of neonatal hypoglycaemia in LMIC. Thirty-three studies assessed the effect of probiotic supplementation during the neonatal period (total participants 11,595; probiotics: 5854 and controls: 5741). All of the included studies were conducted in LMIC and were randomized. Most of the studies were done in the hospital setting and included participants who were preterm (born < 37 weeks gestation) and/or low birth weight (<2500 g birth weight). Studies were conducted in 13 different countries with 10 studies conducted in India, six studies in Turkey, three studies each in China and Iran, two each in Mexico and South Africa, and one each in Bangladesh, Brazil, Colombia, Indonesia, Nepal, Pakistan, and Thailand. Three studies were at high ROB due to lack of appropriate randomization sequence or allocation concealment. Combined data from 25 studies showed that probiotic supplementation reduced all-cause mortality by 20% compared to controls (RR, 0.80; 95% CI, 0.66-0.96; total number of participants 10,998, number needed to treat 100, statistical heterogeneity I 2 0%, funnel plot symmetrical, GRADE quality high). Twenty-nine studies reported the effect of probiotics on the incidence of NEC, and the combined results showed a relative reduction of 54% in the intervention group compared to controls (RR, 0.46; 95% CI, 0.35-0.59; total number of participants 5574, number needed to treat 17, statistical heterogeneity I 2 24%, funnel plot symmetrical, GRADE quality high). Twenty-one studies assessed the effect of probiotic supplementation during the neonatal period on neonatal sepsis, and the combined results showed a relative reduction of 22% in the intervention group compared to controls (RR, 0.78; 95% CI, 0.70-0.86; total number of participants 9105, number needed to treat 14, statistical heterogeneity I 2 23%, funnel plot symmetrical, GRADE quality high).

Authors' Conclusions

Vitamin A supplementation during the neonatal period does not reduce all-cause neonatal or infant mortality in LMICs in the community setting. However, neonatal vitamin A supplementation increases the risk of Bulging Fontanelle. No experimental or quasi-experimental studies were available from LMICs to assess the effect of dextrose gel supplementation for the prevention or treatment of neonatal hypoglycaemia. Probiotic supplementation during the neonatal period seems to reduce all-cause mortality, NEC, and sepsis in babies born with low birth weight and/or preterm in the hospital setting. There was clinical heterogeneity in the use of probiotics, and we could not recommend any single strain of probiotics for wider use based on these results. There was a lack of studies on probiotic supplementation in the community setting. More research is needed to assess the effect of probiotics administered to neonates in-home/community setting in LMICs.

Bacillus Calmette-Guérin vaccination at birth: Effects on infant growth. A randomized clinical trial

BACKGROUND

Bacillus Calmette-Guérin vaccine (BCG) induces a complex, pro-inflammatory immune response. Obesity is associated with low-grade inflammation.

AIMS

The purpose of the study was to test whether BCG at birth has effects on infant growth and body composition.

STUDY DESIGN, SUBJECTS, AND OUTCOME MEASURES

The Danish Calmette Study is a randomized, clinical trial. The study was conducted at three university hospitals and randomized 4262 children of gestational age ≥32weeks to receive BCG within seven days of birth or to a no-intervention control group. Follow-up consisted of clinical examinations. Outcome measures were weight and length at 3months, and weight, length, mid upper-arm circumference, and triceps and subscapular skinfold at 13months. Data collectors were blinded to allocation. Anthropometric measurements were converted to z-scores using WHO reference population.

RESULTS

Follow-up was 94% complete at 3 and 13months after birth. The children were bigger than the WHO reference population. There was no effect of BCG on weight z-score at 13months (-0.028 [95% confidence interval: -0.085 to 0.029], p=0.34). There was no effect on weight and length at 3months, or length, mid-upper-arm circumference, or triceps and subscapular skinfold at 13months.

CONCLUSION

In this study, vaccination with BCG at birth did not have effects on child growth or body composition at 13months.

TRIAL REGISTRATION

www.clinicaltrials.gov, registration number NCT01694108.

Human biomarkers: can they help us to develop a new tuberculosis vaccine?

The most effective intervention for the control of infectious disease is vaccination. The BCG vaccine, the only licensed vaccine for the prevention of tuberculosis (TB) disease, is only partially effective and a new vaccine is urgently needed. Biomarkers can aid the development of new TB vaccines through discovery of immune mechanisms, early assessment of vaccine immunogenicity or vaccine take and identification of those at greatest risk of disease progression for recruitment into smaller, targeted efficacy trials. The ultimate goal, however, remains a biomarker of TB vaccine efficacy that can be used as a surrogate for a TB disease end point and there remains an urgent need for further research in this area.