Caractères cliniques et épidémiologiques de la dengue 2 au Sénégal

Les auteurs rappellent les faits historiques, cliniques et épidémiologiques concernant l'infection par les virus de la dengue en Afrique. Ils énumèrent les lieux, les hôtes et les circonstances de l'isolement de différentes souches africaines et rappellent le cycle sauvage du virus dengue 2 au Sénégal. L'isolement de deux souches humaines, pendant l'épizootie de 1990, est en faveur d'un cycle selvatique. Il s'agit en effet des premiers cas humains concomitants d'une épizootie au Sénégal. Les observations cliniques de ces deux cas sont celles d'une arbovirose mineure, sans syndrome de choc ni manifestations hémorragiques, soulignant la pathogénicité atténuée du virus dengue 2 au Sénégal comme dans les autres pays d'Afrique. De récents travaux d'épidémiologie moléculaire ont mis en évidence des caractères génotypiques particuliers de certaines souches africaines par rapport à celles rencontrées dans les régions Pacifique ou Caraïbes. (Résumé d'auteur

Response of Common Bean (Phaseolus vulgaris L.) to Endomycorrhizal Inoculation under Different Phosphorus Application Levels in South-Kivu, Eastern DRC

Arbuscular mycorrhizal fungi (AMF) have been reported to increase yield and phosphorus (P) uptake. However, it is still unclear how the common bean responds to mycorrhizal inoculation when there is a phosphate supply. This research focused on finding out how bean performance will be affected by mycorrhizal inoculation and increasing P dosages in order to reduce phosphate input. The study was conducted during the A 2021 cropping season in Kabare, while a split-plot design was used to compare two levels of inoculation and increasing phosphorus doses. Rhizophagus irregularis inoculation significantly improved mycorrhizal colonization, biomass, yield, and harvest index of beans at 0 and 30 kg P ha-1. Bean plants inoculated with R. irregularis performed better in terms of biomass, yield, and harvest index at 30 kg P ha-1 than non-inoculated and inoculated plants at 60 and 120 kg P ha-1, indicating the potential of AMF in lowering phosphate input. Phosphorus levels of 60 and 120 kg P ha-1 significantly decreased mycorrhizal infection, indicating the impact of inorganic P on the mycorrhizal symbiosis. In the ferralitic soils of Kashusha, mycorrhizal inoculation with R. irregularis may be a key tool for increasing bean production and ensuring phosphate fertilizer savings

Neglected and underutilized crop species in Kabare and Walungu territories, Eastern D.R. Congo: Identification, uses and socio-economic importance

peer reviewedNeglected and underutilized crop species (NUCS) are valuable sources of food and income for several rural households in the eastern Democratic Republic of Congo (DRC). A thorough understanding of their diversity, uses, socioeconomic roles, and factors for their neglect would be necessary for guiding promotion efforts. This study was conducted in two steps: (1) interviews with rural households involved in NUCS production and trade, and (2) greenhouse characterization of the two most popular NUCS ′ morphotypes, African nightshade and amaranth, from Walungu and Kabare territories, eastern DRC. About 19% of farmers of the entire study area were involved in NUCS production. We identified 22 and 23 NUCS used in Kabare and Walungu territories, respectively. These species belonged to 19 botanical families, among which Solanaceae (~24% in Walungu and ~11 in Kabare) and Fabaceae (8% in Walungu and 11% in Kabare) were the most dominant families. They were of different ranges: grasses and herbs (62%), shrubs (20%), thorns (2%), and trees (16%). These species were used whether for nutritional (60%), medicinal (7%), or both nutritional and medicinal values (33%). NUCS' market value was low, and thus, discouraged further investment in their farming. The seed delivery system was informal, dominated by farmer-saved seed, seed from local markets, and farmer seed exchange. Characterization experiment for the most popular leafy NUCS showed differences among collected morphotypes for most traits, with some local genotypes outperforming exogenous commercial varieties. Supply of quality seed, training of farmers on the most appropriate cropping system, processing technologies, increased consumer awareness, linking research to policy, and increasing market opportunities for smallholder farmers are strategies for promoting wide use of these crops in eastern DRC

