Neonatal BCG Vaccination for Prevention of Allergy in Infants: The MIS BAIR Randomised Controlled Trial.

BACKGROUND: The beneficial off-target effects of Bacille Calmette-Guérin (BCG) vaccination potentially include protection against allergy. OBJECTIVE: In the MIS BAIR trial, we aimed to determine whether neonatal BCG vaccination reduces atopic sensitisation and clinical food allergy in infants. METHODS: In this randomised controlled trial, 1272 neonates were allocated to BCG-Denmark vaccine (0.05 mL intradermal dose) or no BCG at birth. Randomisation was stratified by recruitment site, mode of delivery and plurality of birth. The primary outcome was the incidence of atopic sensitisation determined by skin prick test at 1 year of age. Food allergy was determined by 3-monthly online questionnaires and oral food challenges. Data were analysed by intention-to-treat using binary regression. CLINICALTRIALS: gov (NCT01906853). RESULTS: Atopic sensitisation during the first year of life was 22.9% among infants in the BCG group and 18.9% in the control group (adjusted risk difference (aRD) 3.8% (95% CI -1.5 to 9.1) after multiple imputation). Clinical food allergy was similar between infants in the BCG and control groups (9.8% vs. 9.6%; aRD 0.2, 95% CI -3.4 to 3.8). An interaction was observed between the primary outcome and maternal history of BCG vaccination. No interaction was observed for the additional prespecified potential effect modifiers tested (sex, delivery mode, family history of any allergy, season of birth, hepatitis B vaccination at randomisation, BCG scar and age at BCG administration). CONCLUSIONS AND CLINICAL RELEVANCE: Neonatal BCG-Denmark vaccination does not protect against atopic sensitisation or clinical food allergy in the first year of life.

Implications of Non-Specific Effects for Testing, Approving, and Regulating Vaccines.

The current framework for testing and regulating vaccines was established before the realization that vaccines, in addition to their effect against the vaccine-specific disease, may also have "non-specific effects" affecting the risk of unrelated diseases. Accumulating evidence from epidemiological studies shows that vaccines in some situations can affect all-cause mortality and morbidity in ways that are not explained by the prevention of the vaccine-targeted disease. Live attenuated vaccines have sometimes been associated with decreases in mortality and morbidity that are greater than anticipated. In contrast, some non-live vaccines have in certain contexts been associated with increases in all-cause mortality and morbidity. The non-specific effects are often greater for female than male individuals. Immunological studies have provided several mechanisms that explain how vaccines might modulate the immune response to unrelated pathogens, such as through trained innate immunity, emergency granulopoiesis, and heterologous T-cell immunity. These insights suggest that the framework for the testing, approving, and regulating vaccines needs to be updated to accommodate non-specific effects. Currently, non-specific effects are not routinely captured in phase I-III clinical trials or in the post-licensure safety surveillance. For instance, an infection with Streptococcus pneumoniae occurring months after a diphtheria-tetanus-pertussis vaccination would not be considered an effect of the vaccination, although evidence indicates it might well be for female individuals. Here, as a starting point for discussion, we propose a new framework that considers the non-specific effects of vaccines in both phase III trials and post-licensure.

Association Between Centralization and Outcome for Children Admitted to Intensive Care in Australia and New Zealand: A Population-Based Cohort Study.

OBJECTIVES: To describe regional differences and change over time in the degree of centralization of pediatric intensive care in Australia and New Zealand (ANZ) and to compare the characteristics and ICU mortality of children admitted to specialist PICUs and general ICUs (GICUs). DESIGN: A retrospective cohort study using registry data for two epochs of ICU admissions, 2003-2005 and 2016-2018. SETTING: Population-based study in ANZ. PATIENTS: A total of 43,256 admissions of children aged younger than 16 years admitted to an ICU in ANZ were included. Infants aged younger than 28 days without cardiac conditions were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was risk-adjusted ICU mortality. Logistic regression was used to investigate the association of mortality with the exposure to ICU type, epoch, and their interaction. Compared with children admitted to GICUs, children admitted to PICUs were younger (median 25 vs 47 mo; p < 0.01) and stayed longer in ICU (median 1.6 vs 1.0 d; p < 0.01). For the study overall, 93% of admissions in Australia were to PICUs whereas in New Zealand only 63% of admissions were to PICUs. The adjusted odds of death in epoch 2 relative to epoch 1 decreased (adjusted odds ratio [AOR], 0.50; 95% CI, 0.42-0.59). There was an interaction between unit type and epoch with increased odds of death associated with care in a GICU in epoch 2 (AOR, 1.63; 95% CI, 1.05-2.53 for all admissions; 1.73, CI, 1.002-3.00 for high-risk admissions). CONCLUSIONS: Risk-adjusted mortality of children admitted to specialist PICUs decreased over a study period of 14 years; however, a similar association between time and outcome was not observed in high-risk children admitted to GICUs. The results support the continued use of a centralized model of delivering intensive care for critically ill children.

