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Background: Desmodium species used as intercrops in push-pull cropping systems are known to repel insect-pests, suppress Striga species weeds, and shift soil microbiome. However, the mechanisms through which Desmodium species impact the soil microbiome, either through its root exudates, changes in soil nutrition, or shading microbes from its nodules into the rhizosphere, are less understood. Here, we investigated the diversity of root-nodule microbial communities of three Desmodium species- Desmodium uncinatum (SLD), Desmodium intortum (GLD), and Desmodium incanum (AID) which are currently used in smallholder maize push-pull technology (PPT). Methods: Desmodium species root-nodule samples were collected from selected smallholder farms in western Kenya, and genomic DNA was extracted from the root-nodules. The amplicons underwent paired-end Illumina sequencing to assess bacterial and fungal populations. Results: We found no significant differences in composition and relative abundance of bacterial and fungal species within the root-nodules of the three Desmodium species. While a more pronounced shift was observed for fungal community compositions compared to bacteria, no significant differences were observed in the general diversity (evenness and richness) of fungal and bacterial populations among the three Desmodium species. Similarly, beta diversity was not significantly different among the three Desmodium species. The root-nodule microbiome of the three Desmodium species was dominated by Bradyrhizobium and Fusarium species. Nevertheless, there were significant differences in the proportion of marker gene sequences responsible for energy and amino acid biosynthesis among the three Desmodium species, with higher sequence proportions observed in SLD. Conclusion: There is no significant difference in the microbial community of the three Desmodium species used in PPT. However, root-nodule microbiome of SLD had significantly higher marker gene sequences responsible for energy and amino acid biosynthesis. Therefore, it is likely that the root-nodules of the three Desmodium species host similar microbiomes and influence soil health, consequently impacting plant growth and agroecosystem functioning.
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Intensification of staple crops through conventional agricultural practices with chemical synthetic inputs has yielded positive outcomes in food security but with negative environmental impacts. Ecological intensification using cropping systems such as maize edible-legume intercropping (MLI) systems has the potential to enhance soil health, agrobiodiversity and significantly influence crop productivity. However, mechanisms underlying enhancement of biological soil health have not been well studied. This study investigated the shifts in rhizospheric soil and maize-root microbiomes and associated soil physico-chemical parameters in MLI systems of smallholder farms in comparison to maize-monoculture cropping systems (MMC). Maize-root and rhizospheric soil samples were collected from twenty-five farms each conditioned by MLI and MMC systems in eastern Kenya. Soil characteristics were assessed using Black oxidation and Walkley methods. High-throughput amplicon sequencing was employed to analyze fungal and bacterial communities, predicting their functional roles and diversity. The different MLI systems significantly impacted soil and maize-root microbial communities, resulting in distinct microbe sets. Specific fungal and bacterial genera and species were mainly influenced and enriched in the MLI systems (e.g., Bionectria solani, Sarocladium zeae, Fusarium algeriense, and Acremonium persicinum for fungi, and Bradyrhizobium elkanii, Enterobacter roggenkampii, Pantoea dispersa and Mitsuaria chitosanitabida for bacteria), which contribute to nutrient solubilization, decomposition, carbon utilization, plant protection, bio-insecticides/fertilizer production, and nitrogen fixation. Conversely, the MMC systems enriched phytopathogenic microbial species like Sphingomonas leidyi and Alternaria argroxiphii. Each MLI system exhibited a unique composition of fungal and bacterial communities that shape belowground biodiversity, notably affecting soil attributes, plant well-being, disease control, and agroecological services. Indeed, soil physico-chemical properties, including pH, nitrogen, organic carbon, phosphorus, and potassium were enriched in MLI compared to MMC cropping systems. Thus, diversification of agroecosystems with MLI systems enhances soil properties and shifts rhizosphere and maize-root microbiome in favor of ecologically important microbial communities.
