Linking weather data, satellite imagery and field observations to household food production and child undernutrition: an exploratory study in Burkina Faso

Worldwide, 50 million children under five are acutely malnourished, while 16 million amongst them suffer from severe wasting. Chronic malnutrition is more common and accounts for an estimated 159 million children, meaning that approximately 23.8% of all children under five worldwide are stunted. The proportion of stunted children has decreased worldwide between 1990 (39.6%) and 2014 (23.8%), but the progress has been unequal. While Asia as a whole reduced stunting by half (-47.0%) between 1990 and 2014, there are still 78 million stunted children in South Asia alone. Unlike Asia, the African continent has reduced stunting by just one quarter (24.0%). In contrast, the absolute number of stunted children in Africa has still increased, from 47 million in 1990, to 58 million in 2014. Under-nutrition is caused by a complex web of interdependent environmental/climatic, agricultural and socio-economic factors. Climate change has recently been identified as a major risk factor for childhood undernutrition. However, the scientific evidence base for this is weak. No study has so far simultaneously combined of the well-known drivers of undernutrition with climate change while being grounded in one population in one-time and in one location. Such studies are prerequisite for the relative attribution of the various risk factors, including climate chance, as causes of childhood undernutrition. In this exploratory study, methods from multiple sectors were applied to 20 randomly selected households in Bourasso in rural Burkina Faso, where more than 80% of the population are subsistence farmers, i.e. live off their fields. Well tested methods, such as household-level agricultural and nutritional surveys, anthropometric measurement of undernutrition with innovative methods, measuring household level-crop yields, were combined. This was done by participatory mapping of each household’s plots. Remote sensing algorithms were applied to RapidEye satellite scenes covering the study area in order to map the actual cultivated area and to derive qualitative harvest estimates for the surveyed micro-fields. Weather data were obtained from a research meteorological field station, about 20 km away from Bourasso. In addition to bringing field methods from different sectors together through the lens of a household, one further advanced method was integrated: The linkage between each household plot limits and their integration into the satellite scene making it possible to estimate crop yields at the plot level for each household and linking this to the nutritional status of that specific household. Thus the exploratory study produced the following results: High-resolution remote sensing data can assist studies on malnutrition in Burkina Faso; RapidEye is a promising data source in regard to the spatial resolution for micro-field assessments; The strong inter-annual variation of malnutrition is suggestive that climate is a casual factor in the absence of other explanatory factors (political unrest, price shocks of inputs, epidemics). Population-based studies replicating the described multi-sectoral toolbox should be upscaled to larger sample sizes and longer observational time series. This could contribute to generating crucial climate health impact functions, in this case for malnutrition

an overview of the MHONGOOSE survey: Observing nearby galaxies with MeerKAT

© Copyright owned by the author(s). MHONGOOSE is a deep survey of the neutral hydrogen distribution in a representative sample of 30 nearby disk and dwarf galaxies with H I masses from ∼ 106 to ∼ 1011 M, and luminosities from MR ∼ 12 to MR ∼ −22. The sample is selected to uniformly cover the available range in log(MHI). Our extremely deep observations, down to H I column density limits of well below 1018 cm−2 — or a few hundred times fainter than the typical H I disks in galaxies — will directly detect the effects of cold accretion from the intergalactic medium and the links with the cosmic web. These observations will be the first ever to probe the very low-column density neutral gas in galaxies at these high resolutions. Combination with data at other wavelengths, most of it already available, will enable accurate modeling of the properties and evolution of the mass components in these galaxies and link these with the effects of environment, dark matter distribution, and other fundamental properties such as halo mass and angular momentum. MHONGOOSE can already start addressing some of the SKA-1 science goals and will provide a comprehensive inventory of the processes driving the transformation and evolution of galaxies in the nearby universe at high resolution and over 5 orders of magnitude in column density. It will be a Nearby Galaxies Legacy Survey that will be unsurpassed until the advent of the SKA, and can serve as a highly visible, lasting statement of MeerKAT’s capabilities

