Socioecologically informed use of remote sensing data to predict rural household poverty.

Tracking the progress of the Sustainable Development Goals (SDGs) and targeting interventions requires frequent, up-to-date data on social, economic, and ecosystem conditions. Monitoring socioeconomic targets using household survey data would require census enumeration combined with annual sample surveys on consumption and socioeconomic trends. Such surveys could cost up to $253 billion globally during the lifetime of the SDGs, almost double the global development assistance budget for 2013. We examine the role that satellite data could have in monitoring progress toward reducing poverty in rural areas by asking two questions: (i) Can household wealth be predicted from satellite data? (ii) Can a socioecologically informed multilevel treatment of the satellite data increase the ability to explain variance in household wealth? We found that satellite data explained up to 62% of the variation in household level wealth in a rural area of western Kenya when using a multilevel approach. This was a 10% increase compared with previously used single-level methods, which do not consider details of spatial landscape use. The size of buildings within a family compound (homestead), amount of bare agricultural land surrounding a homestead, amount of bare ground inside the homestead, and the length of growing season were important predictor variables. Our results show that a multilevel approach linking satellite and household data allows improved mapping of homestead characteristics, local land uses, and agricultural productivity, illustrating that satellite data can support the data revolution required for monitoring SDGs, especially those related to poverty and leaving no one behind.

Assessing nutritional diversity of cropping systems in African villages.

BACKGROUND: In Sub-Saharan Africa, 40% of children under five years in age are chronically undernourished. As new investments and attention galvanize action on African agriculture to reduce hunger, there is an urgent need for metrics that monitor agricultural progress beyond calories produced per capita and address nutritional diversity essential for human health. In this study we demonstrate how an ecological tool, functional diversity (FD), has potential to address this need and provide new insights on nutritional diversity of cropping systems in rural Africa. METHODS AND FINDINGS: Data on edible plant species diversity, food security and diet diversity were collected for 170 farms in three rural settings in Sub-Saharan Africa. Nutritional FD metrics were calculated based on farm species composition and species nutritional composition. Iron and vitamin A deficiency were determined from blood samples of 90 adult women. Nutritional FD metrics summarized the diversity of nutrients provided by the farm and showed variability between farms and villages. Regression of nutritional FD against species richness and expected FD enabled identification of key species that add nutrient diversity to the system and assessed the degree of redundancy for nutrient traits. Nutritional FD analysis demonstrated that depending on the original composition of species on farm or village, adding or removing individual species can have radically different outcomes for nutritional diversity. While correlations between nutritional FD, food and nutrition indicators were not significant at household level, associations between these variables were observed at village level. CONCLUSION: This study provides novel metrics to address nutritional diversity in farming systems and examples of how these metrics can help guide agricultural interventions towards adequate nutrient diversity. New hypotheses on the link between agro-diversity, food security and human nutrition are generated and strategies for future research are suggested calling for integration of agriculture, ecology, nutrition, and socio-economics.

High rates of AIDS-related mortality among older adults in rural Kenya.

BACKGROUND: Health challenges faced by older people in developing countries are often neglected amidst a wide range of competing priorities. This is evident in the HIV field where the upper age limit for reporting HIV prevalence remains 49 years. However, the long latency period for HIV infection, and the fact that older people continue to be sexually active, suggests that HIV and AIDS are likely to affect older people. To better understand this, we studied mortality due to AIDS in people aged 50 and older in an area of rural Kenya with high rates of HIV infection. METHODS: A community health worker-administered verbal autopsy system was introduced in Nyanza Province, encompassing 63,500 people. Algorithms were used to determine cause of death. RESULTS: A total of 1228 deaths were recorded during the study period; 368 deaths occurred in people aged 50 years and older. AIDS was the single most common cause of death, causing 27% of all deaths. AIDS continued to be the main cause of death up to age 70 years, causing 34% of deaths in people aged 50-59 years and 23% of deaths in people aged 60-69 years. CONCLUSIONS: AIDS remains the principle cause of death among older people in Nyanza Province in western Kenya up until the age of 70 years. Greater efforts are needed to integrate older people into the HIV response and to better understand the specific vulnerabilities and challenges faced by this group.

