Adoption and impact of integrated Striga and soil fertility management strategy in Mali

The possibility to vary the energy matrix, thus reducing the dependency on fossil fuels, has amplified the acceptance of biomass as an alternative fuel. Despite being a cheap and renewable option of waste from agriculture and forestry activities, the use of these materials has barriers due to its low density and low energetic efficiency, which can raise the costs of its utilization. Biomass densification has drawn attention due to its advantage in comparison to in natura biomass due to its better physical and combustion characteristics. Work has been carried out in this areas namely in the densification (briquettes) forestry wastes, kiwi and vine punning waste and their respectively elementary characterization. In a subsequent step, this work also presents the study of the thermal performance and combustion hygiene of the different briquettes produced in a burning hot water boiler. The thermal efficiency was determined by the direct method and it was found that the boiler thermal performance was quite similar for the different types of fuel tested and did not depend on the fuel feeding rate

Evaluation de la protection personnelle contre les Anophelinae par utilisation de moustiquaires détériorées imprégnées de répulsifs

L’efficacité de moustiquaires détériorées imprégnées avec des répulsifs (DEET et KBR 3023) ou avec la perméthrine a été évaluée dans la protection contre Anopheles gambiae s.l. L’étude a été conduite dans le village de Goden près de Ouagadougou. Les moustiquaires ont été installées dans des cases sélectionnées dans le village et les moustiques ont été échantillonnés à l’aide de pièges lumineux CDC, de captures manuelles et de pièges à sortie. Les résultats montrent que le nombre de moustiques capturé ainsi que leur état physiologique varie selon le traitement et le degré de détérioration de la moustiquaire. La réduction de l’agressivité exprimée par les moustiques gorgés est plus importante avec le DEET et le KBR 3023 qu’avec la perméthrine (57%, 76% et 43% respectivement). Ce résultat est observé pour une surface de détérioration égale à 0,1% et une tendance similaire est observée à 1% de surface de détérioration. L’efficacité des moustiquaires varie en fonction de la case, de la surface de détérioration et du temps après imprégnation de la moustiquaire. Le KBR 3023 procure la meilleure protection par rapport aux autres traitements et même par rapport à la moustiquaire intacte lorsque la surface de détérioration est faible (0,1%). L’utilisation des répulsifs en imprégnation pourrait accroître l’efficacité des moustiquaires usagées.Mots clés: DEET, KBR 3023, Perméthrine, fraction agressive, rémanence, moustiquaires endommagées &#160

Mosquito-associated viruses and their related mosquitoes in West Africa

Mosquito-associated viruses (MAVs), including mosquito-specific viruses (MSVs) and mosquito-borne (arbo)viruses (MBVs), are an increasing public, veterinary, and global health concern, and West Africa is projected to be the next front for arboviral diseases. As in-depth knowledge of the ecologies of both western African MAVs and related mosquitoes is still limited, we review available and comprehensive data on their diversity, abundance, and distribution. Data on MAVs' occurrence and related mosquitoes were extracted from peer-reviewed publications. Data on MSVs, and mosquito and vertebrate host ranges are sparse. However, more data are available on MBVs (i.e., dengue, yellow fever, chikungunya, Zika, and Rift Valley fever viruses), detected in wild and domestic animals, and humans, with infections more concentrated in urban areas and areas affected by strong anthropogenic changes. Aedes aegypti, Culex quinquefasciatus, and Aedes albopictus are incriminated as key arbovirus vectors. These findings outline MAV, related mosquitoes, key knowledge gaps, and future research areas. Additionally, these data highlight the need to increase our understanding of MAVs and their impact on host mosquito ecology, to improve our knowledge of arbovirus transmission, and to develop specific strategies and capacities for arboviral disease surveillance, diagnostic, prevention, control, and outbreak responses in West Africa

Biological activities of four essential oils against Anopheles gambiae in Burkina Faso and their in vitro inhibition of acetylcholinesterase