Discordance Between Diagnosis Tools for Assessing Eczema in Infants: A Challenge for Intervention Trials.

BACKGROUND: There is no standardized definition for infant eczema, and various tools have been used across studies, precluding direct comparison. OBJECTIVE: The aim of the study was to assess and to compare the accuracy of diagnostic tools for infant eczema using the extensive data collected in Melbourne Infant Study: BCG for Allergy and Infection Reduction (MIS BAIR), an eczema prevention trial. METHODS: Eczema incidence was assessed by 3 questionnaire-based measures: modified UK diagnostic tool, parent-reported medically diagnosed eczema, and parent-reported use of topical corticosteroids. Agreement between the definitions was quantified using κ coefficient. Eczema severity was assessed by 3-monthly Patient-Oriented Eczema Measure (POEM) scores and a SCORing Atopic Dermatitis (SCORAD) clinical assessment at a 12-month visit (ClinicalTrial.gov: NCT01906853). RESULTS: Among the 538 participants fulfilling at least 1 of the 3 questionnaire-based eczema definitions, only 197 participants (37%) met all 3 definitions. Agreement between the definitions was poor with κ coefficients ranging from -0.11 to 0.62. The most frequently reported symptoms were generally dry skin (483/538, 90%) and pruritus (400/538, 74%). The face (352/538, 65%) and the trunk (306/538, 57%) were more frequently affected than the creases (257/538, 48%). Participants fulfilling all 3 questionnaire-based definitions of eczema were more likely to have higher severity scores and earlier onset of symptoms. CONCLUSIONS: There is poor agreement between currently available tools for assessing infant eczema.

Pragmatic Randomized Trial of Corticosteroids and Inhaled Epinephrine for Bronchiolitis in Children in Intensive Care.

OBJECTIVE: To determine whether the combination of systemic corticosteroids and nebulized epinephrine, compared with standard care, reduces the duration of positive pressure support in children with bronchiolitis admitted to intensive care. STUDY DESIGN: We performed a pragmatic, multicenter, open-label, randomized trial between July 2013 and November 2019 in children younger than 18 months old with a clinical diagnosis of bronchiolitis. The intervention group received the equivalent of 13 mg/kg prednisolone over 3 days, then 1 mg/kg daily for 3 days, plus 0.05 mL/kg of nebulized 1% epinephrine made up to 6 ml with 0.9% saline via jet nebulizer and mask using oxygen at 12 l/min every 30 minutes for 5 doses, then 1-4 hourly for 3 days, then as required for 3 days. The primary outcome was clinician-managed duration of positive pressure support in intensive care defined as high-flow nasal-prong oxygen, nasopharyngeal continuous positive airway pressure, or mechanical ventilation. RESULTS: In total, 210 children received positive pressure support. In the corticosteroid-epinephrine group, 107 children received positive pressure support for a geometric mean of 26 (95% CI, 22-32) hours compared with 40 (95% CI 34-47) hours in 103 controls, adjusted ratio 0.66 (95% CI 0.51-0.84), P = .001. In the intervention group, 41 (38%) children experienced at least 1 adverse event, compared with 39 (38%) in the control group. CONCLUSIONS: In children with severe bronchiolitis, the duration of clinician-managed pressure support was reduced by regular treatment with systemic corticosteroids and inhaled epinephrine compared with standard care. CLINICAL TRIAL REGISTRATION: Australian Clinical Trials Research Network: ACTRN12613000316707.