Identifying potential synergies and trade-offs for meeting food security and climate change objectives in sub-Saharan Africa.

Potential interactions between food production and climate mitigation are explored for two situations in sub-Saharan Africa, where deforestation and land degradation overlap with hunger and poverty. Three agriculture intensification scenarios for supplying nitrogen to increase crop production (mineral fertilizer, herbaceous legume cover crops--green manures--and agroforestry--legume improved tree fallows) are compared to baseline food production, land requirements to meet basic caloric requirements, and greenhouse gas emissions. At low population densities and high land availability, food security and climate mitigation goals are met with all intensification scenarios, resulting in surplus crop area for reforestation. In contrast, for high population density and small farm sizes, attaining food security and reducing greenhouse gas emissions require mineral fertilizers to make land available for reforestation; green manure or improved tree fallows do not provide sufficient increases in yields to permit reforestation. Tree fallows sequester significant carbon on cropland, but green manures result in net carbon dioxide equivalent emissions because of nitrogen additions. Although these results are encouraging, agricultural intensification in sub-Saharan Africa with mineral fertilizers, green manures, or improved tree fallows will remain low without policies that address access, costs, and lack of incentives. Carbon financing for small-holder agriculture could increase the likelihood of success of Reducing Emissions from Deforestation and Forest Degradation in Developing Countries programs and climate change mitigation but also promote food security in the region.

Feasibility, acceptability and cost of home-based HIV testing in rural Kenya.

OBJECTIVE: To demonstrate the feasibility, acceptability and cost of home-based HIV testing and to examine the applicability of the model to high HIV prevalence settings. METHODS: Quantitative, qualitative and cost data were collected during a home-based HIV testing program in a high-prevalence rural area of Kenya; data on age, gender and marital status along with HIV test results were collected. This was complemented with qualitative research including key informant interviews with counselors and program managers to highlight experiences and challenges. Direct costs of the interventions were estimated through the review of budgets and monthly expenditure sheets. RESULTS: Of 3180 15-49-year olds exposed to a community awareness campaign, 2033 (63.9%) agreed to be visited by counselors, of whom 1984 (97.6%) agreed to be tested and receive the results. Adult HIV prevalence was 8.2% and married women were 4.8 times more likely to be HIV-positive than those never married. Counselors reported feeling welcomed and noted the enthusiasm of the community towards testing. The total cost of the exercise was $17,569. The program cost was $2.60 for each of the 6750 community members, $5.88 for each person tested, and $84 per positive case detected. CONCLUSION: This study suggests that home-based HIV testing is feasible with high uptake, and has the potential to substantially expand access to HIV testing services. There is a strong economic case for the extension of such a screening program to other communities.

The African Millennium Villages.

We describe the concept, strategy, and initial results of the Millennium Villages Project and implications regarding sustainability and scalability. Our underlying hypothesis is that the interacting crises of agriculture, health, and infrastructure in rural Africa can be overcome through targeted public-sector investments to raise rural productivity and, thereby, to increased private-sector saving and investments. This is carried out by empowering impoverished communities with science-based interventions. Seventy-eight Millennium Villages have been initiated in 12 sites in 10 African countries, each representing a major agro-ecological zone. In early results, the research villages in Kenya, Ethiopia, and Malawi have reduced malaria prevalence, met caloric requirements, generated crop surpluses, enabled school feeding programs, and provided cash earnings for farm families.

Econutrition: implementation models from the Millennium Villages Project in Africa.

Econutrition integrates environmental health and human health, with a particular focus on the interactions among the fields of agriculture, ecology, and human nutrition. Soil loss and degradation and human undernutrition are major barriers to economic development in Africa. A primary aim of the Millennium Villages Project in Africa is to meet the Millennium Development Goals by integrated multisectoral interventions in health and nutrition, agriculture, and environmental sustainability in hunger and poverty hot spots in Africa. Econutrition is only one example of how interdisciplinary approaches are not only critical to alleviating extreme poverty but also fundamental to linking basic science understanding in multiple areas. Human health and agricultural productivity gain, and the costs of the gains are lowered, when we take the opportunity to apply different disciplines through cross-sectoral, thematically linked interventions.