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We use a multilevel approach to investigate whether a general and robust relationship between weather shocks and (internal and international) migration intentions can be uncovered in Western African countries. We combine individual survey data with measures of localized weather shocks for 13 countries over the 2008–2016 period. A meta-analysis on results from about 51,000 regressions is conducted to identify the specification of weather anomalies that maximizes the goodness of fit of our empirical model. We then use this best specification to document heterogeneous mobility responses to weather shocks. We find that variability in Standardized Precipitation Evapotranspiration Index/rainfall is associated with changing intentions to move locally or internationally in a few countries only. However, the significance, sign and magnitude of the effect are far from being robust and consistent across countries. These differences might be due to imperfections in the data or to differences in long-term climate conditions and adaptation capabilities. They may also suggest that credit constraints are internalized differently in different settings, or that moving internally is not a relevant option as weather conditions are spatially correlated while moving abroad is an option of last resort. Although our multilevel approach allows us to connect migration intentions with the timing and spatial dimension of weather shocks, identifying a common specification that governs weather-driven mobility decisions is a very difficult, if not impossible, task, even for countries belonging to the same region. Our findings also call for extreme caution before generalizing results from specific case studies.

Des traitements aériens à l’ActellicR M20 (Pirimiphos methyl) en formulation microencapsulée ont été réalisés sur différentes rivières du Mali et de Côte d’Ivoire, en vue de ta destruction des larves de Simulium damnosum s.l., vecteur de l’Onchocercose.A la concentration de 0,2 mg/l/10 mn, aucune mortalité de poissons n’a été observée. Par contre, les évaluations de l’intensité de dérive témoignent d’une forte toxicité des traitements vis-à-vis des invertébrés benthiques. Cet effet est maximum environ deux heures après les épandages et atteint un niveau vingt fois supérieur à celui provoqué par l’utilisation du téméphos (AbaleR) dans les conditions normales de campagne.Baetidae, Tricorythidae et Chironomidae sont parmi les taxons les plus sensibles et un niveau global de décrochement pour l’ensemble des invertébrés de l’ordre de 60 % a été obtenu sur une période de 24 heures en utilisant la méthode des « gouttières in situ ».Un tel niveau d’impact sur la faune des invertébrés n’est pas sans risque pour l’environnement aquatique et l’utilisation de l’ActellicR M20 microencapsulé sur une grande échelle n’est pas recommandable, sous la forme de ta formulation testée. Aerial applications of ActellicR M20 (Pirimiphos methyl), in a micro-encapsulated formulation were tried as a larvicide against Simulium damnosum s.l. in different rivers in Mali and Ivory Coast. Al 0.2 mg/l/10 mn concentration, no fish mortality was observed. However, drift rate measurements indicate a strong effect on the invertebrate fauna, about two hours after application with a maximum level of 20 times in comparison to a normal temephos (AbaleR) treatment.Baetidae, Tricorythidae and Chironomidae are the most sensitive taxa and a total detachment of 60% have been recorded during a 24 hours period, using the in situ gutter technique.Such an impact on the invertebrale fauna is not without any risk for the aquatic environment and the use of Actellic R M20 micro-encapsuled on a large scale is not recommended, as far as the tested formulation is concerned.

Resumo: Paulo Fernando de Moraes Farias é historiador brasileiro com renomado trabalho desenvolvido no Centre of West African Studies, da Universidade de Birmingham. Sua longa trajetória de residência e pesquisa no Reino Unido se deu após anos decisivos, em que viveu em diferentes países da África Ocidental. Perseguido politicamente pela ditadura civil-militar brasileira instaurada em 1964, Farias deixou o Centro de Estudos Afro-orientais (Ceao) da Universidade Federal da Bahia (UFBA) e vinculou-se sucessivamente a diferentes instituições acadêmicas em Gana, no Senegal e na Nigéria para desenvolver pesquisa no emergente campo da história africana. Neste texto, amparado em três entrevistas concedidas por Farias e em diversas correspondências depositadas em acervos do Ceao e da Fundação Pierre Verger (FPV), discutimos os dilemas, as descobertas e os diálogos do jovem historiador em seu exílio africano entre 1964 e 1969. Abstract: Paulo Fernando de Moraes Farias is a renowned Brazilian historian with work developed at the Centre of West African Studies at Birminghan University. His long career of residence and research in the United Kingdom came after a decisive decade in which he lived in different countries of West Africa. Persecuted politically by the Brazilian military regime established in 1964, Farias left the Center for Afro-Oriental Studies at the Federal University of Bahia and was successively linked to different academic institutions in Ghana, Senegal and Nigeria to develop research in the emerging field of African history. In this text, based on three interviews given by Farias and in several correspondence deposited in collections of the Center for Afro-Oriental Studies and Pierre Verger Foundation, we discussed the dilemmas, difficulties and dialogues of the young historian in his African exile between 1964 and 1969.

