Randomized trial of BCG in healthcare workers to reduce absenteeism during the COVID-19 pandemic in sub-Saharan Africa.

Background: We tested whether providing BCG vaccine to healthcare workers (HCWs) could reduce non-planned absenteeism and thereby reduce the potential impact of the COVID-19 pandemic on healthcare systems in Africa.

Methods: We conducted a multicenter, single-blinded, placebo-controlled randomized trial in Guinea-Bissau and Mozambique between December 2020 and June 2022. Participants were randomized 1:1 to BCG vaccine or placebo (saline) and followed by biweekly telephone calls for 6 mo.

Evaluating the effect of BCG vaccination for non-specific protection from infection in senior citizens during the COVID-19 pandemic: A randomised clinical trial.

Objectives: The Bacillus Calmette-Guérin (BCG) vaccine may induce non-specific protection against unrelated infections. We tested the effect of BCG on the risk of infections among Danish senior citizens.

Methods: Single-blinded randomised controlled trial including 1676 volunteers >65 years.

Maternal Bacille Calmette-Guérin Scars and Mortality Risk for Male and Female Newborns: Observational Study From Guinea-Bissau.

Background: Maternal priming with bacille Calmette-Guérin (BCG) has been associated with reduced mortality in male offspring. We investigated this association in a cohort of healthy BCG-vaccinated neonates.

Methods: This observational study within a randomized controlled trial comparing different BCG strains was conducted in Guinea-Bissau from 2017 to 2020.

Effects of Neonatal BCG-Japan Versus BCG-Russia Vaccination on Overall Mortality and Morbidity: Randomized Controlled Trial From Guinea-Bissau (BCGSTRAIN II).

Background: Vaccination with the Danish strain of bacille Calmette-Guérin (BCG) has been associated with pronounced reductions in all-cause neonatal mortality and morbidity. Developing a skin reaction postvaccination is associated with markedly reduced mortality risk. It is unknown whether the beneficial nonspecific effects are maintained across different BCG strains.

The association between BCG scars and self-reported chronic diseases: A cross-sectional observational study within an RCT of Danish health care workers.

Introduction: The live-attenuated vaccines Bacillus Calmette-Guérin (BCG) and Vaccinia have been associated with beneficial non-specific effects. We assessed the prevalence of BCG and Vaccinia vaccine scars in a cohort of Danish health care workers and investigated the association between the presence of vaccine scars and self-reported chronic diseases.

Methods: Cross-sectional study utilizing baseline data collected during 2020-2021 at enrollment in a BCG trial aiming to assess the effect of BCG vaccination on absenteeism and infectious disease morbidity during the SARS-COV-2 pandemic.

Nonspecific Effects of the Bacillus Calmette-Guérin Vaccine in Portuguese Children Under 5 Years of Age: Protocol for a Population-Based Historical Birth Cohort Study.

Background: The Bacillus Calmette-Guérin vaccine (BCG) against tuberculosis (TB) shows beneficial nonspecific effects, which are likely related to innate immune training. Until 2016, a single BCG dose was administered to all newborns in Portugal. In July 2016, a clinical guideline established that only children under 6 years belonging to high-risk groups should receive BCG.

Using BCG Vaccine to Enhance Nonspecific Protection of Health Care Workers During the COVID-19 Pandemic: A Randomized Controlled Trial.

Background: The BCG (Bacillus Calmette-Guérin) vaccine can induce nonspecific protection against unrelated infections. We aimed to test the effect of BCG on absenteeism and health of Danish health care workers (HCWs) during the coronavirus disease 2019 (COVID-19) pandemic.

Methods: A single-blinded randomized controlled trial included 1221 HCWs from 9 Danish hospitals.

Policies on children and schools during the SARS-CoV-2 pandemic in Western Europe.

During the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mitigation policies for children have been a topic of considerable uncertainty and debate. Although some children have co-morbidities which increase their risk for severe coronavirus disease (COVID-19), and complications such as multisystem inflammatory syndrome and long COVID, most children only get mild COVID-19. On the other hand, consistent evidence shows that mass mitigation measures had enormous adverse impacts on children.

Using real-life data to model the impact of increasing BCG vaccination coverage and scar prevalence on all-cause infant mortality.

Purpose: Estimating the potential impact on infant mortality of increasing Bacille Calmette-Guérin (BCG) vaccination coverage and BCG scar prevalence.

Methods: Guinea-Bissau Health and Demographic Surveillance System data on BCG vaccination coverage, scar status, and all-cause mortality were used for this study. Mortality risk (MR) by scar status was assessed in Cox models providing adjusted mortality rate ratios (aMRRs).

Randomized clinical trials of COVID-19 vaccines: Do adenovirus-vector vaccines have beneficial non-specific effects?