Prevention of infant eczema by neonatal Bacillus Calmette-Guérin vaccination: The MIS BAIR randomized controlled trial.

BACKGROUND: Bacille Calmette-Guérin (BCG) vaccine could play a role in counteracting the rising prevalence of atopic diseases, through its beneficial off-target effects. We aimed to determine whether neonatal BCG vaccination reduces the incidence of eczema in infants. METHODS: Randomized controlled trial with 1272 infants allocated to receive BCG-Denmark or no BCG at birth. The primary outcome was the 12-month incidence of eczema based on 3-monthly questionnaires. Eczema was also assessed at a 12-month clinic visit. ClinicalTrial.gov: NCT01906853. RESULTS: The 12-month eczema incidence was 32.2% in the BCG group compared with 36.6% in the control group (adjusted risk difference (aRD) -4.3%, 95% CI -9.9% to 1.3%, multiple imputation model). In addition, comparing infants in the BCG group with the control group, 15.7% vs. 19.2% had eczema lesions at the 12-month visit (aRD -3.5%, 95% CI -8.0% to 1.0%); 35.7% vs. 39.0% reported using topical steroids (aRD -3.3, 95% CI -9.2 to 2.7); and 7.3% vs. 10.2% had severe eczema scores (aRD -3.0%, 95% CI -8.8% to 2.7%). In 344 high-risk infants (two atopic parents), the 12-month eczema incidence was 35.3% in the BCG group compared with 46.8% in the control group (aRD -11.5%, 95% CI -21.9% to -1.2%; number needed to treat 8.7, 95% CI 4.6 to 83.3). CONCLUSION: There is insufficient evidence to recommend neonatal BCG vaccination in all infants for the prevention of eczema in the first year of life; however, a modest beneficial effect was observed among high-risk infants. A single dose of BCG-Denmark soon after birth could reduce the incidence of eczema in infants with two atopic parents.

BCG vaccination to reduce the impact of COVID-19 in healthcare workers: Protocol for a randomised controlled trial (BRACE trial).

INTRODUCTION: BCG vaccination modulates immune responses to unrelated pathogens. This off-target effect could reduce the impact of emerging pathogens. As a readily available, inexpensive intervention that has a well-established safety profile, BCG is a good candidate for protecting healthcare workers (HCWs) and other vulnerable groups against COVID-19. METHODS AND ANALYSIS: This international multicentre phase III randomised controlled trial aims to determine if BCG vaccination reduces the incidence of symptomatic and severe COVID-19 at 6 months (co-primary outcomes) compared with no BCG vaccination. We plan to randomise 10 078 HCWs from Australia, The Netherlands, Spain, the UK and Brazil in a 1:1 ratio to BCG vaccination or no BCG (control group). The participants will be followed for 1 year with questionnaires and collection of blood samples. For any episode of illness, clinical details will be collected daily, and the participant will be tested for SARS-CoV-2 infection. The secondary objectives are to determine if BCG vaccination reduces the rate, incidence, and severity of any febrile or respiratory illness (including SARS-CoV-2), as well as work absenteeism. The safety of BCG vaccination in HCWs will also be evaluated. Immunological analyses will assess changes in the immune system following vaccination, and identify factors associated with susceptibility to or protection against SARS-CoV-2 and other infections. ETHICS AND DISSEMINATION: Ethical and governance approval will be obtained from participating sites. Results will be published in peer-reviewed open-access journals. The final cleaned and locked database will be deposited in a data sharing repository archiving system. TRIAL REGISTRATION: ClinicalTrials.gov NCT04327206.

Neonatal Bacille Calmette-Guérin Vaccination and Infections in the First Year of Life: The MIS BAIR Randomized Controlled Trial.

