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Yayehyirad Tassachew,1– 3 Tamrat Abebe,1 Yeshambel Belyhun,4 Tezazu Teffera,5 Abate Bane Shewaye,6,7 Hailemichael Desalegn,8 Henok Andualem,9 Abiy Kinfu,10 Andargachew Mulu,2 Adane Mihret,1,2 Rawleigh Howe,2 Abraham Aseffa2 1Department of Microbiology, Immunology, and Parasitology, School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia; 2Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia; 3School of Medical Laboratory Sciences, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia; 4School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia; 5Department of Surgery, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia; 6Department of Internal Medicine, School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia; 7Adera Medical Center PLC, Addis Ababa, Ethiopia; 8Department of Internal Medicine, St. Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia; 9Department of Medical Laboratory Science, College of Medicine and Health Sciences, Debre Tabor University, Debre Tabor, Ethiopia; 10Ethiopian National Blood Bank Service, Addis Ababa, EthiopiaCorrespondence: Yayehyirad Tassachew, Department of Microbiology, Immunology & Parasitology, School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia, Tel +251-916829464, Email seamyah@gmail.com; tassachewy@gmail.comBackground: The efficient use of antiretroviral drugs has significantly reduced AIDS-related morbidities and mortalities; however, mortality due to non-AIDS-related end-stage liver diseases is escalating in those living with HIV.Objective: The study was designed to determine the prevalence of HIV and its co-infection with HBV and HCV among chronic liver disease (CLD) patients in Ethiopia.Methods: Three hundred and forty-five CLD patients were included in this study in two groups: Hepatocellular carcinoma (HCC) (n=128) and non-HCC (n=217) patients. The non-HCC group comprised patients with advanced liver disease (n=98) and chronic hepatitis (n=119). Enzyme immunoassays were used to determine HBV and HCV infection markers. In addition, a serial rapid HIV testing algorithm was employed to screen HIV infection.Results: Regardless of the stage of liver disease, the overall frequency of HIV was 4.3% (15/345), with a 2% (7/345) and 0.3% (1/345) of HIV/HBV and HIV/HCV co-infection rate. Of all HIV-infected patients (n=15), 46.7% (7/15) and 6.7% (1/15) were co-infected with HBV (HBsAg+HBcAb+) and HCV (anti-HCV+ HCV-RNA+), respectively, and 86.7% (13/15) exhibited a marker of HBV exposure (total HBcAb+). Overall, the frequency of HIV and its co-infection with HBV was more noticeable among HCC than non-HCC patients [8.6% (11/128) vs 1.8 (4/217), p=0.005 and 3.9% (5/128) vs 0.9% (2/217), p=0.1]. The rate of HIV mono-infection was 3.9% (5/128) vs 0.9% (2/217) among HCC and non-HCC patients.Conclusion: The frequency of HIV and its co-infections with HBV/HCV exhibited an increasing pattern with the severity of the liver disease. Thus, screening all HIV-positive patients for HBV and HCV infection and all CLD patients for HIV infection and taking necessary preventive measures would be an essential strategy to prevent the progression of CLD and death related to liver disease in people living with HIV.Keywords: HIV, HBV, HCV, HCC, non-AIDS liver diseases

Abstract Background In Ethiopia, 79 million people live in soil transmitted helminths endemic areas. The Ethiopia established a National goal to eradicate STH transmission by 2025. To meet that goal, it is imperative that data is acquired on community helminth infection risk. This study examined the prevalence of STH and risk factors for infection in vegetable farmers working on Akaki River Bank, Addis Ababa, Ethiopia. Methods A cross-sectional study was conducted between November 7, 2022, and June 2023. A stratified random sampling was used to select farming households. Two hundred and sixteen farmers were enrolled in the study. Data on socio-demographic, WASH, wastewater irrigation related factors were collected by trained data collectors using a structured questionnaire. Kato-Katz concentration was utilized to detect STH. The data were entered using EpiData 3.1 and analyzed with Stata 14.0, using p-values less than 0.05 to identify significant factors. Logistic regression was used to identify independent risk factors for infection. Results The prevalence of STH was 22.2% (95% CI = 13.6-27.9%), with Ascaris lumbricoides being the most common (11.1%), followed by hookworm (7.4%), and Trichuris trichiura (3.7%). Low income levels (AOR = 1.85, 95% CI = 1.25–5.99), lack of handwashing before eating (AOR = 2.25, 95% CI = 1.58 − 11.3), absence of fingernails cleanliness (AOR = 1.97, 95% CI = 1.74–39.5), not wearing shoes at work (AOR = 3.4, 95% CI = 2.98–82.2), touching the face with dirty hands (AOR = 2.9, 95% CI = 0.68–28.2), washing vegetables with irrigation wastewater (AOR = 2.1, 95% CI = 1.95–45.2), and not wearing protective clothing during farming activities (AOR = 2.99, 95% CI = 1.58 − 22.4) were the significant risk factors for infection with STH. Conclusion Of the farming communities examined in this study, one of the five was found to be infected with soil transmitted helminth. This research has shown clear risk factors for STH infection including: lack of personal hygiene practices, insufficient sanitation access, and limited use of protective equipment. To achieve the national goal, there is a need for farming communities to understand preventative risks of infection, improve WASH (Water access, sanitation and hygine) practices, WASH access, protective equipment, and health education.