Di-ammonium phosphate (DAP) and plant density improve grain yield, nodulation capacity, and profitability of peas (Pisum sativum L.) on ferralsols in eastern D.R. Congo

peer reviewedAbstractSustaining high crop yield and profitability on marginal soils, such as degraded ferralsols, calls for the use of adequate farming practices. In this study, we assessed for four cropping seasons the effect of di-ammonium phosphate (DAP) fertilizer application doses (100, 150, and 200 kg ha−1) and plant densities (100,000, 166,666, and 250,000 plants ha−1) on growth, yield, nodulation capacity, and profitability of two pea varieties (Adei and Rwanda) under degraded ferralsols in eastern Democratic Republic of Congo (DRC). Results showed that pea growth, yield, nodulation, and profitability were significantly affected by the DAP dose and the plant density. Application of 150 kg ha−1 of DAP improved pea yields from 730 to 1720 kg ha−1 and nodulation from 17 to 22 nodules per plant. The number of active nodules was positively correlated with total number of nodules, DAP doses, yield parameters, and plant height. High grain yield was recorded during the long rainy season (1400 kg ha−1) compared to the short one (930 kg ha−1). All DAP doses were profitable according to the agronomic efficiency (AE) and value–cost ratio (VCR) analyses. For improved and profitable pea production on degraded South-Kivu ferralsols, applying 150 kg ha−1 of DAP combined with low plant density are to be recommended and preferably in the long rainy season

Fortification with mushroom flour (Pleurotus ostreatus (Jacq.) P. Kumm) and substitution of wheat flour by cassava flour in bread-making: Nutritional and technical implications in eastern DR Congo

peer reviewedBackground: The import of wheat flour is the major driver for the high prices and low use of bakery products in nonproducing tropical countries such as the Democratic Republic of Congo (DRC). These products' high prices worsen the risk of malnutrition and food insecurity among rural and resource-poor populations. This study aimed at substituting the imported wheat flour with less expensive local cassava flour fortified with oyster mushroom flour in order to mitigate the nutritional crisis in the region. Methodology: Series of experiments were conducted by substituting wheat flour with cassava flour at proportions of 10-25% to find the optimal combination. In addition, oyster mushroom flour (2.5-10%) was added to the composite flour to compensate for nutrient deficiencies of cereals and tuber crops. The overall aim was to identify the optimal wheat-cassava-mushroom combination, improving the nutritional value of breads while keeping their physicochemical and organoleptic properties. Results: Results showed that 0-10% mushroom flour increased bread protein from 19.63 to 22.66%. Besides, 7.5% mushroom flour allowed rising the bread calories from 311.8 to 354.5 kcal, and the dry matter from 77.33 to 87.86%. The wheat substitution for cassava fortified with mushroom flour negatively affected the bread volume, color and taste (p < 0.001). However, other organoleptic features remained unchanged. The different breads were microbiologically stable for bacteria, but susceptible to fungal attacks. Conclusion: This study recommended 5-15-80% and 10-10-80% mushroom-cassava-wheat composite flour for better bakery results, good consistency and high protein and energy contents, for improving the nutritional status of populations in the tropical non-wheat producing regions such as DRC. Efforts are necessary to improve the taste and color of the mushroom-fortified bread to increase its uptake and competitiveness in the local markets

Gully erosion susceptibility mapping using four machine learning methods in Luzinzi watershed, eastern Democratic Republic of Congo

peer reviewedSoil erosion by gullying causes severe soil degradation, which in turn leads to severe socio-economic and environmental damages in tropical and subtropical regions. To mitigate these negative effects and guarantee sustainable management of natural resources, gullies must be prevented. Gully management strategies start by devising adequate assessment tools and identification of driving factors and control measures. To achieve this, machine learning methods are essential tools to assist in the identification of driving factors to implement site-specific control measures. This study aimed at assessing the effectiveness of four machine learning methods (Random Forest (RF), Maximum of Entropy (MaxEnt), Artificial Neural Network (ANN), and Boosted Regression Tree (BRT)) to identify gully's driving factors, and predict gully erosion susceptibility in the Luzinzi watershed, in eastern Democratic Republic of Congo (DRC)