BACKGROUND: Bacille Calmette-Guérin (BCG) vaccination has beneficial off-target effects that may include protecting against non-mycobacterial infectious diseases. We aimed to determine whether neonatal BCG vaccination reduces lower respiratory tract infections (LRTI) in infants in the Melbourne Infant Study: BCG for Allergy and Infection Reduction (MIS BAIR) trial. METHODS: In this investigator-blinded trial, neonates in Australia were randomized to receive BCG-Denmark vaccination or no BCG at birth. Episodes of LRTI were determined by symptoms reported in parent-completed, 3-month questionnaires over the first year of life. Data were analyzed by intention-to-treat using binary regression. RESULTS: A total of 1272 neonates were randomized to the BCG vaccination (n = 637) or control (n = 635) group. The proportion of participants with an episode of LRTI in the first year of life among BCG-vaccinated infants was 54.8% compared to 58.0% in the control group, resulting in a risk difference of -3.2 (95% confidence interval, -9.0 to 2.6) after multiple imputation. There was no interaction observed between the primary outcome and sex, maternal BCG, or the other prespecified effect modifiers. CONCLUSIONS: Based on the findings of this trial, there is insufficient evidence to support the use of neonatal BCG vaccination to prevent LRTI in the first year of life in high-income settings.

Hospital-acquired complications in critically ill patients.

Background: The national hospital-acquired complications (HAC) system has been promoted as a method to identify health care errors that may be mitigated by clinical interventions. Objectives: To quantify the rate of HAC in multiday stay adults admitted to major hospitals. Design: Retrospective observational analysis of 5-year (July 2014 - June 2019) administrative dataset abstracted from medical records. Setting: All 47 hospitals with on-site intensive care units (ICUs) in the State of Victoria. Participants: All adults (aged ≥ 18 years) stratified into planned or unplanned, surgical or medical, ICU or other ward, and by hospital peer group (tertiary referral, metropolitan, regional). Main outcome measures: HAC rates in ICU compared with ward, and mixed-effects regression estimates of the association between HAC and i) risk of clinical deterioration, and ii) admission hospital site (intraclass correlation coefficient [ICC] > 0.3). Results: 211 120 adult ICU separations with mean hospital mortality of 7.3% (95% CI, 7.2-7.4%) reported 110 132 (42.6%) HAC events (commonly, delirium, infection, arrhythmia and respiratory failure) in 62 945 records (29.8%). Higher HAC rates were reported in elective (cardiac [50.3%] and non-cardiac [40.6%]) surgical subgroups compared with emergency medical subgroup (23.9%), and in tertiary (35.4%) compared with non-tertiary (22.7%) hospitals. HAC was strongly associated with on-admission patient characteristics (P < 0.001), but was weakly associated with hospital site (ICC, 0.08; 95% CI, 0.05-0.11). Conclusions: Critically ill patients have a high burden of HAC events, which appear to be associated with patient admission characteristics. HAC may an indicator of hospital admission complexity rather than hospital-acquired complications.

The non-specific and sex-differential effects of vaccines.

The textbook view of vaccination is that it functions to induce immune memory of the specific pathogen components of the vaccine, leading to a quantitatively and qualitatively better response if the host is exposed to infection with the same pathogen. However, evidence accumulated over the past few decades increasingly suggests that vaccines can also have non-specific effects on unrelated infections and diseases, with important implications for childhood mortality particularly in low-income settings. Furthermore, many of these non-specific effects, as well as the pathogen-specific effects, of vaccines show differences between the sexes. Here, members of the Optimmunize consortium discuss the evidence for and potential mechanisms of non-specific and sex-differential effects of vaccines, as well as their potential policy implications. Given that the non-specific effects of some vaccines are now being tested for their ability to protect against COVID-19, the authors also comment on the broader implications of these trials.

BCG vaccination-induced emergency granulopoiesis provides rapid protection from neonatal sepsis.

Death from sepsis in the neonatal period remains a serious threat for millions. Within 3 days of administration, bacille Calmette-Guérin (BCG) vaccination can reduce mortality from neonatal sepsis in human newborns, but the underlying mechanism for this rapid protection is unknown. We found that BCG was also protective in a mouse model of neonatal polymicrobial sepsis, where it induced granulocyte colony-stimulating factor (G-CSF) within hours of administration. This was necessary and sufficient to drive emergency granulopoiesis (EG), resulting in a marked increase in neutrophils. This increase in neutrophils was directly and quantitatively responsible for protection from sepsis. Rapid induction of EG after BCG administration also occurred in three independent cohorts of human neonates.

Licensed Bacille Calmette-Guérin (BCG) formulations differ markedly in bacterial viability, RNA content and innate immune activation.