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Microbiología del Suelo , Suelo , Zea mays , Zea mays/crecimiento & desarrollo , Zea mays/microbiología , Suelo/química , Agricultura/métodos , Rizosfera , Microbiota , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/microbiología , Ecosistema , Raíces de Plantas/microbiología , Raíces de Plantas/crecimiento & desarrollo , Biodiversidad , Bacterias/clasificación , Bacterias/genética , Bacterias/crecimiento & desarrollo , Hongos/genética , Hongos/clasificación , Kenia , Producción de Cultivos/métodosRESUMEN
Concerned with sustainably alleviating mental distress and promoting the right to health worldwide, global mental health (GMH) is practised across various contexts spanning the humanitarian-development-peace nexus. The inherently intersectoral and multidisciplinary nature of GMH calls for competency frameworks and training programmes that embody diversity, decolonisation and multiprofessionalism. Existing competency frameworks have failed to capture the multi-sectoral, inter-professional nature of contemporary GMH practice. In response to these needs, a qualitative content analysis of relevant job advertisements was conducted to distil a comprehensive set of professional competencies in contemporary GMH practice. Approximately 200 distinct skills and competencies were extracted from 70 job advertisements and organised into four meta-dimensions: 'skills', 'sector', 'self' and 'subject'. The first known systematic attempt at a multi-sectoral GMH competency framework, it offers a springboard for exploring vital yet overlooked professional competencies such as resilience, self-reflection, political skills and entrepreneurialism. On this basis, recommendations for building a competent, agile and effective GMH workforce with diversified and future-proof skillsets are proposed. The framework can also inform inter-professional training and curriculum design, and capacity-building initiatives aimed at early-career professional development, particularly in low- and middle-income settings.
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BACKGROUND: The soil biota consists of a complex assembly of microbial communities and other organisms that vary significantly across farming systems, impacting soil health and plant productivity. Despite its importance, there has been limited exploration of how different cropping systems influence soil and plant root microbiomes. In this study, we investigated soil physicochemical properties, along with soil and maize-root microbiomes, in an agroecological cereal-legume companion cropping system known as push-pull technology (PPT). This system has been used in agriculture for over two decades for insect-pest management, soil health improvement, and weed control in sub-Saharan Africa. We compared the results with those obtained from maize-monoculture (Mono) cropping system. RESULTS: The PPT cropping system changed the composition and diversity of soil and maize-root microbial communities, and led to notable improvements in soil physicochemical characteristics compared to that of the Mono cropping system. Distinct bacterial and fungal genera played a crucial role in influencing the variation in microbial diversity within these cropping systems. The relative abundance of fungal genera Trichoderma, Mortierella, and Bionectria and bacterial genera Streptomyces, RB41, and Nitrospira were more enriched in PPT. These microbial communities are associated with essential ecosystem services such as plant protection, decomposition, carbon utilization, bioinsecticides production, nitrogen fixation, nematode suppression, phytohormone production, and bioremediation. Conversely, pathogenic associated bacterial genus including Bryobacter were more enriched in Mono-root. Additionally, the Mono system exhibited a high relative abundance of fungal genera such as Gibberella, Neocosmospora, and Aspergillus, which are linked to plant diseases and food contamination. Significant differences were observed in the relative abundance of the inferred metabiome functional protein pathways including syringate degradation, L-methionine biosynthesis I, and inosine 5'-phosphate degradation. CONCLUSION: Push-pull cropping system positively influences soil and maize-root microbiomes and enhances soil physicochemical properties. This highlights its potential for agricultural and environmental sustainability. These findings contribute to our understanding of the diverse ecosystem services offered by this cropping system where it is practiced regarding the system's resilience and functional redundancy. Future research should focus on whether PPT affects the soil and maize-root microbial communities through the release of plant metabolites from the intercrop root exudates or through the alteration of the soil's nutritional status, which affects microbial enzymatic activities.
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Microbiota , Resiliencia Psicológica , Suelo/química , Zea mays , Hongos/genética , Agricultura/métodos , Bacterias/genética , Microbiología del SueloRESUMEN
OBJECTIVE: To investigate the prevalence of cardiometabolic risk factors (CMRFs), target organ damage (TOD) and its associated factors among adults in Freetown, Sierra Leone. DESIGN: This community-based cross-sectional study used a stratified multistage random sampling method to recruit adult participants. SETTING: The health screening study was conducted between October 2019 and October 2021 in Western Area Urban, Sierra Leone. PARTICIPANTS: A total of 2394 adult Sierra Leoneans aged 20 years or older were enrolled. OUTCOME MEASURE: Anthropometric data, fasting lipid profiles, fasting plasma glucose, TOD, clinical profiles and demographic characteristics of participants were described. The cardiometabolic risks were further related to TOD. RESULTS: The prevalence of known CMRFs was 35.3% for hypertension, 8.3% for diabetes mellitus, 21.1% for dyslipidaemia, 10.0% for obesity, 13.4% for smoking and 37.9% for alcohol. Additionally, 16.1% had left ventricular hypertrophy (LVH) by ECG, 14.2% had LVH by two-dimensional echo and 11.4% had chronic kidney disease (CKD). The odds of developing ECG-LVH were higher with diabetes (OR=1.255, 95% CI (0.822 to 1.916) and dyslipidaemia (OR=1.449, 95% CI (0.834 to 2.518). Associated factors for higher odds of Left Ventricular Mass Index by echo were dyslipidaemia (OR=1.844, 95% CI (1.006 to 3.380)) and diabetes mellitus (OR=1.176, 95% CI (0.759 to 1.823)). The odds of having CKD were associated with diabetes mellitus (OR=1.212, 95% CI (0.741 to 1.983)) and hypertension (OR=1.163, 95% CI (0.887 to 1.525)). A low optimal cut-off point for ECG-LVH (male 24.5 mm vs female 27.5 mm) was required to maximise sensitivity and specificity by a receiver operating characteristics curve since the odds for LVH by ECG were low. CONCLUSIONS: This study provides novel data-driven information on the burden of CMRF and its association with preclinical TOD in a resource-limited setting. It illustrates the need for interventions in improving cardiometabolic health screening and management in Sierra Leonean.