Prostration and the prognosis of death in African children with severe malaria

Objectives: Malaria is still one of the main reasons for hospitalization in children living in sub-Saharan Africa. Rapid risk stratification at admission is essential for optimal medical care and improved prognosis. Whereas coma, deep breathing, and, to a lesser degree, severe anemia are established predictors of malaria-related death, the value of assessing prostration for risk stratification is less certain. Methods: Here we used a retrospective multi-center analysis comprising over 33,000 hospitalized children from four large studies, including two observational studies from the Severe Malaria in African Children network, a randomized controlled treatment study, and the phase-3-clinical RTS,S-malaria vaccine trial, to evaluate known risk factors of mortality and with a specific emphasis on the role of prostration. Results: Despite comparable age profiles of the participants, we found significant inter- and intra-study variation in the incidence of fatal malaria as well as in the derived risk ratios associated with the four risk factors: coma, deep breathing, anemia, and prostration. Despite pronounced variations, prostration was significantly associated with an increased risk of mortality (P <0.001) and its consideration resulted in improved predictive performance, both in a multivariate model and a univariate model based on the Lambaréné Organ Dysfunction Score. Conclusion: Prostration is an important clinical criterion to determine severe pediatric malaria with possible fatal outcomes

Major reduction of malaria morbidity with combined vitamin A and zinc supplementation in young children in Burkina Faso: a randomized double blind trial

BACKGROUND: Vitamin A and zinc are crucial for normal immune function, and may play a synergistic role for reducing the risk of infection including malaria caused by Plasmodium falciparum. METHODS: A randomized, double-blind, placebo-controlled trial of a single dose of 200 000 IU of vitamin A with daily zinc supplementation was done in children of Sourkoudougou village, Burkina Faso. Children aged from 6 to 72 months were randomized to receive a single dose of 200 000 IU of vitamin A plus 10 mg elemental zinc, six days a week (n = 74) or placebo (n = 74) for a period of six months. Cross-sectional surveys were conducted at the beginning and the end of the study, and children were evaluated daily for fever. Microscopic examination of blood smear was done in the case of fever (temperature > or =37.5 degrees C) for malaria parasite detection. RESULTS: At the end of the study we observed a significant decrease in the prevalence malaria in the supplemented group (34%) compared to the placebo group (3.5%) (p < 0.001). Malaria episodes were lower in the supplemented group (p = 0.029), with a 30.2% reduction of malaria cases (p = 0.025). Time to first malaria episode was longer in the supplemented group (p = 0.015). The supplemented group also had 22% fewer fever episodes than the placebo group (p = 0.030). CONCLUSION: These results suggest that combined vitamin A plus zinc supplementation reduces the risk of fever and clinical malaria episodes among children, and thus may play a key role in malaria control strategies for children in Africa

INSIGHTS INTO THE INTERPLAY BETWEEN KIR GENE FREQUENCIES AND CHRONIC HBV INFECTION IN BURKINA FASO

Background/Objective: The receptors of natural killer cells "Killer Cell Immunoglobulin-Like Receptor" (KIR) regulate the activity of Natural killer cells in the innate response against viral infections. To date there is no accurate method to identify high risk groups for cirrhosis and HCC in Sub-Saharan Africa. Therefore, this investigation was undertaken to assess the association between KIR genes frequencies and chronic infection HBV infection in Burkina Faso’s population. Methods: Chronic HBV carriers and healthy patients were selected for this study. The viral load for HBV were performed to confirm the serological status for HBV of the studied cohort. In addition, SSP-PCR was used to characterize the frequencies of KIR genes. Results: The study suggested that inhibitory genes KIR2DL2, KIR2DL3 and activator gene KIR2DS2 (p˂0.001 for all and OR = 2.82; 2.48 and 3.84 respectively) might be associated with chronic stages of HBV infection.  While inhibitory genes KIR3DL1 (p = 0.0018 OR = 0.49), KIR3DL2 (p = 0.005 OR = 0.40), the activator gene KIR2DS1 (p = 0.014 OR = 0.47) and the pseudo gene KIR2DP1 (p = 0.011 OR = 0.49) could be associated with immunity against HBV infection. Patients who carried the KIR3DL2 gene had a high HBV viral load compared to the rest of the study population. Conclusion: Our data showed an evidence of correlation between the propensity of developing chronic HBV infection and certain KIR gene frequencies and that KIR3DL1, KIR3DL2, KIR2DS1 and KIR2DP1 might confer a protective status against chronic HBV infection in Burkina Faso’s patients