We examined the possible non-specific effects of novel mRNA- and adenovirus-vector COVID-19 vaccines by reviewing the randomized control trials (RCTs) of mRNA and adenovirus-vector COVID-19 vaccines. We calculated mortality risk ratios (RRs) for mRNA COVID-19 vaccines vs. placebo recipients and compared them with the RR for adenovirus-vector COVID-19 vaccine recipients vs.

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.

Mortality Risk Among Frail Neonates and Maternal BCG Vaccine Scar Status: Observational Study From Guinea-Bissau.

Background: Maternal priming with the Bacille Calmette-Guérin (BCG) vaccine has been associated with reduced offspring mortality rates. We investigated this association in a cohort of frail neonates.

Methods: We performed an observational study within a randomized BCG trial conducted at the neonatal intensive care unit (NICU) in Guinea-Bissau from 2015 to 2017.

The association between parental and neonatal BCG vaccination and neonatal T helper 17 cell expansion.

Background: Bacille Calmette-Guérin (BCG) vaccination reduces the severity of neonatal infections; this effect appears enhanced if the mother has received BCG. We performed immunophenotyping of the T-cell subset and characterized T-cell proliferation responses to assess possible immune response pathways.

Methods: Healthy BCG-vaccinated (n = 8) and unvaccinated (n = 9) neonates born by elective caesarean section were sampled 3 weeks after birth.

SARS-CoV-2 serosurvey among adults involved in healthcare and health research in Guinea-Bissau, West Africa.

Objectives: Many African countries have reported fewer COVID-19 cases than countries elsewhere. By the end of 2020, Guinea-Bissau, West Africa, had <2500 PCR-confirmed cases corresponding to 0.1% of the ∼1.

Maternal BCG primes for enhanced health benefits in the newborn.

Objectives: Bacille Calmette-Guérin (BCG) vaccination lowers the risk of severe infection; we tested whether effects are modulated by maternal BCG in a large cohort of BCG-vaccinated newborns from Guinea-Bissau.

Methods: Maternal BCG scar status were inspected at enrolment in a BCG trial conducted from 2014 to 17 in Bissau, Guinea-Bissau. We tested associations with background factors for potential confounding; maternal age affected effect estimates >5% and accordingly, all analyses were adjusted for maternal age.

Reactivation of BCG vaccination scars after vaccination with mRNA-Covid-vaccines: two case reports.

Background: From May 2020 to January 2021, we enrolled 1233 health care workers (HCW) from Danish Hospitals in a randomized trial evaluating whether Bacille Calmette-Guérin (BCG) provides protection against COVID-19. Participants were randomized 1:1 to BCG vs saline and followed for 6 months. From December 2020, Covid-19 vaccines were offered to the HCW.

Parental Bacillus Calmette-Guérin vaccine scars decrease infant mortality in the first six weeks of life: A retrospective cohort study.

Background: Live attenuated vaccines have been observed to have particularly beneficial effects for child survival when given in the presence of maternally transferred immunity (priming). We aimed to test this finding and furthermore explore the role of paternal priming.

Methods: In an exploratory, retrospective cohort study in 2017, parental Bacillus Calmette-Guérin (BCG) scars were assessed for infants from the Bandim Health Project (BHP) who had participated in a 2008-2013 trial of neonatal BCG vaccination.

Neonatal Bacille Calmette-Guérin vaccination and tuberculin skin test reactions at 2- and 6-months: Effects on mortality up to 1 year of age.

Background: In randomized trials, Bacille Calmette-Guérin (BCG) vaccine has been associated with reduced all-cause mortality. BCG-induced Tuberculin Skin Test (TST) reactions have also been associated with reduced all-cause mortality. We aimed to assess the association between TST responses and subsequent mortality in three birth cohorts and conducted a meta-analysis of existing studies.

Retesting the hypothesis that early Diphtheria-Tetanus-Pertussis vaccination increases female mortality: An observational study within a randomised trial.

Background: There are worrying indications that diphtheria-tetanus-pertussis (DTP) vaccine has negative non-specific effects for females. We previously found, in a trial of early-Bacillus Calmette-Guérin (BCG) to low weight (LW) neonates, that receiving early-DTP (before 2 months of age), was associated with increased female mortality compared with no-DTP/delayed-DTP. Within a subsequent LW trial, we aimed to retest this observation.

The introduction of BCG vaccination to neonates in Northern Sweden, 1927-31: Re-analysis of historical data to understand the lower mortality among BCG-vaccinated children.

Background: Following the introduction of oral Bacille Calmette-Guérin (BCG) a century ago, Albert Calmette suggested that BCG both provided protection against death from tuberculosis (TB) and other causes. The findings were not pursued. Today, there is considerable evidence that intradermal BCG have beneficial non-specific effects (NSEs).