Climate Change Effect on Water Use Efficiency under Selected Soil and Water Conservation Practices in the Ruzizi Catchment, Eastern D.R. Congo

peer reviewedConcerns have been raised on the effectiveness and sustainability of Soil and Water Conservation (SWC) practices as adaptation options to climate change and high intra– and inter–annual rainfall variabilities in eastern Democratic Republic of Congo (DRC). This study was conducted in the Ruzizi Plain, a dryland area, to assess the performance of maize (Zea mays L.) under two Representative Concentration Pathways (RCP 4.5 and 8.5) and two SWC practices (tied ridges and conventional tillage). The AgMIP’s Regional Integrated Assessment (RIA) approach was used to simulate Water Use Efficiency (WUE) under the Cropping System Model–Crop Environment Resource Synthesis (CSM–CERES–Maize) of the Decision Support System for Agro–technology Transfer (DSSAT). The model was calibrated using experimental data from nine cropping seasons (2011–2018) and 100 farms. The model sensitivity was assessed as a function of temperature, water, and SWC practices for the same environments. Initial conditions of crop management practices were used as input data for CSM–CERES–Maize. Current climate data were extracted from AgMERRA datasets corrected with local data for the period of 1980 to 2021. Future climate projections (2022–2099) were obtained after down−scaling the data from the 29 General Circulation Models (GCMS) of Coupled Model Intercomparison Project 5 (CMIP5) and subsetted to five GCMs based on climate regimes. GCMS results were a strong indicator that climate change in this DRC dryland will result in an increase in average annual temperatures for both RCP 4.5 and 8.5, with the highest increase (3.05 ◦C) under hot/dry conditions for RCP8.5 and the lowest (1.04 ◦C) under cool/dry conditions for RCP 4.5. All the models selected for five climate regimes for 2022–2099 showed no change in the rainfall trends for RCP 4.5 (p > 0.05). The models projected yield declines of 5–25%, with less yield losses under tied ridges as an adaptation practice. The use of efficient SWC practices could therefore be a promising strategy in reducing potential losses from climate change in drylands of eastern DRC

Current Practices and Prospects of Climate-Smart Agriculture in Democratic Republic of Congo: A Review

peer reviewedClimate-smart agriculture (CSA) is one of the innovative approaches for sustainably increasing the agricultural productivity, improving livelihoods and incomes of farmers, while at the same time improving resilience and contributing to climate change mitigation. In spite of the fact that there is neither explicit policy nor practices branded as CSA in Democratic Republic of Congo (DRC), farmers are utilizing an array of farming practices whose attributes meet the CSA criteria. However, the intensity, distribution, efficiency, and dynamics of use as well as the sources of these technologies are not sufficiently documented. Therefore, this review paper provides a comprehensive evidence of CSA-associated farming practices in DRC, public and private efforts to promote CSA practices, and the associated benefits accruing from the practices as deployed by farmers in the DRC. We find evidence of progress among farming communities in the use of practices that can be classified as CSA. Communities using these practices are building on the traditional knowledge systems and adaptation of introduced technologies to suit the local conditions. Reported returns on use of these practices are promising, pointing to their potential continued use into the future. While progressive returns on investment are reported, they are relatively lower than those reported from other areas in sub-Saharan Africa deploying similar approaches. We recommend for strategic support for capacity building at various levels, including public institutions for policy development and guidance, extension and community level to support uptake of technologies and higher education institutions for mainstreaming CSA into curricula and training a generation of CSA sensitive human resources

Trends in obesity and diabetes across Africa from 1980 to 2014: an analysis of pooled population-based studies

