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Concept: Bill & Melinda Gates Foundation


Background Although the rising pandemic of obesity has received major attention in many countries, the effects of this attention on trends and the disease burden of obesity remain uncertain. Methods We analyzed data from 68.5 million persons to assess the trends in the prevalence of overweight and obesity among children and adults between 1980 and 2015. Using the Global Burden of Disease study data and methods, we also quantified the burden of disease related to high body-mass index (BMI), according to age, sex, cause, and BMI in 195 countries between 1990 and 2015. Results In 2015, a total of 107.7 million children and 603.7 million adults were obese. Since 1980, the prevalence of obesity has doubled in more than 70 countries and has continuously increased in most other countries. Although the prevalence of obesity among children has been lower than that among adults, the rate of increase in childhood obesity in many countries has been greater than the rate of increase in adult obesity. High BMI accounted for 4.0 million deaths globally, nearly 40% of which occurred in persons who were not obese. More than two thirds of deaths related to high BMI were due to cardiovascular disease. The disease burden related to high BMI has increased since 1990; however, the rate of this increase has been attenuated owing to decreases in underlying rates of death from cardiovascular disease. Conclusions The rapid increase in the prevalence and disease burden of elevated BMI highlights the need for continued focus on surveillance of BMI and identification, implementation, and evaluation of evidence-based interventions to address this problem. (Funded by the Bill and Melinda Gates Foundation.).

Concepts: Cancer, Nutrition, Obesity, Overweight, Body mass index, Body shape, Bariatrics, Bill & Melinda Gates Foundation


Background We hypothesized that mass distribution of a broad-spectrum antibiotic agent to preschool children would reduce mortality in areas of sub-Saharan Africa that are currently far from meeting the Sustainable Development Goals of the United Nations. Methods In this cluster-randomized trial, we assigned communities in Malawi, Niger, and Tanzania to four twice-yearly mass distributions of either oral azithromycin (approximately 20 mg per kilogram of body weight) or placebo. Children 1 to 59 months of age were identified in twice-yearly censuses and were offered participation in the trial. Vital status was determined at subsequent censuses. The primary outcome was aggregate all-cause mortality; country-specific rates were assessed in prespecified subgroup analyses. Results A total of 1533 communities underwent randomization, 190,238 children were identified in the census at baseline, and 323,302 person-years were monitored. The mean (±SD) azithromycin and placebo coverage over the four twice-yearly distributions was 90.4±10.4%. The overall annual mortality rate was 14.6 deaths per 1000 person-years in communities that received azithromycin (9.1 in Malawi, 22.5 in Niger, and 5.4 in Tanzania) and 16.5 deaths per 1000 person-years in communities that received placebo (9.6 in Malawi, 27.5 in Niger, and 5.5 in Tanzania). Mortality was 13.5% lower overall (95% confidence interval [CI], 6.7 to 19.8) in communities that received azithromycin than in communities that received placebo (P<0.001); the rate was 5.7% lower in Malawi (95% CI, -9.7 to 18.9), 18.1% lower in Niger (95% CI, 10.0 to 25.5), and 3.4% lower in Tanzania (95% CI, -21.2 to 23.0). Children in the age group of 1 to 5 months had the greatest effect from azithromycin (24.9% lower mortality than that with placebo; 95% CI, 10.6 to 37.0). Serious adverse events occurring within a week after administration of the trial drug or placebo were uncommon, and the rate did not differ significantly between the groups. Evaluation of selection for antibiotic resistance is ongoing. Conclusions Among postneonatal, preschool children in sub-Saharan Africa, childhood mortality was lower in communities randomly assigned to mass distribution of azithromycin than in those assigned to placebo, with the largest effect seen in Niger. Any implementation of a policy of mass distribution would need to strongly consider the potential effect of such a strategy on antibiotic resistance. (Funded by the Bill and Melinda Gates Foundation; MORDOR number, NCT02047981 .).

Concepts: Africa, Sub-Saharan Africa, Sahara, Malawi, United Nations, Bill & Melinda Gates Foundation, Bill Gates, Melinda Gates


Synthetic biology has the potential to contribute breakthrough innovations to the pursuit of new global health solutions. Wishing to harness the emerging tools of synthetic biology for the goals of global health, in 2011 the Bill & Melinda Gates Foundation put out a call for grant applications to “Apply Synthetic Biology to Global Health Challenges” under its “Grand Challenges Explorations” program. A highly diverse pool of over 700 applications was received. Proposed applications of synthetic biology to global health needs included interventions such as therapeutics, vaccines, and diagnostics, as well as strategies for biomanufacturing, and the design of tools and platforms that could further global health research.