BACKGROUND: Bacille Calmette-Guérin (BCG), the live attenuated tuberculosis vaccine, is manufactured under different conditions across the globe generating formulations that may differ in clinical efficacy. Innate immune recognition of live BCG contributes to immunogenicity suggesting that differences in BCG viability may contribute to divergent activity of licensed formulations. METHODS: We compared BCG-Denmark (DEN), -Japan (JPN), -India (IND), -Bulgaria (BUL) and -USA in vitro with respect to a) viability as measured by colony-forming units (CFU), mycobacterial membrane integrity, and RNA content, and b) cytokine/chemokine production in newborn cord and adult peripheral blood. RESULTS: Upon culture, relative growth was BCG-USA > JPN â‰« DEN > BUL = IND. BCG-IND and -BUL demonstrated >1000-fold lower growth than BCG-JPN in 7H9 medium and >10-fold lower growth in commercial Middlebrook 7H11 medium. BCG-IND demonstrated significantly decreased membrane integrity, lower RNA content, and weaker IFN-γ inducing activity in whole blood compared to other BCGs. BCG-induced whole blood cytokines differed significantly by age, vaccine formulation and concentration. BCG-induced cytokine production correlated with CFU, suggesting that mycobacterial viability may contribute to BCG-induced immune responses. CONCLUSIONS: Licensed BCG vaccines differ markedly in their content of viable mycobacteria possibly contributing to formulation-dependent activation of innate and adaptive immunity and distinct protective effects.

Study protocol for the Melbourne Infant Study: BCG for Allergy and Infection Reduction (MIS BAIR), a randomised controlled trial to determine the non-specific effects of neonatal BCG vaccination in a low-mortality setting.

INTRODUCTION: BCG vaccination reduces all-cause infant mortality in high-mortality settings by more than can be attributed to protection against tuberculosis. This is proposed to result from non-specific protection against non-vaccine targeted ('off-target') infections. There is also evidence that BCG protects against allergic diseases. METHODS AND ANALYSIS: The Melbourne Infant Study: BCG for Allergy and Infection Reduction is a phase III multicentre, single-blinded, randomised controlled trial. A total of 1438 healthy neonates will be randomised to receive either BCG vaccination or no BCG vaccination in the first 10 days of life. Measures of allergy, eczema, infection and asthma will be obtained from parent-completed questionnaires 3 monthly in the first year and 6 monthly from 1 to 5 years of age, and clinical assessments at 1 and 5 years of age. Biological samples will also be collected for future immunological studies. ANALYSIS PRIMARY OUTCOME: The proportion of participants with measures of allergy and infection (atopic sensitisation, eczema, lower respiratory tract infection) at 1 and 5 years of age, and asthma at 5 years of age. SECONDARY OUTCOMES: (1) the proportion of participants with additional measures of allergy, eczema, asthma and infections; (2) medication use for eczema and asthma; (3) the severity and age of onset of eczema and asthma; (4) the number of episodes of infection; (5) hospitalisations for infections and (6) laboratory measures of immune responses. ETHICS AND DISSEMINATION: This trial has ethical and governance approval from Mercy Health Human Research Ethics Committee (HREC, No. R12-28) and Royal Children's Hospital HREC (No. 33025) with additional governance approval from Barwon Health and St John of God, Geelong, Victoria. Results of this trial will be published in peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION NUMBER: NCT01906853.

RACHS - ANZ : A Modified Risk Adjustment in Congenital Heart Surgery Model for Outcome Surveillance in Australia and New Zealand.

Background Outcomes for pediatric cardiac surgery are commonly reported from international databases compiled from voluntary data submissions. Surgical outcomes for all children in a country or region are less commonly reported. We aimed to describe the bi-national population-based outcome for children undergoing cardiac surgery in Australia and New Zealand and determine whether the Risk Adjustment for Congenital Heart Surgery ( RACHS ) classification could be used to create a model that accurately predicts in-hospital mortality in this population. Methods and Results The study was conducted in all children's hospitals performing cardiac surgery in Australia and New Zealand between January 2007 and December 2015. The performance of the original RACHS -1 model was assessed and compared with an alternative RACHS - ANZ (Australia and New Zealand) model, developed balancing discrimination with parsimonious variable selection. A total of 14 324 hospital admissions were analyzed. The overall hospital mortality was 2.3%, ranging from 0.5% for RACHS category 1 procedures, to 17.0% for RACHS category 5 or 6 procedures. The original RACHS -1 model was poorly calibrated with death overpredicted (1161 deaths predicted, 289 deaths observed). The RACHS - ANZ model had better performance in this population with excellent discrimination (Az- ROC of 0.830) and acceptable Hosmer and Lemeshow goodness-of-fit ( P=0.216). Conclusions The original RACHS -1 model overpredicts mortality in children undergoing heart surgery in the current era. The RACHS - ANZ model requires only 3 risk variables in addition to the RACHS procedure category, can be applied to a wider range of patients than RACHS -1, and is suitable to use to monitor regional pediatric cardiac surgery outcomes.