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Diabetes Mellitus , Hipertensión , Insuficiencia Renal Crónica , Adulto , Humanos , Masculino , Femenino , Sierra Leona/epidemiología , Factores de Riesgo , Estudios Transversales , Factores de Riesgo Cardiometabólico , Hipertensión/complicaciones , Diabetes Mellitus/epidemiología , Hipertrofia Ventricular Izquierda , Insuficiencia Renal Crónica/complicaciones , PrevalenciaRESUMEN
Following its recent invasion of African countries, fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), now co-exists with resident stemborers such as Busseola fusca (Lepidoptera: Noctuidae) and Chilo partellus (Lepidoptera: Crambidae) causing severe damage to maize crops. Due to niche overlap, interspecific interactions occur among the three species, but the mechanisms and degree remain unclear. In this study, we assessed plant-mediated intraspecific and interspecific interactions, predation in laboratory and semi-field settings, and larval field occurrence of S. frugiperda and the two stemborer species. Larval feeding assays to evaluate competitive plant-mediated interactions demonstrated that initial S. frugiperda feeding negatively affected subsequent stemborer larval feeding and survival, suggesting induction of herbivore-induced mechanisms by S. frugiperda, which deters establishment and survival of competing species. Predation assays showed that, at different developmental larval stages, second−sixth instars of S. frugiperda preyed on larvae of both B. fusca and C. partellus. Predation rates of S. frugiperda on stemborers was significantly higher than cannibalism of S. frugiperda and its conspecifics (p < 0.001). Cannibalism of S. frugiperda in the presence of stemborers was significantly lower than in the presence of conspecifics (p = 0.04). Field surveys showed a significantly higher number of S. frugiperda larvae than stemborers across three altitudinally different agroecological zones (p < 0.001). In conclusion, this study showed that the invasive S. frugiperda exhibited a clear competitive advantage over resident stemborers within maize cropping systems in Kenya. Our findings reveal some of the possible mechanisms employed by S. frugiperda to outcompete resident stemborers and provide crucial information for developing pest management strategies for these lepidopteran pests.
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Background: Psychiatric bed numbers (general, forensic, and residential) and prison populations have been considered indicators of institutionalization. The present study aimed to assess changes of those indicators across sub-Saharan Africa (SSA) from 1990 to 2020. Methods: We retrospectively obtained data on psychiatric bed numbers and prison populations from 46 countries in SSA between 1990 and 2020. Mean and median rates, as well as percentage changes between first and last data points were calculated for all of SSA and for groups of countries based on income levels. Results: Primary data were retrieved from 17 out of 48 countries. Data from secondary sources were used for 29 countries. From two countries, data were unavailable. The median rate of psychiatric beds decreased from 3.0 to 2.2 per 100 000 population (median percentage change = -16.1%) between 1990 and 2020. Beds in forensic and residential facilities were nonexistent in most countries of SSA in 2020, and no trend for building those capacities was detected. The median prison population rate also decreased from 77.8 to 71.0 per 100 000 population (-7.8%). There were lower rates of psychiatric beds and prison populations in low-income and lower-middle income countries compared with upper-middle income countries. Conclusions: SSA countries showed, on average, a reduction of psychiatric bed rates from already very low levels, which may correspond to a crisis in acute psychiatric care. Psychiatric bed rates were, on average, about one twenty-fifth of countries in the Organization for Economic Co-operation and Development (OECD), while prison population rates were similar. The heterogeneity of trends among SSA countries over the last three decades indicates that developments in the region may not have been based on coordinated policies and reflects unique circumstances faced by the individual countries.