Concepts: Medicine, Research, Computer program, Innovation, Bill & Melinda Gates Foundation, The Bill, Bill Gates, Melinda Gates


The pneumonia team at the Bill & Melinda Gates Foundation congratulates the Pneumonia Etiology Research for Child Health (PERCH) study on delivering on their grant to collect high-quality data from thousands of children with World Health Organization-defined severe and very severe pneumonia and from controls in 9 diverse sites in 7 low- and middle-income countries. This supplement sets the foundation to understanding this complex study by providing an in-depth description of the study methodology, including discussion of key aspects such as antibiotic pretreatment, chest radiograph interpretation, utility of induced sputum in children, measurement of pathogen density, and use of C-reactive protein, and how these affect pneumonia etiology.

Concepts: Medicine, Bacteria, Pneumonia, Child, Bill & Melinda Gates Foundation, The Bill, Bill Gates, Melinda Gates


BACKGROUND: Fast weight gain and linear growth in children in low-income and middle-income countries are associated with enhanced survival and improved cognitive development, but might increase risk of obesity and related adult cardiometabolic diseases. We investigated how linear growth and relative weight gain during infancy and childhood are related to health and human capital outcomes in young adults. METHODS: We used data from five prospective birth cohort studies from Brazil, Guatemala, India, the Philippines, and South Africa. We investigated body-mass index, systolic and diastolic blood pressure, plasma glucose concentration, height, years of attained schooling, and related categorical indicators of adverse outcomes in young adults. With linear and logistic regression models, we assessed how these outcomes relate to birthweight and to statistically independent measures representing linear growth and weight gain independent of linear growth (relative weight gain) in three age periods: 0-2 years, 2 years to mid-childhood, and mid-childhood to adulthood. FINDINGS: We obtained data for 8362 participants who had at least one adult outcome of interest. A higher birthweight was consistently associated with an adult body-mass index of greater than 25 kg/m(2) (odds ratio 1·28, 95% CI 1·21-1·35) and a reduced likelihood of short adult stature (0·49, 0·44-0·54) and of not completing secondary school (0·82, 0·78-0·87). Faster linear growth was strongly associated with a reduced risk of short adult stature (age 2 years: 0·23, 0·20-0·52; mid-childhood: 0·39, 0·36-0·43) and of not completing secondary school (age 2 years: 0·74, 0·67-0·78; mid-childhood: 0·87, 0·83-0·92), but did raise the likelihood of overweight (age 2 years: 1·24, 1·17-1·31; mid-childhood: 1·12, 1·06-1·18) and elevated blood pressure (age 2 years: 1·12, 1·06-1·19; mid-childhood: 1·07, 1·01-1·13). Faster relative weight gain was associated with an increased risk of adult overweight (age 2 years: 1·51, 1·43-1·60; mid-childhood: 1·76, 1·69-1·91) and elevated blood pressure (age 2 years: 1·07, 1·01-1·13; mid-childhood: 1·22, 1·15-1·30). Linear growth and relative weight gain were not associated with dysglycaemia, but a higher birthweight was associated with decreased risk of the disorder (0·89, 0·81-0·98). INTERPRETATION: Interventions in countries of low and middle income to increase birthweight and linear growth during the first 2 years of life are likely to result in substantial gains in height and schooling and give some protection from adult chronic disease risk factors, with few adverse trade-offs. FUNDING: Wellcome Trust and Bill & Melinda Gates Foundation.

Concepts: Cohort study, Epidemiology, Hypertension, Obesity, Blood pressure, Relative risk, High school, Bill & Melinda Gates Foundation


Background The prevalence of facility-based childbirth in low-resource settings has increased dramatically during the past two decades, yet gaps in the quality of care persist and mortality remains high. The World Health Organization (WHO) Safe Childbirth Checklist, a quality-improvement tool, promotes systematic adherence to practices that have been associated with improved childbirth outcomes. Methods We conducted a matched-pair, cluster-randomized, controlled trial in 60 pairs of facilities across 24 districts of Uttar Pradesh, India, testing the effect of the BetterBirth program, an 8-month coaching-based implementation of the Safe Childbirth Checklist, on a composite outcome of perinatal death, maternal death, or maternal severe complications within 7 days after delivery. Outcomes - assessed 8 to 42 days after delivery - were compared between the intervention group and the control group with adjustment for clustering and matching. We also compared birth attendants' adherence to 18 essential birth practices in 15 matched pairs of facilities at 2 and 12 months after the initiation of the intervention. Results Of 161,107 eligible women, we enrolled 157,689 (97.9%) and determined 7-day outcomes for 157,145 (99.7%) mother-newborn dyads. Among 4888 observed births, birth attendants' mean practice adherence was significantly higher in the intervention group than in the control group (72.8% vs. 41.7% at 2 months; 61.7% vs. 43.9% at 12 months; P<0.001 for both comparisons). However, there was no significant difference between the trial groups either in the composite primary outcome (15.1% in the intervention group and 15.3% in the control group; relative risk, 0.99; 95% confidence interval, 0.83 to 1.18; P=0.90) or in secondary maternal or perinatal adverse outcomes. Conclusions Birth attendants' adherence to essential birth practices was higher in facilities that used the coaching-based WHO Safe Childbirth Checklist program than in those that did not, but maternal and perinatal mortality and maternal morbidity did not differ significantly between the two groups. (Funded by the Bill and Melinda Gates Foundation; Clinical Trials number, NCT02148952 .).