Abstract Background Untreated or inadequately treated wastewater carrying human feces can host helminth eggs and larvae, contaminating the soil and plants that are irrigated with it. In Addis Ababa, farmers use untreated wastewater to grow vegetables; however, there are little data currently available published on vegetables' contribution to the prevalence of helminth among female farmers along the Akaki River, in Addis Ababa, Ethiopia. Methods A cross-sectional study was conducted in Addis Ababa City in February 2022. A stratified random sampling method was used to sample farming households. The sample size for each district was determined by a proportional allocation to the total number of households in the area. Two hundred and fifty-two composite vegetable samples and 101 farmers’ stool samples were collected and analyzed for helminth prevalence. Data on socio-demographics were collected by trained data collators using a structured questionnaire. Kato-Katz concentration was used to detect STH from a stool sample. Stata version 14.0 was used to process the data. Poisson regression was used to identify the association between STH prevalence in the vegetable and the farm's stool. Results Helminths were found in 67.5% of vegetables sampled and 20.8% of female farmers' stools. Ascaris lumbricoides eggs (vegetable 48.4% and stool 9.9%) were identified in all analyzed samples. Hookworm eggs (vegetable 13.1% and stool 8.9%) and Trichuris trichiura eggs (vegetable 5.9% and stool 2%) were also isolated. The total number of helminth eggs present in wastewater-irrigated vegetables and female farmers’ stool had a positive association (p

Abstract Background Malaria is a major public health concern in Ethiopia, where more than half of the population lives in malaria risk areas. While several studies have been conducted in different eco-epidemiological settings in Ethiopia, there is a notable scarcity of data on the prevalence of malaria in the Gindabarat district. Therefore, this study aimed to analyse 10-year trend of malaria prevalence in Gindabarat district, West Shawa Zone of Oromia, Western Ethiopia. Methods A retrospective laboratory record review was conducted at Gindabarat General Hospital and Gindabarat District Health Office from September 2011 to August 2020. The retrieved data included the date of examination, age, sex and laboratory results of the blood smears, including the Plasmodium species identified. Data were summarized and presented in the form of tables, figures, and frequencies to present the results. The data were analysed using SPSS (version 25.0) and Microsoft Excel. Results Over the course of 10 years, a total of 11,478 blood smears were examined in the public health facilities in the district. Of the total blood smears examined, 1372 (11.95%) were microscopically confirmed malaria. Plasmodium falciparum, Plasmodium vivax and mixed infections (P. falciparum and P. vivax) accounted for 70.77%, 20.55% and 8.67% of the cases, respectively. Malaria prevalence was significantly higher among individuals aged ≥ 15 years (12.60%, x2 = 13.6, df = 2, p = 0.001) and males (14.21%, x2 = 59.7, df = 1, p = 0.001). The highest number of malaria cases was recorded from September to November. Conclusion Malaria remains a public health problem in the district. P. falciparum was the most predominant parasite species in the area. Malaria prevalence was significantly higher among individuals aged ≥ 15 years and males. There was a remarkable fluctuation in the number of malaria cases in different months and years. In the study area malaria cases peaked in 2015 and 2017 then decreasing from 2017 to 2019, with sharp increase in 2020. Moreover, this study showed malaria cases were reported in all seasons and months, but the highest was observed from September to November. Strengthening malaria control activities is essential to further reduce the burden of malaria and pave the way for the anticipated elimination.