The control of malaria is still a challenge partly due to mosquito’s resistance to current available insecticides. The aim of this work was to evaluate the ovicidal, larvicidal and repellent activities of Lantana camara, Hyptis suaveolens, Hyptis spicigera and Ocimum canum essential oils against  Anopheles gambiae s.l.  according to the World Health Organization standard method. The in vitro acetylcholinesterase inhibition activity of these oils was also evaluated. The repellent effect using the method of “separated arms” was evaluated. Lantana camara oil was more effective on both eggs and larvae. The LD50 and LD90 values observed in this oil solution were respectively 53.59 and 170.89 ppm on eggs whereas LD50 and LD90 were 61 and 125 ppm respectively on larvae. All oils exhibited repellent activities against adult mosquitoes. The most effective repellent was the oil of Hyptis suaveolens with a 50% efficacy dose value of 67 ppm. The highest  cetylcholinesterase inhibitory activity was observed with O. canum and H. suaveolens essential oils which IC50 was 0.21 and 0.55 μg/ml respectively. Results suggest that these essential oils have a potential for vector control and can be considered as a source of natural and ecofriendly substances for malaria vector control.Keywords: Anopheles gambiae s.l., malaria, essential oil, acetylcholinesterase, insecticidal activity

Preclinical antimalarial combination studies: the case of M5717, a P. falciparum elongation factor 2 inhibitor and pyronaridine, a hemozoin formation inhibitor

Antimalarial drug resistance in the; Plasmodium falciparum; parasite poses a constant challenge for drug development. To mitigate this risk, new antimalarial medicines should be developed as fixed-dose combinations. Assessing the pharmacodynamic interactions of potential antimalarial drug combination partners during early phases of development is essential in developing the targeted parasitological and clinical profile of the final drug product. Here, we have studied the combination of M5717, a; P. falciparum; translation elongation factor 2 inhibitor, and pyronaridine, an inhibitor of hemozoin formation. Our test cascade consisted of; in vitro; isobolograms as well as; in vivo; studies in the; P. falciparum; severe combined immunodeficient (SCID) mouse model. We also analyzed pharmacokinetic and pharmacodynamic parameters, including genomic sequencing of recrudescent parasites. We observed no pharmacokinetic interactions with the combination of M5717 and pyronaridine. M5717 did not negatively impact the rate of kill of the faster-acting pyronaridine, and the latter was able to suppress the selection of M5717-resistant mutants, as well as significantly delay the recrudescence of parasites both with suboptimal and optimal dosing regimens

A watershed approach to managing rainfed agriculture in the semiarid region of southern Mali: integrated research on water and land use

Soil and water conservation (SWC) practices like that of erosion control and soil fertility measures were commonly practiced in the semiarid region of southern Mali since the 1980s. The SWC practices were mainly meant to increase water availability in the subsurface, reduce farm water runoff and gully formation and improve nutrient content of the soil, thereby increasing crop yield. Despite such efforts to promote at scale SWC practices, the landscape of southern Mali is still affected by high rates of runoff and soil erosion and low crop yield in farmers’ fields. Data are lacking on previous beneficial SWC practices that could be adapted for wider application. In this paper, a watershed approach to managing rainfed agriculture is presented to show potential benefits of SWC practices at field and watershed scales. The approach included (1) community participation in establishing and monitoring new sets of hydro-meteorological monitoring stations and field experiments; (2) studying the dynamics and consumptive water uses of different land uses over time; and (3) evaluating the biophysical and economic advantages of SWC practices implemented in the watershed. Results showed that over a period of 34 years (1980–2014) cropping area and consumptive water uses of crops (sorghum and cotton) increased at the expenses of natural vegetation. However, the yield of these crops remained low, indicating that soil fertility management and soil moisture were insufficient. In such cases, implementation of more SWC practices can help provide the additional soil moisture required

Impact of Crop Diversification on Household Food and Nutrition Security in Southern and Central Mali