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Prisiones , África del Sur del Sahara/epidemiología , Humanos , Estudios RetrospectivosRESUMEN
Grain legumes play a significant role in smallholder farming systems in Africa because of their contribution to nutrition and income security and their role in fixing nitrogen. Biological Nitrogen Fixation (BNF) serves a critical role in improving soil fertility for legumes. Although much research has been conducted on rhizobia in nitrogen fixation and their contribution to soil fertility, much less is known about the distribution and diversity of the bacteria strains in different areas of the world and which of the strains achieve optimal benefits for the host plants under specific soil and environmental conditions. This paper reviews the distribution, characterization, and commercialization of elite rhizobia strains in Africa.
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Fabaceae , Rhizobium , Fabaceae/microbiología , Fijación del Nitrógeno , Suelo , SimbiosisRESUMEN
Sierra Leone is a West African country with a population of just over 7 million. Many Sierra Leoneans lived through the psychologically distressing events of the civil war (1991-2002), the 2014 Ebola outbreak and frequent floods. Traditionally, mental health services have been delivered at the oldest mental health hospital in sub-Saharan Africa, with no services available anywhere else in the country. Mental illness remains highly stigmatised. Recent advances include revision of the Mental Health Policy and Strategic Plan and the strengthening of mental health governance and district services. Many challenges lie ahead, with the crucial next steps including securing a national budget line for mental health, reviewing mental health legislation, systematising training of mental health specialists and prioritising the procurement of psychotropic medications. National and international commitment must be made to reduce the treatment gap and provide quality care for people with mental illness in Sierra Leone.
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INTRODUCTION: Trauma accounts for a significant proportion of the global burden of disease, with highest mortality rates seen in Africa. This epidemic is predicted to increase with urbanisation and an aim of the Sustainable Development Goals is to reduce deaths and trauma caused by road accidents. Data available on urban trauma in Sierra Leone is limited. METHODS: We conducted a retrospective observational study of trauma and injury related presentations to the emergency centre (EC) of Connaught Hospital, the principal adult tertiary referral centre in Freetown, Sierra Leone between January and March 2016. Patient demographics are described with mechanism of injury. Additional data on length of stay and surgical procedures were recorded for admissions to the trauma ward. RESULTS: During the 3-month period, a total of 340 patients with injury presented to the EC, accounting for 11.6% of total attendances and 68% of adult surgical admissions. The majority were male (66%) and mean age was 26â¯years (IQR 15-40). The proportion of trauma presentations were higher in the evening and at weekends and 41% of patients were triaged as emergency or very urgent cases. Road traffic accidents were the most frequent cause of injury (55%) followed by falls (17%) and assaults (14%). Burns were more common in children. Head and lower limbs were the most commonly injured body parts and a minority of patients underwent surgical procedures. Median length of stay for adult patients was 4.5â¯days (IQR 2-11) and 7â¯days (IQR 4-14) for children. DISCUSSION: Injury accounts for a high burden of disease at Connaught Hospital and consumes a significant proportion of EC and hospital resources. Efforts should be directed towards strengthening the pre-hospital and emergency trauma systems with accurate, formal data collection as well as targeting injury prevention initiatives and improving road safety to reduce morbidity and mortality.
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The West African Ebola epidemic of 2013-2016 was by far the largest outbreak of the disease on record. Sierra Leone suffered nearly half of the 28,646 reported cases. This paper presents a set of culturally contextualized Ebola messages that are based on the findings of qualitative interviews and focus group discussions conducted in 'hotspot' areas of rural Bombali District and urban Freetown in Sierra Leone, between January and March 2015. An iterative approach was taken in the message development process, whereby (i) data from formative research was subjected to thematic analysis to identify areas of community concern about Ebola and the national response; (ii) draft messages to address these concerns were produced; (iii) the messages were field tested; (iv) the messages were refined; and (v) a final set of messages on 14 topics was disseminated to relevant national and international stakeholders. Each message included details of its rationale, audience, dissemination channels, messengers, and associated operational issues that need to be taken into account. While developing the 14 messages, a set of recommendations emerged that could be adopted in future public health emergencies. These included the importance of embedding systematic, iterative qualitative research fully into the message development process; communication of the subsequent messages through a two-way dialogue with communities, using trusted messengers, and not only through a one-way, top-down communication process; provision of good, parallel operational services; and engagement with senior policy makers and managers as well as people in key operational positions to ensure national ownership of the messages, and to maximize the chance of their being utilised. The methodological approach that we used to develop our messages along with our suggested recommendations constitute a set of tools that could be incorporated into international and national public health emergency preparedness and response plans.