Many societal and environmental changes occurred between the 2nd millennium BC and the middle of the 2nd millennium AD in western Africa. Key amongst these were changes in land use due to the spread and development of agricultural strategies, which may have had widespread consequences for the climate, hydrology, biodiversity, and ecosystem services of the region. Quantification of these land-use influences and potential feedbacks between human and natural systems is controversial, however, in part because the archaeological and historical record is highly fragmented in time and space. To improve our understanding of how humans contributed to the development of African landscapes, we developed an atlas of land-use practices in western Africa for nine time-windows over the period 1800 BC–AD 1500. The maps are based on a broad synthesis of archaeological, archaeobotanical, archaeozoological, historical, linguistic, genetic, and ethnographic data, and present land use in 12 basic categories. The main differences between categories is the relative reliance on, and variety of, domesticated plant and animal species utilized, and the energy invested in cultivating or keeping them. The maps highlight the irregular and frequently non-linear trajectory of land-use change in the prehistory of western Africa. Representing an original attempt to produce rigorous spatial synthesis from diverse sources, the atlas will be useful for a range of studies of human–environment interactions in the past, and highlight major spatial and temporal gaps in data that may guide future field studies., Open access funding provided by Max Planck Society. This work was supported by Grants to JOK from the European Research Council (COEVOLVE, 313797), the Swiss National Science Foundation (ACACIA, CR10I2_146314), and the Fondation Herbette (2016-2-E-16). JMR was funded by the Funds for Research Training in Industry and Agriculture (National Funds for Scientific Research, Belgium) and the Leopold II Funds (Belgium). Data were also acquired in the framework of the Era-Net BiodivERsA CoForChange project, funded by the French National Research Agency and National Environment Research Council (UK).

L’enquête que Jean Rouch mène sur les migrations en pays côtiers entre 1953 et 1958 constitue un moment charnière de son parcours et pose véritablement les fondements de son œuvre, tant ethnographique que cinématographique. C’est alors qu’il contribue à renouveler les méthodes d’étude et de diffusion des résultats de ses recherches.À partir du milieu des années 1950, Jean Rouch pratique ainsi et revendique une démarche d’ethnographe-cinéaste se faisant le médiateur des phénomènes d’acculturation dans les régions qu’il étudie. Le film devient un médium permettant une mise en ordre de la connaissance ethnographique, entremêlant des questionnements sur la situation ethnographique en soi et sur la posture du cinéaste. Jean Rouch’s 1953-1958 survey of migrations to Africa’s coastal countries was a turning point in his career, and really laid the foundations of his work in both ethnography and film. It contributed to a profound revival of his study methods and the way in which he shared his research findings. From the mid-1950s, Rouch asserted his approach as an ethnographer-filmmaker, becoming a mediator of the phenomena of acculturation in the regions which he studied. Movies thus became a medium which allowed ethnographical knowledge to be ordered and arranged. It thus mixed questions about the ethnographical situation in itself with questions about the filmmaker’s position.