Abstract Background Helminth infections are a public health issue in countries with poor sanitation facilities. However, there little information on the epidemiological association between helminths in wastewater and soil samples and rates of helminth infection among farming households along the Akaki River in Addis Ababa, Ethiopia. Methods A cross-sectional study was conducted between November 2021 and February 2022. A stratified random sampling technique was used to select farming households. The sample size for each district was determined by a proportionate allocation to the number of households. From wastewater-irrigated farms, 70 wastewater samples, 28 soil samples, and 86 farmers' stool samples were collected and analyzed for helminths. A questionnaire was used to gather ethnographic data, about farming households, whereas wastewater and soil sample analysis was used to generate quantitative data on helminth loads. The data were systematically analysed by developing themes, and bias evaluated using triangulation validation methodologies. Potential pathways to helminth infection were evaluated by measuring. Total number of helminth eggs in wastewater, soil samples and farmer's stools was investigated using Poisson regression. Results In this study, 82.9% of wastewater samples, 57.1% of soil samples, and 18.6% of farmers' stool samples contained helminth eggs. The most prevalent helminth was Ascaris lumbricoides in all samples (wastewater 67%, soil 25%, and stool 10.5%), followed by hookworm (wastewater 10%, soil 21.4%, and stool 6.9%) and Trichuris trichiura eggs (wastewater 5.7%, soil 10.7%, and stool 1.2%). There was a positive association between the total number of helminth eggs in wastewater and soil samples with counts in farmers’ stool. The Poisson regression coefficients for wastewater and soil were, 1.63 (95% CI = 1.34–1.92) and 1.70 (95% CI = 1.39–2.01), (p

Abstract Background Unhealthy alcohol use is a leading contributor to premature death and disability worldwide. The World Health Organization’s Global Status Report on Alcohol and Health ranked South Africa as having one of the riskiest patterns of alcohol consumption, which calls for intervention. Recognising the need for effective primary care interventions, particularly in the absence of appropriate alcohol-related harm reduction policies at national and local levels, this paper highlights the opportunities and challenges associated with a two-pronged, community-centred approach to the identification of unhealthy alcohol use and interventions. Methods This approach included the use of the Alcohol Use Disorders Identification Test–Consumption (AUDIT-C) as a means of screening to identify individuals at moderate (score of 5–7) to high risk (score of 8 +) alcohol use, raising awareness, and investigating the potential utility of brief advice and referrals as a means of reducing risk. Results Of the 54,187 participants, 43.0% reported engaging in moderate-risk alcohol consumption, with 22.1% reporting high-risk alcohol consumption. Resistance to brief advice was observed to increase with higher AUDIT-C scores. Similarly, participants engaging in high-risk alcohol consumption were resistant to accepting treatment referrals, with fewer than 10% open to receiving a referral. Conclusions While men were most likely to report patterns of high-risk alcohol consumption, they were more resistant to accepting referrals. Additionally, participants who were willing to receive brief advice were often resistant to taking active steps to alter their alcohol use. This study highlights the need to consider how to prevent harmful patterns of alcohol use effectively and holistically, especially in low socioeconomic settings through primary health care and community services.

Thin-film composite (TFC) membranes containing a metal–polyphenol network (MPN)-based selective layer were fabricated on a porous polyacrylonitrile support. The MPN layer was formed through coordination-based self-assembly between plant-based tannic acid (TA) and an Fe3+ ion. For the first time, we demonstrate that TFC membranes containing TA-Fe3+ selective layers can separate small organic solutes in aqueous media from equimolar mixtures of solutes. The effect of the assembly time on the characteristics and performance of the fabricated selective layer was investigated. An increase in the assembly time led to the formation of selective layers with smaller effective pore sizes. The tannic acid–Fe3+ selective layer exhibited a low rejection towards neutral solutes riboflavin and poly(ethylene glycol) while high rejections were observed for anionic dyes of orange II and naphthol green B. Permeation selectivities in the range of 2–27 were achieved between neutral and charged dyes in both single- and mixed-solute experiments, indicating the significant role of Donnan exclusion and the charge-selective nature of the membranes. The rejection efficiency improved with an increasing assembly time. Overall, this study demonstrates that the assembly time is a vital casting parameter for controlling the permeance, rejection and selectivity of thin-film composite membranes with a tannic acid–Fe3+ selective layer.