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Control de Enfermedades Transmisibles/métodos , Educación en Salud/métodos , Conocimientos, Actitudes y Práctica en Salud , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Fiebre Hemorrágica Ebola/psicología , Humanos , Entrevistas como Asunto , Sierra Leona/epidemiologíaRESUMEN
BACKGROUND: Kenema Government Hospital (KGH) has developed an advanced clinical and laboratory research capacity to manage the threat of Lassa fever, a viral hemorrhagic fever (VHF). The 2013-2016 Ebola virus (EBOV) disease (EVD) outbreak is the first to have occurred in an area close to a facility with established clinical and laboratory capacity for study of VHFs. METHODS: Because of its proximity to the epicenter of the EVD outbreak, which began in Guinea in March 2014, the KGH Lassa fever Team mobilized to establish EBOV surveillance and diagnostic capabilities. RESULTS: Augustine Goba, director of the KGH Lassa laboratory, diagnosed the first documented case of EVD in Sierra Leone, on 25 May 2014. Thereafter, KGH received and cared for numbers of patients with EVD that quickly overwhelmed the capacity for safe management. Numerous healthcare workers contracted and lost their lives to EVD. The vast majority of subsequent EVD cases in West Africa can be traced back to a single transmission chain that includes this first diagnosed case. CONCLUSIONS: Responding to the challenges of confronting 2 hemorrhagic fever viruses will require continued investments in the development of countermeasures (vaccines, therapeutic agents, and diagnostic assays), infrastructure, and human resources.
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Brotes de Enfermedades , Ebolavirus/aislamiento & purificación , Genoma Viral/genética , Fiebre Hemorrágica Ebola/epidemiología , Fiebre de Lassa/epidemiología , Virus Lassa/aislamiento & purificación , Adolescente , Adulto , África Occidental/epidemiología , Niño , Preescolar , Ebolavirus/genética , Monitoreo Epidemiológico , Femenino , Genómica , Guinea/epidemiología , Fiebre Hemorrágica Ebola/diagnóstico , Fiebre Hemorrágica Ebola/transmisión , Fiebre Hemorrágica Ebola/virología , Humanos , Fiebre de Lassa/diagnóstico , Fiebre de Lassa/transmisión , Fiebre de Lassa/virología , Virus Lassa/genética , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Sierra Leona/epidemiología , Adulto JovenRESUMEN
The 2013-2015 Ebola virus disease (EVD) epidemic is caused by the Makona variant of Ebola virus (EBOV). Early in the epidemic, genome sequencing provided insights into virus evolution and transmission and offered important information for outbreak response. Here, we analyze sequences from 232 patients sampled over 7 months in Sierra Leone, along with 86 previously released genomes from earlier in the epidemic. We confirm sustained human-to-human transmission within Sierra Leone and find no evidence for import or export of EBOV across national borders after its initial introduction. Using high-depth replicate sequencing, we observe both host-to-host transmission and recurrent emergence of intrahost genetic variants. We trace the increasing impact of purifying selection in suppressing the accumulation of nonsynonymous mutations over time. Finally, we note changes in the mucin-like domain of EBOV glycoprotein that merit further investigation. These findings clarify the movement of EBOV within the region and describe viral evolution during prolonged human-to-human transmission.
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Ebolavirus/genética , Ebolavirus/aislamiento & purificación , Genoma Viral , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/virología , Mutación , Evolución Biológica , Brotes de Enfermedades , Ebolavirus/clasificación , Fiebre Hemorrágica Ebola/transmisión , Humanos , Sierra Leona/epidemiología , Manejo de EspecímenesRESUMEN
In its largest outbreak, Ebola virus disease is spreading through Guinea, Liberia, Sierra Leone, and Nigeria. We sequenced 99 Ebola virus genomes from 78 patients in Sierra Leone to ~2000× coverage. We observed a rapid accumulation of interhost and intrahost genetic variation, allowing us to characterize patterns of viral transmission over the initial weeks of the epidemic. This West African variant likely diverged from central African lineages around 2004, crossed from Guinea to Sierra Leone in May 2014, and has exhibited sustained human-to-human transmission subsequently, with no evidence of additional zoonotic sources. Because many of the mutations alter protein sequences and other biologically meaningful targets, they should be monitored for impact on diagnostics, vaccines, and therapies critical to outbreak response.