Concepts: Childbirth, Death, Medical statistics, Obstetrics, Maternal death, Perinatal mortality, Bill & Melinda Gates Foundation, Bill Gates


Background Implementation of an ivermectin-based community treatment strategy for the elimination of onchocerciasis or lymphatic filariasis has been delayed in Central Africa because of the occurrence of serious adverse events, including death, in persons with high levels of circulating Loa loa microfilariae. The LoaScope, a field-friendly diagnostic tool to quantify L. loa microfilariae in peripheral blood, enables rapid, point-of-care identification of persons at risk for serious adverse events. Methods A test-and-not-treat strategy was used in the approach to ivermectin treatment in the Okola health district in Cameroon, where the distribution of ivermectin was halted in 1999 after the occurrence of fatal events related to L. loa infection. The LoaScope was used to identify persons with an L. loa microfilarial density greater than 20,000 microfilariae per milliliter of blood, who were considered to be at risk for serious adverse events, and exclude them from ivermectin distribution. Active surveillance for posttreatment adverse events was performed daily for 6 days. Results From August through October 2015, a total of 16,259 of 22,842 persons 5 years of age or older (71.2% of the target population) were tested for L. loa microfilaremia. Among the participants who underwent testing, a total of 15,522 (95.5%) received ivermectin, 340 (2.1%) were excluded from ivermectin distribution because of an L. loa microfilarial density above the risk threshold, and 397 (2.4%) were excluded because of pregnancy or illness. No serious adverse events were observed. Nonserious adverse events were recorded in 934 participants, most of whom (67.5%) had no detectable L. loa microfilariae. Conclusions The LoaScope-based test-and-not-treat strategy enabled the reimplementation of community-wide ivermectin distribution in a heretofore “off limits” health district in Cameroon and is a potentially practical approach to larger-scale ivermectin treatment for lymphatic filariasis and onchocerciasis in areas where L. loa infection is endemic. (Funded by the Bill and Melinda Gates Foundation and others.).

Concepts: Parasitic diseases, Filariasis, Neglected diseases, Ivermectin, Loa loa filariasis, Bill & Melinda Gates Foundation, Bill Gates, Melinda Gates


BACKGROUND: As Chagas disease continues to expand beyond tropical and subtropical zones, a growing need exists to better understand its resulting economic burden to help guide stakeholders such as policy makers, funders, and product developers. We developed a Markov simulation model to estimate the global and regional health and economic burden of Chagas disease from the societal perspective. METHODS: Our Markov model structure had a 1 year cycle length and consisted of five states: acute disease, indeterminate disease, cardiomyopathy with or without congestive heart failure, megaviscera, and death. Major model parameter inputs, including the annual probabilities of transitioning from one state to another, and present case estimates for Chagas disease came from various sources, including WHO and other epidemiological and disease-surveillance-based reports. We calculated annual and lifetime health-care costs and disability-adjusted life-years (DALYs) for individuals, countries, and regions. We used a discount rate of 3% to adjust all costs and DALYs to present-day values. FINDINGS: On average, an infected individual incurs US$474 in health-care costs and 0·51 DALYs annually. Over his or her lifetime, an infected individual accrues an average net present value of $3456 and 3·57 DALYs. Globally, the annual burden is $627·46 million in health-care costs and 806 170 DALYs. The global net present value of currently infected individuals is $24·73 billion in health-care costs and 29 385 250 DALYs. Conversion of this burden into costs results in annual per-person costs of $4660 and lifetime per-person costs of $27 684. Global costs are $7·19 billion per year and $188·80 billion per lifetime. More than 10% of these costs emanate from the USA and Canada, where Chagas disease has not been traditionally endemic. A substantial proportion of the burden emerges from lost productivity from cardiovascular disease-induced early mortality. INTERPRETATION: The economic burden of Chagas disease is similar to or exceeds those of other prominent diseases globally (eg, rotavirus $2·0 billion, cervical cancer $4·7 billion) even in the USA (Lyme disease $2·5 billion), where Chagas disease has not been traditionally endemic, suggesting an economic argument for more attention and efforts towards control of Chagas disease. FUNDING: Bill & Melinda Gates Foundation, the National Institute of General Medical Sciences Models of Infectious Disease Agent Study.