Many African countries, including Mali, depend on the production of a single or a limited range of crops for national food security. In Mali, this heavy reliance on a range of basic commodities or staple crops, or even just one, exacerbates multiple risks to agricultural production, rural livelihoods, and nutrition. With this in mind, the smart food campaign was initiated to strengthen the resilience and nutritional situation of households and peasant communities where the diet is mainly cereal-based and remains very undiversified and poor in essential micronutrients. As part of the campaign, our study aims to analyze the impact of agricultural diversification on food consumption and household nutritional security. The analysis uses survey data from 332 individuals randomly selected. Multinomial logistic regression and the Simpson diversity index were used to determine the index and estimate the determinants of crop diversification. The consumption score index weighted by consumption frequency and anthropometric indices (for children) were used to assess the nutritional status of households. The results show four types of strategies of diversification: 7.55% are cereals only, 5.66% combine millet–sorghum–groundnut, 41.51% combine millet–sorghum–groundnut–cowpea, and 45.28% combine millet–sorghum–groundnut–cowpea–maize. The estimation of the regression model shows that socioeconomic factors have a positive influence. With a consumption score index of 34 in the villages and 40.5 in Bamako, based on eight food groups, we find that the quality of food is insufficient in rural areas, but it is acceptable in the urban center of Bamako. Analysis of the nutritional status of children aged 6–48 months reveals that 30% of the surveyed population is in a situation of nutritional insecurity (all forms combined). To help improve crop diversification and the nutritional quality of foods, we suggest, among other things, subsidies and public spending tofacilitate access to inputs that allow the acquisition of a wider range of inputs and services, intensification of nutrition awareness, and education programs to maximize the incentive to consume nutritious foods from self-production and market purchases. Finally, we propose to facilitate access to technologies promoting food diversification and improving food and nutritional security, particularly in rural areas

Perceptions on Sack Gardening in Rural Areas: The Case of Vegetable Stakeholders in Koutiala and Bougouni, Mali

Abstract: Understanding the perception of sack gardening technology is important in order to better support the adoption of sack gardening in households, given the nutritional role vegetables play. This notwithstanding, research has not yet been carried out to understand the stakeholders’ perception of sack gardening technology in the zones of Bougouni and Koutiala, where sack gardening technology was introduced under the Africa Research in Sustainable Intensification for the Next Generation (Africa-RISING) project. This study assessed the perception of farm households on sack gardening technology and specifically to understand to what extent this innovation responds to household needs. Q-methodology was used to identify rural household’s viewpoints and principal component analysis (PCA) was performed to compare stakeholders’ opinion typologies to discourses retained by Q-method results. Focus group discussions were used to identify the statements used for the q-set in the individual surveys. Our findings showed three factors or discourses which reflected the stakeholders’ viewpoints. A nutritional role, the role of making vegetables available for household consumption and the role of environment protection, specifically soil protection, were indicated in the stakeholders’ opinions. The understanding of the different discourses retained provides insights that can be used to design public and private interventions to support the usage of the technology in households or the adoption of this technology

Phenotypic Insecticide Resistance in Anopheles gambiae (Diptera: Culicidae): Specific Characterization of Underlying Resistance Mechanisms Still Matters

An effective control of malaria vectors requires an extensive knowledge of mechanisms underlying the resistance-phenotypes developed by these vectors against insecticides. We investigated Anopheles gambiae mosquitoes from Benin and Togo for their intensity of insecticide resistance and we discussed the involvement of genotyped mechanisms in the resistance-phenotypes observed. Three- to five-day-old adult mosquitoes emerged from field and laboratory An. gambiae larvae were assayed using WHO tube intensity tests against various doses of deltamethrin: 1× (0.05%); 2× (0.1%); 5× (0.25%); 7.5× (0.375%) and those of pirimiphos-methyl: 0.5× (0.125%); 1× (0.25%). Members of An. gambiae complex were screened in field populations using polymerase chain reaction (PCR) assays. The presence of kdrR(1014F/1014S) and ace-1R(119S) mutations was also investigated using TaqMan and PCR-RFLP techniques, respectively. Anopheles gambiae from field were very resistant to deltamethrin, whereas KisKdr and AcerKdrKis strains displayed 100% mortality rates at 2× the diagnostic dose. In contrast, the field mosquitoes displayed a low resistance-intensity against 1× the diagnostic dose of pirimiphos-methyl, whereas AcerKis and AcerKdrKis strains showed susceptibility at 0.5× the diagnostic dose. Anopheles gambiae s.s., Anopheles coluzzii, and Anopheles arabiensis were identified. Allelic frequencies of kdrR (1014F) and ace-1R (119S) mutations in the field populations varied from 0.65 to 1 and 0 to 0.84, respectively. The field An. gambiae displayed high-resistance levels against deltamethrin and pirimiphos-methyl when compared with those of the laboratory An. gambiae-resistant strains. These results exhibit the complexity of underlying insecticide resistance mechanisms in these field malaria vectors