Herein, we describe the tadpoles of six Astylosternus species, A.fallax, A.cf.fallax, A.laurenti, A.montanus, A.perreti, A.ranoides, and Scotoblepsgabonicus, and redescribe the tadpoles of A.batesi, A.diadematus, A.laticephalus, A.occidentalis, A.rheophilus, and Nyctibatescorrugatus. All Astylosternus tadpoles are adapted to torrent currents and share a long, oval body, slightly flattened in lateral view, with very long muscular tails with narrow fins. The jaws are massive, serrated, and often show a tooth-like medial projection (fang) in the upper jaw. Body proportions of Astylosternus tadpoles are extremely similar. The best characters to distinguish species might be life coloration and potentially the shape of labial papillae. The tadpole of Scotoblepsgabonicus is similar to Astylosternus and differs only slightly by a narrower body with a shorter and rounder head. The upper jaw of Scotobleps carries two or three lateral fangs instead of one medial one. The tadpole of Nyctibatescorrugatus is easily distinguishable from the other two genera on the basis of their very long, eel-shaped body and tail and the bluish-black color.

L’objectif de cet article est de présenter les résultats préliminaires de l'étude d'une séquence sédimentaire de l'Holocène récent située dans la vallée de la Falémé au Sénégal oriental. Ce secteur fait l'objet de campagnes de fouilles archéologiques et de prospections géomorphologiques depuis 2011. Les travaux toujours en cours ont jusque-là permis de comprendre l’organisation des formes et de l’architecture des formations quaternaires de cette vallée ainsi que de fonder un cadre chronostratigraphique solide. La présence de données archéologiques abondantes a permis de replacer cette séquence dans une perspective géoarchéologique. Néanmoins, les archives sédimentaires conservées dans le fond de la vallée de la Falémé et analysées jusqu’à présent couvrent principalement la fin du Pléistocène. Initiée en 2016, l’étude d'un affluent temporaire de la Falémé, le ravin de Sansandé, a permis de déceler des archives sédimentaires de l'Holocène récent. La méthodologie consiste en l’identification puis l'analyse des formes et formations géomorphologiques. Les sondages et les études de laboratoire réalisés sur les sédiments de deux terrasses alluviales datées des deux derniers millénaires par la méthode du radiocarbone et de l’OSL mettent en évidence des rythmes de la morphogenèse principalement guidés par les changements climatiques. Ainsi, les populations ayant occupé notre zone d'étude au premier et second millénaire ont connu une variabilité de leur environnement qui a sans doute affecté leurs pratiques. Inversement, la formation de ces accumulations sédimentaires semble avoir été contrôlée par l'intensification des pratiques pastorales et agricoles dans la vallée. Ces enregistrements sédimentaires fournissent un nouveau jalon de l'évolution des interactions Environnement/Sociétés au cours de l'Holocène récent dans un espace qui comporte encore peu d’études comparables. The aim of this paper is to present the preliminary results of the study of a Recent Holocene sedimentary sequence located in the Falémé valley in Eastern Senegal (West Africa). Geomorphological prospections and archeological excavations are performed in this area since 2011. So far the research allowed an understanding of the valley geometry and the establishment of a robust chronostratigraphical framework based on OSL and radiocarbon dating. The richness of the archeological data allows the development of a geoarcheological approach. However, the sedimentary archive of the valley constrains our research on the Pleistocene period. Since 2016, the study of a temporary affluent of the Faleme River made it possible to analyze well-preserved Recent Holocene sediments. The methodology includes field work to recognize the geomorphological forms and formations observed in the ravine during the dry season. The field and laboratory work led on the sediment of two alluvial terraces allocated to the two last ka, allow us to understand the palaeoenvironmental evolution that affect this area. They highlight morphogenesis rhythms mainly driven by climate change. Thus the population who occupied the area study during that period have been exposed to a significant environmental variability, which likely affected their practice. In turn, the sedimentary accumulation seems to have been partly controlled by the intensification of pastoral and agricultural activity in the valley. These sedimentary records provide a new milestone in the evolution of Environment/Society interactions during the Late Holocene in an area that still has few comparable studies.