New Antenatal Model in Africa and India (NAMAI) study: implementation research to improve antenatal care using WHO recommendations

Background: In 2020, an estimated 287 000 women died globally from pregnancy‐related causes and 2 million babies were stillborn. Many of these outcomes can be prevented by quality healthcare during pregnancy and childbirth. Within the continuum of maternal health, antenatal care (ANC) is a key moment in terms of contact with the health system, yet it remains an underutilized platform. This paper describes the protocol for a study conducted in collaboration with Ministries of Health and country research partners that aims to employ implementation science to systematically introduce and test the applicability of the adapted WHO ANC package in selected sites across four countries. Methods: Study design is a mixed methods stepped-wedge cluster randomized implementation trial with a nested cohort component (in India and Burkina Faso). The intervention is composed of two layers: (i) the country- (or state)-specific ANC package, including evidence-based interventions to improve maternal and newborn health outcomes, and (ii) the co-interventions (or implementation strategies) to help delivery and uptake of the adapted ANC package. Using COM-B model, co-interventions support behaviour change among health workers and pregnant women by (1) training health workers on the adapted ANC package and ultrasound (except in India), (2) providing supplies, (3) conducting mentoring and supervision and (4) implementing community mobilization strategies. In Rwanda and Zambia, a fifth strategy includes a digital health intervention. Qualitative data will be gathered from health workers, women and their families, to gauge acceptability of the adapted ANC package and its components, as well as experience of care. The implementation of the adapted ANC package of interventions, and their related costs, will be documented to understand to what extent the co-interventions were performed as intended, allowing for iteration. Discussion: Results from this study aim to build the global evidence base on how to implement quality ANC across different settings and inform pathways to scale, which will ultimately lead to stronger health systems with better maternal and perinatal outcomes. On the basis of the study results, governments will be able to adopt and plan for national scale-up, aiming to improve ANC nationally. This evidence will inform global guidance. Trial registration number: ISRCTN, ISRCTN16610902. Registered 27 May 2022. https://www.isrctn.com/ISRCTN16610902

Poor cardiovascular health is associated with subclinical atherosclerosis in apparently healthy sub-Saharan African populations: an H3Africa AWI-Gen study