Background: The 2016 Dar Es Salaam Call to Action on Diabetes and Other non-communicable diseases (NCDs) advocates national multi-sectoral NCD strategies and action plans based on available data and information from countries of sub-Saharan Africa and beyond. We estimated trends from 1980 to 2014 in age-standardized mean body mass index (BMI) and diabetes prevalence in these countries, in order to assess the co-progression and assist policy formulation. Methods: We pooled data from African and worldwide population-based studies which measured height, weight and biomarkers to assess diabetes status in adults aged ≥ 18 years. A Bayesian hierarchical model was used to estimate trends by sex for 200 countries and territories including 53 countries across five African regions (central, eastern, northern, southern and western), in mean BMI and diabetes prevalence (defined as either fasting plasma glucose of ≥ 7.0 mmol/l, history of diabetes diagnosis, or use of insulin or oral glucose control agents). Results: African data came from 245 population-based surveys (1.2 million participants) for BMI and 76 surveys (182 000 participants) for diabetes prevalence estimates. Countries with the highest number of data sources for BMI were South Africa (n = 17), Nigeria (n = 15) and Egypt (n = 13); and for diabetes estimates, Tanzania (n = 8), Tunisia (n = 7), and Cameroon, Egypt and South Africa (all n = 6). The age-standardized mean BMI increased from 21.0 kg/m2 (95% credible interval: 20.3–21.7) to 23.0 kg/m2 (22.7–23.3) in men, and from 21.9 kg/m2 (21.3–22.5) to 24.9 kg/m2 (24.6–25.1) in women. The age-standardized prevalence of diabetes increased from 3.4% (1.5–6.3) to 8.5% (6.5–10.8) in men, and from 4.1% (2.0–7.5) to 8.9% (6.9–11.2) in women. Estimates in northern and southern regions were mostly higher than the global average; those in central, eastern and western regions were lower than global averages. A positive association (correlation coefficient ≃ 0.9) was observed between mean BMI and diabetes prevalence in both sexes in 1980 and 2014. Conclusions: These estimates, based on limited data sources, confirm the rapidly increasing burden of diabetes in Africa. This rise is being driven, at least in part, by increasing adiposity, with regional variations in observed trends. African countries’ efforts to prevent and control diabetes and obesity should integrate the setting up of reliable monitoring systems, consistent with the World Health Organization’s Global Monitoring System Framework

May Measurement Month 2018: a pragmatic global screening campaign to raise awareness of blood pressure by the International Society of Hypertension

Aims Raised blood pressure (BP) is the biggest contributor to mortality and disease burden worldwide and fewer than half of those with hypertension are aware of it. May Measurement Month (MMM) is a global campaign set up in 2017, to raise awareness of high BP and as a pragmatic solution to a lack of formal screening worldwide. The 2018 campaign was expanded, aiming to include more participants and countries. Methods and results Eighty-nine countries participated in MMM 2018. Volunteers (≥18 years) were recruited through opportunistic sampling at a variety of screening sites. Each participant had three BP measurements and completed a questionnaire on demographic, lifestyle, and environmental factors. Hypertension was defined as a systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg, or taking antihypertensive medication. In total, 74.9% of screenees provided three BP readings. Multiple imputation using chained equations was used to impute missing readings. 1 504 963 individuals (mean age 45.3 years; 52.4% female) were screened. After multiple imputation, 502 079 (33.4%) individuals had hypertension, of whom 59.5% were aware of their diagnosis and 55.3% were taking antihypertensive medication. Of those on medication, 60.0% were controlled and of all hypertensives, 33.2% were controlled. We detected 224 285 individuals with untreated hypertension and 111 214 individuals with inadequately treated (systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg) hypertension. Conclusion May Measurement Month expanded significantly compared with 2017, including more participants in more countries. The campaign identified over 335 000 adults with untreated or inadequately treated hypertension. In the absence of systematic screening programmes, MMM was effective at raising awareness at least among these individuals at risk