Background For exploring maternal death, supply and demand-side factors can be characterized by the three delays model developed by Thaddeus and Maine (1994). The model comprises delay in deciding to seek care (delay 1), delay in reaching the health facility (delay 2), and delay in receiving quality care once at the health facility (delay 3). Few studies have comprehensively dealt with the health systems delays that prevent the receipt of timely and appropriate obstetric care once a woman reaches a health facility (phase III delays). The objective of the present study was to identify facility-level barriers in West African health facilities. Methods Electronic databases (Medline, cumulative index to nursing and allied health literature, Centre for Agriculture and Biosciences International Global Health, EMBASE) were searched to identify original research articles from 1996 to 2016. Search terms (and synonyms) related to (1) maternal health care (e.g., obstetric care, perinatal care, maternal health services); (2) facility level (e.g., maternity unit, health facility, phase III, hospital); and (3) Western Africa (e.g., Nigeria, Burkina Faso) were combined. This review followed the preferred reporting items for systematic reviews and meta-analyses. Results Of the 2103 citations identified, 13 studies were eligible. Studies were conducted in Nigeria, Burkina Faso, Gambia, Guinea, Senegal, and Sierra Leone. 30 facility-level barriers were identified and grouped into 6 themes (human resources, supply and equipment, referral-related, infrastructure, cost-related, patient-related). The most obvious barriers included staff shortages, lack of maternal health services and procedures offered to patients, and lack of necessary medical equipment and supplies in the health-care facilities. Conclusion This review emphasizes that phase I and phase II barriers are not the only factors preventing women from accessing proper emergency obstetric care. Health-care facilities in Western Africa are inadequately equipped to handle the obstetric needs of patients. Supply-side barriers must be addressed to reduce maternal mortality in the region.

Transparency is now among almost all governments’ priorities, with a growing number of countries that have recently adopted a law on access to administrative documents. In 2014, Paraguay even became the 100th state to pass a legislation on access to information (ATI). These laws do not provide a substitute for transparency; however, they may signal the willingness of public authorities to increase openness. So far, most studies have focused on states where laws on access to administrative documents already exist (mainly in Europe and North America), while very few research has been conducted in other parts of the world. Based on previous research, this contribution presents the case of Benin in Western Africa: conditions of emergence, structures and obstacles in several states will be presented and then compared with the current situation in Benin. Research questions concentrate on the development of ATI, challenges to the introduction of a stronger law, and the administration’s main expectations towards transparency. Data were collected through interviews conducted with WANEP‐Benin (a coalition of civil society organisations), an official in charge of access to documents and several employees of the Beninese administration. Secondary data from past and current research are also used here. Findings show the influence of contextual and institutional differences on current transparency reforms, the importance of the issue of access and global awareness, and how the current approach towards access to administrative documents in Benin is influenced by the practices regarding transparency.

Background The 2014–2016 Ebola crisis in West Africa had approximately eight times as many reported deaths as the sum of all previous Ebola outbreaks. The outbreak magnitude and occurrence of multiple Ebola cases in at least seven countries beyond Liberia, Sierra Leone, and Guinea, hinted at the possibility of broad-scale transmission of Ebola. Main text Using a modeling tool developed by the US Centers for Disease Control and Prevention during the Ebola outbreak, we estimated the number of Ebola cases that might have occurred had the disease spread beyond the three countries in West Africa to cities in other countries at high risk for disease transmission (based on late 2014 air travel patterns). We estimated Ebola cases in three scenarios: a delayed response, a Liberia-like response, and a fast response scenario. Based on our estimates of the number of Ebola cases that could have occurred had Ebola spread to other countries beyond the West African foci, we emphasize the need for improved levels of preparedness and response to public health threats, which is the goal of the Global Health Security Agenda. Our estimates suggest that Ebola could have potentially spread widely beyond the West Africa foci, had local and international health workers and organizations not committed to a major response effort. Our results underscore the importance of rapid detection and initiation of an effective, organized response, and the challenges faced by countries with limited public health systems. Actionable lessons for strengthening local public health systems in countries at high risk of disease transmission include increasing health personnel, bolstering primary and critical healthcare facilities, developing public health infrastructure (e.g. laboratory capacity), and improving disease surveillance. With stronger local public health systems infectious disease outbreaks would still occur, but their rapid escalation would be considerably less likely, minimizing the impact of public health threats such as Ebola. Conclusions The Ebola outbreak could have potentially spread to other countries, where limited public health surveillance and response capabilities may have resulted in additional foci. Health security requires robust local health systems that can rapidly detect and effectively respond to an infectious disease outbreak. Electronic supplementary material The online version of this article (10.1186/s40249-017-0373-4) contains supplementary material, which is available to authorized users.