Background: The cardiovascular health index (CVHI) introduced by the American Heart Association is a valid, accessible, simple, and translatable metric for monitoring cardiovascular health in a population. Components of the CVHI include the following seven cardiovascular risk factors (often captured as life’s simple 7): smoking, dietary intake, physical activity, body mass index, blood pressure, glucose, and total cholesterol. We sought to expand the evidence for its utility to under-studied populations in sub-Saharan Africa, by determining its association with common carotid intima-media thickness (CIMT). Methods: We conducted a cross-sectional study involving 9011 participants drawn from Burkina Faso, Ghana, Kenya, and South Africa. We assessed established classical cardiovascular risk factors and measured carotid intima-media thickness of the left and right common carotid arteries using B-mode ultrasonography. Adjusted multilevel mixed-effect linear regression was used to determine the association of CVHI with common CIMT. In the combined population, an individual participant data meta-analyses random-effects was used to conduct pooled comparative sub-group analyses for differences between countries, sex, and socio-economic status. Results: The mean age of the study population was 51 ± 7 years and 51% were women, with a mean common CIMT of 637 ± 117 μm and CVHI score of 10.3 ± 2.0. Inverse associations were found between CVHI and common CIMT (β-coefficients [95% confidence interval]: Burkina Faso, − 6.51 [− 9.83, − 3.20] μm; Ghana, − 5.42 [− 8.90, − 1.95]; Kenya, − 6.58 [− 9.05, − 4.10]; and South Africa, − 7.85 [− 9.65, − 6.05]). Inverse relations were observed for women (− 4.44 [− 6.23, − 2.65]) and men (− 6.27 [− 7.91, − 4.64]) in the pooled sample. Smoking (p < 0.001), physical activity (p < 0.001), and hyperglycemia (p < 0.001) were related to CIMT in women only, while blood pressure and obesity were related to CIMT in both women and men (p < 0.001). Conclusion: This large pan-African population study demonstrates that CVHI is a strong marker of subclinical atherosclerosis, measured by common CIMT and importantly demonstrates that primary prevention of atherosclerotic cardiovascular disease in this understudied population should target physical activity, smoking, obesity, hypertension, and hyperglycemia

An overview of the MHONGOOSE survey: Observing nearby galaxies with MeerKAT

MHONGOOSE is a deep survey of the neutral hydrogen distribution in a representative sample of 30 nearby disk and dwarf galaxies with HI masses from 10^6 to ~10^{11} M_sun, and luminosities from M_R ~ -12 to M_R ~ -22. The sample is selected to uniformly cover the available range in log(M_HI). Our extremely deep observations, down to HI column density limits of well below 10^{18} cm^{-2} - or a few hundred times fainter than the typical HI disks in galaxies - will directly detect the effects of cold accretion from the intergalactic medium and the links with the cosmic web. These observations will be the first ever to probe the very low-column density neutral gas in galaxies at these high resolutions. Combination with data at other wavelengths, most of it already available, will enable accurate modelling of the properties and evolution of the mass components in these galaxies and link these with the effects of environment, dark matter distribution, and other fundamental properties such as halo mass and angular momentum. MHONGOOSE can already start addressing some of the SKA-1 science goals and will provide a comprehensive inventory of the processes driving the transformation and evolution of galaxies in the nearby universe at high resolution and over 5 orders of magnitude in column density. It will be a Nearby Galaxies Legacy Survey that will be unsurpassed until the advent of the SKA, and can serve as a highly visible, lasting statement of MeerKAT's capabilities

SKA Science Data Challenge 2: analysis and results

The Square Kilometre Array Observatory (SKAO) will explore the radio sky to new depths in order to conduct transformational science. SKAO data products made available to astronomers will be correspondingly large and complex, requiring the application of advanced analysis techniques to extract key science findings. To this end, SKAO is conducting a series of Science Data Challenges, each designed to familiarise the scientific community with SKAO data and to drive the development of new analysis techniques. We present the results from Science Data Challenge 2 (SDC2), which invited participants to find and characterise 233245 neutral hydrogen (Hi) sources in a simulated data product representing a 2000~h SKA MID spectral line observation from redshifts 0.25 to 0.5. Through the generous support of eight international supercomputing facilities, participants were able to undertake the Challenge using dedicated computational resources. Alongside the main challenge, `reproducibility awards' were made in recognition of those pipelines which demonstrated Open Science best practice. The Challenge saw over 100 participants develop a range of new and existing techniques, with results that highlight the strengths of multidisciplinary and collaborative effort. The winning strategy -- which combined predictions from two independent machine learning techniques to yield a 20 percent improvement in overall performance -- underscores one of the main Challenge outcomes: that of method complementarity. It is likely that the combination of methods in a so-called ensemble approach will be key to exploiting very large astronomical datasets.Comment: Under review by MNRAS; 28 pages, 16 figure