ABSTRACTCommunal land-based resources are an essential source of livelihood in the rural economy of Ethiopia. In particular, the dependence of the landless people on the direct use of communal natural resources for their livelihoods jeopardizes both the resources they depend on and economic opportunities. To overcome such challenges, conservation of communal natural resources through collective action while addressing the food security problem has been described as one of the most appropriate resource management approaches. Thus, this paper explores how the livelihood strategies of landless people influence their willingness to participate in the conservation of natural resources. The study was conducted in five administrative districts in the Tigray region of northern Ethiopia. The findings of this paper are based on the cross-sectional data collected through structured questionnaires from 324 randomly selected landless households. This study extends the previous analyses by introducing a new method of analytical tool, particularly in modeling rural people’s willingness to participate in conservation. The results of ordered probit regression show that a higher level of willingness to conserve natural resources is observed if the household has access to farmland and harness resources generated in protected lands but with no access to artisanal mining and quarries. The study hence concludes that granting landless rural people access to farming activities and allowing them to reap economic benefits generated in protected lands promotes their participation in the conservation of natural resources.

Abstract The mining of genomes from non-cultivated microorganisms using metagenomics is a powerful tool to discover novel proteins and other valuable biomolecules. However, function-based metagenome searches are often limited by the time-consuming expression of the active proteins in various heterologous host systems. We here report the initial characterization of novel single-subunit bacteriophage RNA polymerase, EM1 RNAP, identified from a metagenome data set obtained from an elephant dung microbiome. EM1 RNAP and its promoter sequence are distantly related to T7 RNA polymerase. Using EM1 RNAP and a translation-competent Escherichia coli extract, we have developed an efficient medium-throughput pipeline and protocol allowing the expression of metagenome-derived genes and the production of proteins in cell-free system is sufficient for the initial testing of the predicted activities. Here, we have successfully identified and verified 12 enzymes acting on bis(2-hydroxyethyl) terephthalate (BHET) in a completely clone-free approach and proposed an in vitro high-throughput metagenomic screening method.

Visceral leishmaniasis (VL) is a disease caused by Leishmania parasites. While predominantly transmitted by sandflies, cases of VL transmitted through blood transfusion have been reported, particularly in immunocompromised recipients. Although Leishmania parasites have been found in blood donors in some VL endemic areas, this has never been studied in East-Africa, where HIV prevalence is relatively high. We established the prevalence of asymptomatic Leishmania infection and associated socio-demographic factors among blood donors presenting at two blood bank sites (Metema and Gondar) in northwest Ethiopia between June and December 2020. Metema is located in a VL-endemic area; Gondar has historically been considered VL non-endemic but as an outbreak of VL has occurred around Gondar, it was defined as previously VL non-endemic. Blood samples were tested by the rK39 rapid diagnostic test (RDT), rK39 ELISA, direct agglutination test (DAT) and qPCR targeting kinetoplast DNA (kDNA). Asymptomatic infection was defined as positive by any of these tests in a healthy person. A total of 426 voluntary blood donors were included. The median age was 22 years (IQR, 19-28 years); 59% were male and 81% resided in urban areas. Only one participant had a history of VL and three had a family history of VL. Asymptomatic infection was detected in 15.0% (n = 32/213) in Metema and 4.2% (n = 9/213) in Gondar. The rK39 ELISA was positive in 5.4% (n = 23/426), the rK39 RDT in 2.6% (11/426), PCR in 2.6% (11/420) and DAT in 0.5% (2/426). There were six individuals with two positive tests: one positive on rK39 RDT and PCR and five positive on rK39 RDT and ELISA. The prevalence of asymptomatic infection was higher in Metema (VL-endemic) and males but was not associated with age, a history of VL amongst family members or living in a rural area. Antibodies against Leishmania and parasite DNA was detected in a substantial number of blood donors. Future research should be directed at better defining the risk to recipients, including parasite viability studies and longitudinal studies amongst recipients.