Resumen: En este trabajo los autores realizan una novedosa clasificación de las problemáticas mentales que presentan los inmigrantes negroafricanos asentados en la provincia de Almería (España). Muchos de estos cuadros presentan tal gravedad sintomática que finalmente precisan de un ingreso en la Unidad de Salud Mental del Hospital de Poniente, para allí afrontar el comienzo de su tratamiento. En esta clasificación antropológica se entrecruzan dos modelos médicos, el biomédico y el tradicional africano, y dos miradas divergentes, la de los profesionales de salud mental (etic) y la de los inmigrantes afectados y los integrantes de sus redes locales (emic). Partiendo de esta base, se describen tres cuadros diferentes: locura ancestral o síndrome negativo, locura moderna o síndrome positivo y locura tóxica o síndrome mixto. En cada una de estas tres modalidades se especifica su etiología, modo de presentación, sintomatología, evolución, pronóstico, itinerario terapéutico y efecto en la red social de referencia. Abstract: In this study, the authors carry out a new classification of the mental problems presented by black African immigrants settled in the province of Almería (Spain). In many of these cases, symptom severity is such that they eventually require admission to the Mental Health Unit of the Hospital de Poniente in order to be treated. In this anthropological classification, two medical models, the biomedical and the traditional African, and two divergent points of view, that of mental health professionals (etic) and that of the affected immigrants and the members of their local networks (emic), become intertwined. On this basis, three clinical profiles are described: ancient madness or negative syndrome, modern madness or positive syndrome, and toxic madness or mixed syndrome. The etiology of each of these three types, its mode of presentation, symptomatology, progress, prognosis, therapeutic itinerary, and its effect on the social network of reference are described..

Using a meta-synthesis approach, through the review of current literature, five published and peer reviewed qualitative research reports were studied. The intention was to identify interventions being used with West African children who have endured adverse childhood experiences. These results were found through matching inclusionary criteria and all studies were screened for appropriateness and relevance to the topic matter. The literature was analyzed across five online databases including Proquest, PsychInfo, Scopus, Wiley, and Springer from January 2005 to June 2020. The authors found minimal evidence indicating interventions used in West Africa for adverse experiences related specifically to children, but found themes related to interventions that serve West African families that include children. Findings were thematically analyzed through meta-synthesis and identified four themes used in the interventions, which include western, spiritual, expressive arts, and cultural approaches. West African children endure adverse experiences such as terrorism, abuse, and war violence that contribute to an increasing the need for mental health interventions. These experiences approached from western, spiritual, expressive arts, and cultural vantage points were identified but limited in information about delivery and efficacy, thus providing little guidance regarding further exploratory research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Clay, Jackson and Stephenson.)

Persons who died of Ebola virus disease at home in rural communities in Liberia and Guinea resulted in more secondary infections than persons admitted to Ebola treatment units. Intensified monitoring of contacts of persons who died of this disease in the community is an evidence-based approach to reduce virus transmission in rural communities.

