Effect of distributing locally produced cloth facemasks on COVID-19-like illness and all-cause mortality-a cluster-randomised controlled trial in urban Guinea-Bissau.

Facemasks have been employed to mitigate the spread of SARS-CoV-2. The community effect of providing cloth facemasks on COVID-19 morbidity and mortality is unknown. In a cluster randomised trial in urban Bissau, Guinea-Bissau, clusters (geographical areas with an average of 19 houses), were randomised to an intervention or control arm using computer-generated random numbers.

Stopping Oral Polio Vaccine (OPV) After Defeating Poliomyelitis in Low- and Middle-Income Countries: Harmful Unintended Consequences? Review of the Nonspecific Effects of OPV.

Background: The live vaccines bacille Calmette-Guérin (BCG) and measles vaccine have beneficial nonspecific effects (NSEs) reducing mortality, more than can be explained by prevention of tuberculosis or measles infection. Live oral polio vaccine (OPV) will be stopped after polio eradication; we therefore reviewed the potential NSEs of OPV.

Methods: OPV has been provided in 3 contexts: (1) coadministration of OPV and diphtheria-tetanus-pertussis (DTP) vaccine at 6, 10, and 14 weeks of age; (2) at birth (OPV0) with BCG; and (3) in OPV campaigns (C-OPVs) initiated to eradicate polio infection.

Understanding the child mortality decline in Guinea-Bissau: the role of population-level nutritional status measured by mid-upper arm circumference.

Background: Malnutrition is considered an important contributing factor to child mortality, and the mid-upper arm circumference (MUAC) is regarded as one of the better anthropometric predictors of child mortality. We explored whether the decline in child mortality over recent decades could be explained by changes in children's MUAC.

Methods: This prospective study analysed individual-level data from 47 731 children from the capital of Guinea-Bissau followed from 3 months until 36 months of age over 2003 to 2016.

The Effect of a Second Dose of Measles Vaccine at 18 Months of Age on Nonaccidental Deaths and Hospital Admissions in Guinea-Bissau: Interim Analysis of a Randomized Controlled Trial.

Background: The world is set on the eradication of measles. Continuation of the measles vaccine (MV) after eradication could still reduce morbidity because the MV has so-called beneficial nonspecific effects. We evaluated the effect of a "booster" dose of the MV on overall severe morbidity.

Measles Vaccination in Presence of Measles Antibody May Enhance Child Survival.

In trials of early two-dose measles vaccination (MV), with the first dose being given before 9 months of age, vaccination in the presence of maternal antibody reduced mortality 2- to 3-fold compared with MV in the presence of no measles antibody. We tested this finding in two historical studies in which the children had received one dose of MV. We used data from a surveillance study of seroconversion after standard-titer MV (Schwarz strain) (Study 1) and a trial of early medium-titer MV (Edmonston-Zagreb strain) in which a pre-vaccination blood sample had been collected (Study 2).

Determinants of BCG scarification among children in rural Guinea-Bissau: A prospective cohort study.

Background: Bacillus Calmette-Guérin (BCG) vaccination may have beneficial non-specific effects on child survival, the effects being stronger for children developing a scar. In a prospective cohort study, we examined determinants for not developing a BCG scar within 6 months of vaccination.

Methods: Bandim Health Project (BHP) runs a Health and Demographic Surveillance System site in rural Guinea-Bissau.

Randomized Trial of 2 Versus 1 Dose of Measles Vaccine: Effect on Hospital Admission of Children After 9 Months of Age.

Background: Two doses of measles vaccine (MV) might reduce the nonmeasles mortality rate more than 1 dose of MV does. The effect of 2 versus 1 dose on morbidity has not been examined. Within a randomized trial of the effect of 2 doses versus 1 dose of MV on mortality in Guinea-Bissau, we investigated the effect on hospital admissions.

Does oral polio vaccine have non-specific effects on all-cause mortality? Natural experiments within a randomised controlled trial of early measles vaccine.

Background: BCG and measles vaccine (MV) may have beneficial non-specific effects (NSEs). If an unplanned intervention with a vaccine (a natural experiment) modifies the estimated effect in a randomised controlled trial (RCT), this suggests NSEs. We used this approach to test NSEs of triple oral polio vaccine (OPV).

Introduction of standard measles vaccination in an urban African community in 1979 and overall child survival: a reanalysis of data from a cohort study.

Objective: To examine the effect of the first introduction of measles vaccine (MV) in Guinea-Bissau in 1979.

Setting: Urban community study of the anthropometric status of all children under 6 years of age.

Participants: The study cohort included 1451 children in December 1978; 82% took part in the anthropometric survey.

Contrasting female-male mortality ratios after routine vaccinations with pentavalent vaccine versus measles and yellow fever vaccine. A cohort study from urban Guinea-Bissau.

Background: In addition to protection against the target diseases, vaccines may have non-specific effects (NSEs). Measles vaccine (MV) has beneficial NSEs, providing protection against non-measles deaths, most so for girls. By contrast, though protecting against diphtheria, tetanus and pertussis, DTP vaccine is associated with increased female mortality relative to male mortality.

Is early measles vaccination better than later measles vaccination?

WHO recommends delaying measles vaccination (MV) until maternal antibody has waned. However, early MV may improve child survival by reducing mortality from conditions other than measles infection. We tested whether early MV improves child survival compared with later MV.