Two Randomized Trials of the Effect of the Russian Strain of Bacillus Calmette-Guérin Alone or With Oral Polio Vaccine on Neonatal Mortality in Infants Weighing <2000 g in India.

BACKGROUND: In randomized trials in Guinea-Bissau, the Danish strain of Bacillus Calmette-Guérin (BCG) reduces neonatal mortality, primarily by reducing deaths from pneumonia and sepsis. Because World Health Organization-prequalified BCG-Denmark was not available in India, we conducted 2 randomized trials to test whether BCG-Russia alone or with oral polio vaccine (OPV) has similar effects to BCG-Denmark. METHODS: We randomized neonates weighing <2000 g to a control group that was not vaccinated before 28 days of age or to receive either BCG-Russia alone (first trial) or BCG-Russia with OPV (second trial) soon after birth. We performed intention-to-treat analysis using Cox hazards models with age as the underlying time and adjusted for weight, sex and inborn versus outborn status. RESULTS: Administration of BCG-Russia alone had no effect on neonatal mortality (to 28 days of age): 15.6% of 1537 infants died in the BCG-Russia group and 16.1% of 1535 died in the control group; the adjusted hazard ratio was 0.95 [95% confidence interval (CI): 0.80-1.13]. Administration of BCG-Russia with OPV also had no effect on neonatal mortality: 18.0% of 1103 infants died in the BCG-OPV group and 17.6% of 1104 died in the control group; the adjusted hazard ratio was 1.01 (95% CI: 0.83-1.23). The adjusted hazard ratio for the 2 trials combined was 0.98 (95% CI: 0.85-1.11). CONCLUSIONS: BCG-Russia with or without OPV had no effect on neonatal mortality. It is important to determine which strains of BCG have the greatest specific effects (on tuberculosis) and nonspecific effects (on infections other than tuberculosis) in high-mortality regions.

Long-Term Effects of Saline Instilled During Endotracheal Suction in Pediatric Intensive Care: A Randomized Trial.

BACKGROUND: Saline instillation is still used to assist in removal of secretions from endotracheal tubes in some pediatric intensive care units. OBJECTIVE: To compare the effect of using either no saline, quarter-normal (0.225%) saline, or normal (0.9%) saline during endotracheal suctioning of children receiving ventilatory support in a pediatric intensive care unit. METHOD: An unblinded, randomized trial with 3 treatment groups was conducted with 427 children who received ventilatory support for at least 12 hours. Children were randomly assigned to receive no saline, 0.225% saline, or 0.9% saline during routine endotracheal suctioning. RESULTS: The primary outcome was the number of hours of invasive mechanical ventilation; oxygen therapy and length of stay in the unit were secondary outcomes. There were 138 children randomly assigned to the no-saline group, 141 to the 0.225% saline group, and 148 to the 0.9% saline group. In Kaplan-Meier intention-to-treat analysis, the median (interquartile range) number of hours of invasive mechanical ventilation was 32 (20-68), 43 (21-86), and 40 (20-87) in the no-saline, 0.225% saline, and 0.9% saline groups, respectively. Although the no-saline group received fewer hours of invasive ventilation, oxygen therapy, and intensive care than the other groups combined, the differences were not statistically significant. CONCLUSION: Using no saline was at least as effective as using either 0.225% or 0.9% saline in endotracheal suctioning. The optimal policy may be to routinely use no saline with endotracheal suctioning in children but allow the occasional use of 0.9% saline when secretions are thick.