In Burkina Faso, the national caesarean section rate is still low (2% in 2012). However, since the introduction of caesarean user fee exemption in 2006 and the availability of trained staff to perform a caesarean section in the most remote hospitals, the institutional caesareans rates have risen steadily and it is unclear whether all of these interventions are necessary. The main objective of this thesis is to identify the determinants of an optimal practice of caesarean section in three western African countries that favour access to caesarean section. The results of the work carried out in the framework of this thesis show that the level of qualification of the health personnel working in Burkina Faso hospitals and his professional experience determine globally his level of knowledge in the management of labor and complicated childbirth. . In addition, regular supervision of his work by daily review of clinical records (partograms) seems to improve his performance. The level of qualification of health personnel in Burkina Faso also influences the practice of non-medically justified caesareans. But the social environment also plays a role in this abusive practice. The results of this research show that the systematic practice of cesarean section after an anterior caesarean section is not justified in this context. The results of this thesis led to the development and implementation of a multi-faceted intervention trial aimed at reducing caesareans without medical reason in West Africa., Au Burkina Faso, le taux populationnel de césariennes reste encore faible (2% en 2012). Cependant, depuis l’exemption partielle (80%) pour les familles du paiement à l’acte en 2006, et la mise à disposition de médecins généralistes, sages-femmes et infirmiers formés à la pratique des césariennes dans les hôpitaux les plus reculés, on observe une augmentation constante des taux de césariennes dans les établissements de santé et il est difficile de savoir si toutes ces interventions sont réellement utiles. L’objectif principal de cette thèse est d’identifier les déterminants d’une césarienne de qualité en Afrique de l’Ouest pour orienter les politiques de santé reproductive dans les pays concernés. Les résultats des travaux menés dans le cadre de cette thèse montrent que le niveau de qualification du personnel de santé travaillant dans les hôpitaux du Burkina Faso et son expérience professionnelle déterminent globalement son niveau de connaissance en matière de gestion du travail et de l’accouchement compliqué. De plus, une supervision régulière de son travail semble améliorer sa performance. Le niveau de qualification du personnel de santé au Burkina Faso influence également la pratique de césariennes non médicalement justifiées. Mais l’environnement social joue aussi un rôle dans cette pratique abusive. Les résultats de cette recherche montrent enfin que la pratique systématique d’une césarienne après une césarienne antérieure n’est pas justifiée dans ce contexte. Les résultats de cette thèse ont permis de développer et de mettre en œuvre un essai d’intervention visant à réduire des césariennes sans raison médicale en Afrique de l’ouest.

This paper investigates whether Burkinabe maize farmers’ fertilizer-use decisionsare correlated with their risk and time preferences. We conducted a survey and a se-ries of hypothetical experiments on a sample of 1,500 farmers. We find that morepatient farmers do use more fertilizer, but it is only because they plant more maize (afertilizer-intensive crop) rather than because they use more fertilizer per hectare ofmaize planted. Conversely, we find no statistically significant link between risk aver-sion and fertilizer use. We use a simple two-period model, which suggests that riskaversion may indeed have an ambiguous effect on fertilizer use.

Women fish processors in Côte d’Ivoire in Western Africa face a bleak future, with fewer fish and declining incomes.

This master project on the palms (Arecaceae) of Togo and Benin represents the continuation of the floristic, taxonomic, ecologic and ethnobotanic study that the CJB leads on the native palms of Western Africa. We undertook a study dealing with floristics, structural botany, ethnobotany and phytogeography of the native palms from Togo and Benin. Our research combined the study of herbarium specimens (BENIN, BR, BRLU, G and TOGO) and the study of samples collected in the frame of our fieldwork.

Two arenaviruses were detected in pygmy mice (Mus spp.) by screening 764 small mammals in Ghana. The Natal multimammate mouse (Mastomys natalensis), the known Lassa virus reservoir, was the dominant indoor rodent species in 4 of 10 sites, and accounted for 27% of all captured rodents. No rodent captured indoors tested positive for an arenavirus.

Background Plasmodium vivax is considered to be absent from western Africa, where the prevalence of Duffy-negative red blood cell phenotype proves to be high. Several studies have, however, detected P. vivax infection cases in this part of Africa, raising the question of what is the actual prevalence of P. vivax in local populations. Methods The presence of P. vivax was investigated in a large population of healthy blood donors in Benin using microscopy, serology and molecular detection. The seroprevalence was measured with species-specific ELISA using two recombinant P. vivax proteins, namely rPvMSP1 and rPvCSP1. Specific molecular diagnosis of P. vivax infection was carried out using nested-PCR. The performances and cut-off values of both rPvCSP1 and rPvMSP1 ELISA were first assessed using sera from P. vivax-infected patients and from non-exposed subjects. Results Among 1234 Beninese blood donors, no parasites were detected when using microscopy, whereas 28.7% (354/1234) of patients exhibited had antibodies against rPvMSP1, 21.6% (266/1234) against rPvCSP1, and 15.2% (187/1234) against both. Eighty-four samples were selected for nested-PCR analyses, of which 13 were positive for P. vivax nested-PCR and all Duffy negative. Conclusion The results of the present study highlight an unexpectedly high exposure of Beninese subjects to P. vivax, resulting in sub-microscopic infections. This suggests a probably underestimated and insidious parasite presence in western Africa. While the vaccination campaigns and therapeutic efforts are all focused on Plasmodium falciparum, it is also essential to consider the epidemiological impact of P. vivax. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1620-z) contains supplementary material, which is available to authorized users.