Concepts: Medicine, Epidemiology, Infectious disease, Cardiomyopathy, Heart failure, Infection, Chagas disease, Bill & Melinda Gates Foundation


Background Aerosolized vaccine can be used as a needle-free method of immunization against measles, a disease that remains a major cause of illness and death. Data on the immunogenicity of aerosolized vaccine against measles in children are inconsistent. Methods We conducted an open-label noninferiority trial involving children 9.0 to 11.9 months of age in India who were eligible to receive a first dose of measles vaccine. Children were randomly assigned to receive a single dose of vaccine by means of either aerosol inhalation or a subcutaneous injection. The primary end points were seropositivity for antibodies against measles and adverse events 91 days after vaccination. The noninferiority margin was 5 percentage points. Results A total of 1001 children were assigned to receive aerosolized vaccine, and 1003 children were assigned to receive subcutaneous vaccine; 1956 of all the children (97.6%) were followed to day 91, but outcome data were missing for 331 children because of thawed specimens. In the per-protocol population, data on 1560 of 2004 children (77.8%) could be evaluated. At day 91, a total of 662 of 775 children (85.4%; 95% confidence interval [CI], 82.5 to 88.0) in the aerosol group, as compared with 743 of 785 children (94.6%; 95% CI, 92.7 to 96.1) in the subcutaneous group, were seropositive, a difference of -9.2 percentage points (95% CI, -12.2 to -6.3). Findings were similar in the full-analysis set (673 of 788 children in the aerosol group [85.4%] and 754 of 796 children in the subcutaneous group [94.7%] were seropositive at day 91, a difference of -9.3 percentage points [95% CI, -12.3 to -6.4]) and after multiple imputation of missing results. No serious adverse events were attributable to measles vaccination. Adverse-event profiles were similar in the two groups. Conclusions Aerosolized vaccine against measles was immunogenic, but, at the prespecified margin, the aerosolized vaccine was inferior to the subcutaneous vaccine with respect to the rate of seropositivity. (Funded by the Bill and Melinda Gates Foundation; Measles Aerosol Vaccine Project Clinical Trials Registry-India number, CTRI/2009/091/000673 .).

Concepts: Clinical trial, Vaccine, Vaccination, Immunology, MMR vaccine, Bill & Melinda Gates Foundation, Bill Gates, Melinda Gates


BACKGROUND: Data for trends in contraceptive use and need are necessary to guide programme and policy decisions and to monitor progress towards Millennium Development Goal 5, which calls for universal access to contraceptive services. We therefore aimed to estimate trends in contraceptive use and unmet need in developing countries in 2003, 2008, and 2012 . METHODS: We obtained data from national surveys for married and unmarried women aged 15-49 years in regions and subregions of developing countries. We estimated trends in the numbers and proportions of women wanting to avoid pregnancy, according to whether they were using modern contraceptives, or had unmet need for modern methods (ie, using no methods or a traditional method). We used comparable data sources and methods for three reference years (2003, 2008, and 2012). National survey data were available for 81-98% of married women using and with unmet need for modern methods. FINDINGS: The number of women wanting to avoid pregnancy and therefore needing effective contraception increased substantially, from 716 million (54%) of 1321 million in 2003, to 827 million (57%) of 1448 million in 2008, to 867 million (57%) of 1520 million in 2012. Most of this increase (108 million) was attributable to population growth. Use of modern contraceptive methods also increased, and the overall proportion of women with unmet need for modern methods among those wanting to avoid pregnancy decreased from 29% (210 million) in 2003, to 26% (222 million) in 2012. However, unmet need for modern contraceptives was still very high in 2012, especially in sub-Saharan Africa (53 million [60%] of 89 million), south Asia (83 million [34%] of 246 million), and western Asia (14 million [50%] of 27 million). Moreover, a shift in the past decade away from sterilisation, the most effective method, towards injectable drugs and barrier methods, might have led to increases in unintended pregnancies in women using modern methods. INTERPRETATION: Achievement of the desired number and healthy timing of births has important benefits for women, families, and societies. To meet the unmet need for modern contraception, countries need to increase resources, improve access to contraceptive services and supplies, and provide high-quality services and large-scale public education interventions to reduce social barriers. Our findings confirm a substantial and unfinished agenda towards meeting of couples' reproductive needs. FUNDING: UK Department for International Development, the Bill & Melinda Gates Foundation, and the UN Population Fund (UNFPA).

Concepts: Pregnancy, Birth control, Emergency contraception, Marriage, Abortion, Condom, Need, Bill & Melinda Gates Foundation