Children of migrants in Australia are disproportionally affected by overweight/obesity. Their parents, however, are likely to put little effort into lifestyle changes if unable to recognise their children's suboptimal bodyweight. We examined the potential impact of migrant parents' bodyweight perception on their children's bodyweight over time and whether the region-of-birth of parents and acculturation to the host nation's way of life moderated the relationship, as very little is known about these in the Australian context. We analysed a sample of 2046 children of migrant parents drawn from 8 waves of population-based cohort data, the Longitudinal Study of Australian Children, capturing their lived experience from ages 2 to 17. After controlling for child, parent, family, and neighbourhood factors influencing children's bodyweight, multilevel models showed higher children's bodyweight in subsequent waves if their parents perceived children's bodyweight as lower than their actual bodyweight (i.e., underestimation). However, the rate of increase in children's bodyweight attenuated over time. The effect of migrant parents' underestimation on children's subsequent bodyweight differed by region-of-birth, with higher children's bodyweight in successive waves if their parents were from the Americas, compared to migrant parents from North/West Europe. Parents' acculturation, however, did not have a discernible effect. Although migrant parents' bodyweight perception of their children's bodyweight status influenced children's bodyweight in subsequent waves, this factor was not enough to explain the extent of disparities in children's bodyweight observed in the Australian migrant population. Further research is needed to assess the effects of other types of perception (such as perceptions of healthy weight and physical exercise) on bodyweight disparities in children of migrants.

The under-5 mortality rate is a commonly used indicator of population health and socioeconomic status worldwide. However, as in most low- and middle-income countries settings, deaths among children under-5 and in any age group in Ethiopia remain underreported and fragmented. We aimed to systematically estimate neonatal, infant, and under-5 mortality trends, identify underlying causes, and make subnational (regional and chartered cities) comparisons between 1990 and 2019. We used the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD 2019) to estimate three key under-5 mortality indicators—the probability of death between the date of birth and 28 days (neonatal mortality rate, NMR), the date of birth and 1 year (infant mortality rate, IMR), and the date of birth and 5 years (under-5 mortality rate, U5MR). The causes of death by age groups, sex, and year were estimated using Cause of Death Ensemble modelling (CODEm). Specifically, this involved a multi-stage process that includes a non-linear mixed-effects model, source bias correction, spatiotemporal smoothing, and a Gaussian process regression to synthesise mortality estimates by age, sex, location, and year. In 2019, an estimated 190,173 (95% uncertainty interval 149,789–242,575) under-5 deaths occurred in Ethiopia. Nearly three-quarters (74%) of under-5 deaths in 2019 were within the first year of life, and over half (52%) in the first 28 days. The overall U5MR, IMR, and NMR in the country were estimated to be 52.4 (44.7–62.4), 41.5 (35.2–50.0), and 26.6 (22.6–31.5) deaths per 1000 livebirths, respectively, with substantial variations between administrative regions. Over three-quarters of under-5 deaths in 2019 were due to five leading causes, namely neonatal disorders (40.7%), diarrhoeal diseases (13.2%), lower respiratory infections (10.3%), congenital birth defects (7.0%), and malaria (6.0%). During the same period, neonatal disorders alone accounted for about 76.4% (70.2–79.6) of neonatal and 54.7% (51.9–57.2) of infant deaths in Ethiopia. While all regional states in Ethiopia have experienced a decline in under-5, infant, and neonatal mortality rates in the past three decades, the rate of change was not large enough to meet the targets of the Sustainable Development Goals (SDGs). Inter-regional disparities in under 5 mortality also remain significant, with the biggest differences being in the neonatal period. A concerted effort is required to improve neonatal survival and lessen regional disparity, which may require strengthening essential obstetric and neonatal care services, among others. Our study also highlights the urgent need for primary studies to improve the accuracy of regional estimates in Ethiopia, particularly in pastoralist regions.

It is often reported that young people in Africa, the Middle East and North African regions are stuck in situations of ‘waithood’, unable to progress to full adulthood. Utilising a series of innovative research methodologies that included life history interviews, surveys, media training and qualitative interviews, the research project’s aim was the co-production of data, in order to delve into the housing and work nexus in two non-central locations in Ethiopia and South Africa. The variety of mixed methods that were used yielded a depth of engagement and allowed the researchers to deepen and nuance ideas of waithood and stuckness. The rich and varied data showed how young people move through moments of stuckness and moments of movement, and that some movement is possible even when faced with difficult and sometimes overwhelming structural challenges. It also demonstrated how co-produced research can assist young people in moving forward and countering the experience of stuckness and waithood.