In the family exploitations of dairy mixed-crop-livestock of West Africa the tree fills traditionally multiple functions (fertilization, food, domestic, medical, spiritual) and especially fodder by the pruning of the branches in dry season (e.g. Ptérocarpus lucens, Accacia albida…). But today, the pastorals resources are increasingly rare or difficult to access. The populations of trees are cleared up as agriculture extends. The cattle food is increasingly expensive and not very available and moreover the dairy mixed crop-livestock farmers have less space to cultivate fodder. However the demand for dairy products increase with urban growth, and each year, this request increases in dry season causing a great rise of the price of milk on the markets. The dairy production is thus confronted to a crescent quantitative and qualitative deficit of foodstuffs to face the increasing demand. In this context, the tree showed on an international scale a good potential to contribute to answer this challenge thanks to its capacity to provide a green quality fodder in any season but remains less adopted in the western area of Burkina Faso. A gang of researchers and dairy mixed crop-livestoks farmers of the West of Burkina Faso have begun a work to study and make evolve the place and the role of the fodder trees in a process of durable intensification of the family dairy farmings. A work of Co-design step by step of an agroforestery system innovating based on the introduction of fodder banks of ligneous family to high density into the exploitations is actually in hand. To answer the constraint of space, these fodder banks (BF) will be installed on reduced spaces (< 1000 m²) with a density of 25000 plants per ha, associating several species (Leuceana leucocephala, Morus alba Linn and Gliciridia sepium). During the phase of installation (~1 year), the BF will be protected from the divagation of the animals by reinforced quickset hedges of latticed fences. They are presented as an interesting complementary fodder resource in several situations. To reduce the food deficits and to support the production of milk in dry season, in the most traditional systems where fodder system of dry season is based mainly on culture residues of low quality. To reduce the purchase of food cattle (cereal bran and oil cakes) in the exploitations more intensive and more connected to the urban market. This project is innovating for this geographical area., Dans les exploitations familiales de polyculture-élevage laitier d’Afrique de l’ouest l’arbre remplit traditionnellement de multiples fonctions (fertilitaire, alimentaire, domestique, sanitaire, spirituelle) et notamment fourragère avec l’émondage des branches en saison sèche (ex. Ptérocarpus lucens, Accacia albida…). Mais aujourd’hui, les ressources pastorales sont de plus en plus rares ou difficiles d’accès. Les populations d’arbres s’éclaircissent à mesure que l’agriculture s’étend. Les aliments bétail sont de plus en plus chers et peu disponibles et de surcroit les polyculteurs-éleveurs laitiers disposent de peu d’espace pour cultiver des fourrages. Pourtant la demande en produits laitiers ne cesse de croître avec l’essor urbain, et chaque année, cette demande augmente en saison sèche provoquant une forte hausse du prix du lait sur les marchés. La production laitière est donc confrontée à un déficit quantitatif et qualitatif croissant des ressources alimentaires pour répondre à une demande en plein essor. Dans ce contexte, l’arbre a démontré à l’échelle internationale un bon potentiel pour contribuer à répondre à ce défi grâce à sa capacité à fournir un fourrage vert et de qualité en toute saison mais reste peu adopté dans la région ouest du Burkina Faso. Une équipe de chercheurs et de polyculteurs-éleveurs laitiers de l’Ouest du Burkina Faso ont donc engagé un travail pour étudier et faire évoluer la place et le rôle des arbres fourragers dans un processus d’intensification durable des élevages laitiers familiaux. Un travail de co-conception pas-à-pas d’un système agroforestier innovant basé sur l’introduction de banques fourragères de ligneux à haute densité dans les exploitations est en cours. Pour répondre à la contrainte d’espace, ces banques fourragères (BF) seront installées sur des espaces réduits (

Surveillance of Ebola virus disease flare-ups uncovers a reduced rate of Ebola virus evolution during persistent infections., On 29 June 2015, Liberia’s respite from Ebola virus disease (EVD) was interrupted for the second time by a renewed outbreak (“flare-up”) of seven confirmed cases. We demonstrate that, similar to the March 2015 flare-up associated with sexual transmission, this new flare-up was a reemergence of a Liberian transmission chain originating from a persistently infected source rather than a reintroduction from a reservoir or a neighboring country with active transmission. Although distinct, Ebola virus (EBOV) genomes from both flare-ups exhibit significantly low genetic divergence, indicating a reduced rate of EBOV evolution during persistent infection. Using this rate of change as a signature, we identified two additional EVD clusters that possibly arose from persistently infected sources. These findings highlight the risk of EVD flare-ups even after an outbreak is declared over.