Interaction between neonatal vitamin A supplementation and timing of measles vaccination: a retrospective analysis of three randomized trials from Guinea-Bissau.

Background: In Guinea-Bissau we conducted three trials of neonatal vitamin A supplementation (NVAS) from 2002 to 2008. None of the trials found a beneficial effect on mortality. From 2003 to 2007, an early measles vaccine (MV) trial was ongoing, randomizing children 1:2 to early MV at 4.

Two different doses of supplemental vitamin A did not affect mortality of normal-birth-weight neonates in Guinea-Bissau in a randomized controlled trial.

Whether neonatal vitamin A supplementation (NVAS) should be policy in areas with vitamin A deficiency is debated. We observed that a smaller dose of vitamin A may decrease mortality more than a larger dose and conducted a randomized, double-blind, placebo-controlled trial in Guinea-Bissau with the primary aim of comparing the effect of 50,000 with 25,000 IU neonatal vitamin A on infant mortality. The secondary aim was to study the effect of NVAS vs.

Measles vaccination in the presence or absence of maternal measles antibody: impact on child survival.

Background: Measles vaccine (MV) has a greater effect on child survival when administered in early infancy, when maternal antibody may still be present.

Methods: To test whether MV has a greater effect on overall survival if given in the presence of maternal measles antibody, we reanalyzed data from 2 previously published randomized trials of a 2-dose schedule with MV given at 4-6 months and at 9 months of age. In both trials antibody levels had been measured before early measles vaccination.

The effect of early measles vaccination on thymic size. A randomized study from Guinea-Bissau.

Unlabelled: In low-income countries early measles vaccine (MV) is associated with reduced child mortality which cannot be explained by prevention of measles. A large thymus gland in infancy is also associated with reduced mortality. We hypothesized that early MV is associated with increased thymic size.

A randomized trial of a standard dose of Edmonston-Zagreb measles vaccine given at 4.5 months of age: effect on total hospital admissions.

Observational studies and trials from low-income countries indicate that measles vaccine has beneficial nonspecific effects, protecting against non-measles-related mortality. It is not known whether measles vaccine protects against hospital admissions. Between 2003 and 2007, 6417 children who had received the third dose of diphtheria, tetanus, and pertussis vaccine were randomly assigned to receive measles vaccine at 4.

The optimal age of measles immunisation in low-income countries: a secondary analysis of the assumptions underlying the current policy.

Objective: The current policy of measles vaccination at 9 months of age was decided in the mid-1970s. The policy was not tested for impact on child survival but was based on studies of seroconversion after measles vaccination at different ages. The authors examined the empirical evidence for the six underlying assumptions.

The effect of high-dose vitamin A supplementation at birth on measles incidence during the first 12 months of life in boys and girls: an unplanned study within a randomised trial.

Vitamin A treatment reduces mortality during acute measles infection, and vitamin A supplementation (VAS) to children above 6 months of age may reduce the incidence of measles infection. The effect of VAS at birth on measles incidence is unknown. In a randomised placebo-controlled trial in Guinea-Bissau, normal-birth-weight newborns were randomised to 50 000 IU (15 mg) VAS or placebo.

Non-specific effects of standard measles vaccine at 4.5 and 9 months of age on childhood mortality: randomised controlled trial.

Objective: To examine in a randomised trial whether a 25% difference in mortality exists between 4.5 months and 3 years of age for children given two standard doses of Edmonston-Zagreb measles vaccines at 4.5 and 9 months of age compared with those given one dose of measles vaccine at 9 months of age (current policy).

Protective efficacy of standard Edmonston-Zagreb measles vaccination in infants aged 4.5 months: interim analysis of a randomised clinical trial.

Objective: To examine the protective efficacy of measles vaccination in infants in a low income country before 9 months of age.

Design: Randomised clinical trial.

Participants: 1333 infants aged 4.

Thymus size at 6 months of age and subsequent child mortality.

Objective: To examine determinants of thymus size at age 6 months and investigate whether thymus size at this age is a determinant of subsequent mortality.

Study Design: Thymus size was measured by transsternal sonography in 923 6-month-old children participating in a measles vaccination trial in Guinea-Bissau.

Results: Thymus size was strongly associated with anthropometric measurements.

Prophylactic antibiotics to prevent pneumonia and other complications after measles: community based randomised double blind placebo controlled trial in Guinea-Bissau.

Objective: To investigate whether prophylactic antibiotics can prevent complications of measles.

Design: Community based, randomised, double blind, placebo controlled trial.

Setting: Bandim Health Project study area in Bissau, Guinea-Bissau, west Africa.

Hepatitis B vaccination associated with higher female than male mortality in Guinea-bissau: an observational study.

Objective: Studies from high mortality areas have suggested that diphtheria-tetanus-pertussis may be associated with an increase in the mortality of girls relative to boys. We therefore examined whether hepatitis B vaccine (HBV) was associated with sex-specific differences in mortality.

Design: As part of a randomized trial of measles vaccine, a subcohort of 876 children was offered HBV at 7(1/2), 9 and 10(1/2) months of age.

Low birth weight infants and Calmette-Guérin bacillus vaccination at birth: community study from Guinea-Bissau.

Background: In developing countries, low birth weight (LBW) children are often not vaccinated with Calmette-Guérin bacillus (BCG) at birth. Recent studies have suggested that BCG may have a nonspecific beneficial effect on infant mortality. We evaluated the consequences of not vaccinating LBW children at birth in Guinea-Bissau.