Metal–polyphenol networks (MPNs) are being used as versatile coatings for regulating membrane surface chemistry and for the formation of thin separation layers. The intrinsic nature of plant polyphenols and their coordination with transition metal ions provide a green synthesis procedure of thin films, which enhance membrane hydrophilicity and fouling resistance. MPNs have been used to fabricate tailorable coating layers for high-performance membranes desirable for a wide range of applications. Here, we present the recent progress of the use of MPNs in membrane materials and processes with a special focus on the important roles of tannic acid–metal ion (TA-Mn+) coordination for thin film formation. This review introduces the most recent advances in the fabrication techniques and the application areas of TA-Mn+ containing membranes. In addition, this paper outlines the latest research progress of the TA–metal ion containing membranes and summarizes the role of MPNs in membrane performance. The impact of fabrication parameters, as well as the stability of the synthesized films, is discussed. Finally, the remaining challenges that the field still faces and potential future opportunities are illustrated.

Background: In Ethiopia, 79 million people live in soil transmitted helminths endemic areas. The Ethiopia established a National goal to eradicate STH transmission by 2025. To meet that goal, it is imperative that data is acquired on community helminth infection risk. This study examined the prevalence of STH and risk factors for infection in vegetable farmers working on Akaki River Bank, Addis Ababa, Ethiopia. Methods: A cross-sectional study was conducted between November 7, 2022, and June 2023. A stratified random sampling was used to select farming households. Two hundred and sixteen farmers were enrolled in the study. Data on socio-demographic, WASH, wastewater irrigation related factors were collected by trained data collectors using a structured questionnaire. Kato-Katz concentration was utilized to detect STH. The data were entered using EpiData 3.1 and analyzed with Stata 14.0, using p-values less than 0.05 to identify significant factors. Logistic regression was used to identify independent risk factors for infection. Results: The prevalence of STH was 22.2% (95% CI = 13.6-27.9%), with Ascaris lumbricoides being the most common (11.1%), followed by hookworm (7.4%), and Trichuris trichiura (3.7%). Low income levels (AOR = 1.85, 95% CI = 1.25–5.99), lack of handwashing before eating (AOR = 2.25, 95% CI = 1.58 − 11.3), absence of fingernails cleanliness (AOR = 1.97, 95% CI = 1.74–39.5), not wearing shoes at work (AOR = 3.4, 95% CI = 2.98–82.2), touching the face with dirty hands (AOR = 2.9, 95% CI = 0.68–28.2), washing vegetables with irrigation wastewater (AOR = 2.1, 95% CI = 1.95–45.2), and not wearing protective clothing during farming activities (AOR = 2.99, 95% CI = 1.58 − 22.4) were the significant risk factors for infection with STH. Conclusion: Of the farming communities examined in this study, one of the five was found to be infected with soil transmitted helminth. This research has shown clear risk factors for STH infection including: lack of personal hygiene practices, insufficient sanitation access, and limited use of protective equipment. To achieve the national goal, there is a need for farming communities to understand preventative risks of infection, improve WASH (Water access, sanitation and hygine) practices, WASH access, protective equipment, and health education. [ABSTRACT FROM AUTHOR]

BackgroundThe Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context.MethodsWe used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors-the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI).FindingsBetween 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6-58·8) of global deaths and 41·2% (39·8-42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa.InterpretationDeclines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden.FundingBill & Melinda Gates Foundation.

Abstract Obesity significantly impairs breathing during exercise. The aim was to determine, in male obese adolescents (OB), the effects of acute respiratory muscle unloading, obtained by switching the inspired gas from ambient air (AIR) to a normoxic helium + oxygen gas mixture (HeO2) (AIR → HeO2) during moderate [below gas exchange threshold (GET)] and heavy [above GET] constant work rate cycling. Ten OB [age 16.0 ± 2.0 years (mean ± SD); body mass index (BMI) 38.9 ± 6.1 kg/m2] and ten normal-weight age-matched controls (CTRL) inspired AIR for the entire exercise task, or underwent AIR → HeO2 when they were approaching volitional exhaustion. In OB time to exhaustion (TTE) significantly increased in AIR → HeO2 vs. AIR during moderate [1524 ± 480 s vs. 1308 ± 408 (P = 0.024)] and during heavy [570 ± 306 s vs. 408 ± 150 (P = 0.0154)] exercise. During moderate exercise all CTRL completed the 40-min task. During heavy exercise no significant differences were observed in CTRL for TTE (582 ± 348 s [AIR → HeO2] vs. 588 ± 252 [AIR]). In OB, but not in CTRL, acute unloading of respiratory muscles increased TTE during both moderate- and heavy-exercise. In OB, but not in CTRL, respiratory factors limit exercise tolerance during both moderate and heavy exercise.