Simian T-lymphotropic virus type 1 (STLV-1) strains occasionally infect humans. However, the frequency of such infections is unknown. We show that direct transmission of STLV-1 from nonhuman primates to humans may be responsible for a substantial proportion of human T-lymphotropic virus type 1 infections in rural Côte d’Ivoire, where primate hunting is common.

International audience; Sub-Saharan agriculture has been identified as vulnerable to ongoing climate change. Adaptation of agriculture has been suggested as a way to maintain productivity. Better knowledge of intra-specific diversity of varieties is prerequisites for the successful management of such adaptation. Among crops, root and tubers play important roles in food security and economic growth for the most vulnerable populations in Africa. Here, we focus on the sweet potato. The Sweet potato (Ipomoea batatas) was domesticated in Central and South America and was later introduced into Africa and is now cultivated throughout tropical Africa. We evaluated its diversity in West Africa by sampling a region extending from the coastal area of Togo to the northern Sahelian region of Senegal that represents a range of climatic conditions. Using 12 microsatellite markers, we evaluated 132 varieties along this gradient. Phenotypic data from field trials conducted in three seasons was also obtained. Genetic diversity in West Africa was found to be 18% lower than in America. Genetic diversity in West Africa is structured into five groups, with some groups found in very specific climatic areas, e.g. under a tropical humid climate, or under a Sahelian climate. We also observed genetic groups that occur in a wider range of climates. The genetic groups were also associated with morphological differentiation, mainly the shape of the leaves and the color of the stem or root. This particular structure of diversity along a climatic gradient with association to phenotypic variability can be used for conservation strategies. If such structure is proved to be associated with specific climatic adaptation, it will also allow developing strategies to adapt agriculture to ongoing climate variation in West Africa.

The hawksbill turtle is a critically endangered species that has been extensively exploited for centuries. Príncipe Island off western Africa harbours one of the species' major nesting populations in the eastern Atlantic, as well as hosting year-round foraging aggregations of juveniles, subadults and adult males. To gain insight into the population's genetic structure and relationships with regional stocks, we analysed mitochondrial DNA (mtDNA) sequences of nesting females (N = 9), foraging adult females (N = 11), adult males (N = 32), subadults (N = 15) and juveniles (N = 80). The nesting population was found to be fixed for a single haplotype (EATL), which had been previously reported in both western and eastern Atlantic hawksbill foraging sites but had no known rookery source prior to this study. Thus it is now possible to confirm the westward transoceanic movement by hawksbills originating from Príncipe Island. Our analyses demonstrated that the Príncipe Island nesting colony is genetically distinct from breeding populations in the western Atlantic and is phylogenetically linked with Indo-Pacific hawksbill clades, suggesting that Príncipe Island was most likely colonised by migrants from the Indian Ocean via the Cape of Good Hope in southern Africa. Mixed stock analyses revealed that the eastern Atlantic appears to be the primary foraging area for Príncipe hawksbills (75%) while most of the foraging juveniles in Príncipe waters originate from the Príncipe rookery (84%). Furthermore, the presence of Caribbean haplotypes at low frequencies (b 5%) suggests that eastward transatlantic movements by juveniles to distant foraging and developmental habitats also take place. Depleted hawksbill populations in the eastern Atlantic combined with the low genetic variability and high genetic distinctiveness found in the Príncipe nesting and foraging aggregations with respect to the western Atlantic, underscore the high degree of isolation and vulnerability of this eastern Atlantic stock. These characteristics are highly relevant for the development of effective conservation programmes and highlight the urgent need to consolidate international cooperation across regional boundaries