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Abstract Background Following WHO guidelines, microscopy is the gold standard for malaria diagnosis in endemic countries. The Parasitology-Mycology laboratory (LPM) is the National Reference Laboratory and is currently undergoing ISO 15189 accreditation. In this context, we assessed the performance of the laboratory by confirming the reliability and the accuracy of results obtained in accordance with the requirements of the ISO 15189 standards. This study aimed to verify the method of microscopic diagnosis of malaria at the LPM, in the Aristide Le Dantec hospital (HALD) in Dakar, Senegal. Methods This is a validation/verification study conducted from June to August 2020. Twenty (20) microscopic slides of thick/thin blood smear with known parasite densities (PD) selected from the Cheick Anta Diop University malaria slide bank in Dakar were used for this assessment. Six (6) were used to assess microscopists’ ability to determine PD and fourteen (14) slides were used for detection (positive vs negative) and identification of parasites. Four (4) LPM-HALD microscopists read and recorded their results on prepared sheets. Data analysis was done with Microsoft Excel 2010 software. Results A minimum threshold of 50% concordance was used for comparison. Of the twenty (20) slides read, 100% concordance was obtained on eight (8) detection (positive vs negative) slides. Four (4) out of the six (6) parasite density evaluation slides obtained a concordance of less than 50%. Thirteen (13) out of the fourteen (14) identification slides obtained a concordance greater than 50%. Only one (1) identification slide obtained zero agreement from the microscopists. For species identification a concordance greater than 80% was noted and the microscopists obtained scores between 0.20 and 0.4 on a scale of 0 to 1 for parasite density reading. The microscopists obtained 100% precision, sensitivity, specificity and both negative and positive predictive values. Conclusion This work demonstrated that the microscopic method of malaria diagnosis used in the LPM/HALD is in accordance with the requirements of WHO and ISO 15189. Further training of microscopists may be needed to maintain competency.

In Senegal, onions (Allium cepa L.) are an important and widely consumed crop. Several varieties and speculations are cultivated, with yields and bulbs qualities depending on technical itineraries and cultivation areas. The aim of this study is to evaluate the quality of onion bulbs produced at the Kalassane and Nguéthioro sites, using morphological and physicochemical parameters. To this end, an optimized treatment based on the “Société Nationale d’Aménagement et d’Exploitation des terres du Delta” (SAED) technical data sheet, requiring water and fertilizer inputs to be controlled (4455.4 m3 of water/ha, 9 kg/9 m2 of organic matter applied before sowing and 224 g/m2 of N- P-K applied in 4 inputs), another based on the farmers' method using excessive quantities of water and fertilizers (6526.1 m3 water/ha, 12 kg/9 m2 organic matter applied after sowing and 748 g/m2 N-P-K applied in 5 applications), and their combinations were applied on Kalassane. Next, the best method for ensuring quality bulbs at Kalassane was also tested at Nguéthioro. The results show that at Kalassane, onion bulbs from the optimized method are small (67.96 ± 14.40 g) and less waterlogged (Wc 85.44 % ± 0.71, aw 0.83 ± 0.01), with a high total polyphenol content (7.01 mg/100 g ± 0.01), in contrast to those from the farmers’ method, which are 100.80 g ± 14.22; 87.14 % ± 0.69; 0.91 ± 0.01 and 2.11 mg/100 g ± 0.01 respectively. In short, this study leads to the conclusion that optimized practice is the best treatment guaranteeing better quality. In addition, the optimized method showed a difference between the results for the two sites. In the future, repeating this experiment coupled with edaphic characteristics will enable us to determine the influence of soil on the physicochemical and nutritional quality of onions.

L’objectif de cet article est de présenter les potentiels et les limites de la cogestion des pêcheries artisanales au Sénégal. La méthode a consisté à mener un long travail d’investigation dans les différents conseils locaux de pêche artisanale (CLPA) implantés le long de la côte sénégalaise. Les outils de la collecte soumis aux acteurs de la pêche et aux dirigeants des CLPA se sont focalisés sur 40 indicateurs inspirés de la littérature scientifique. Ces indicateurs sont répartis en trois catégories : « Institutions et gouvernance », « Systèmes naturels » et « Personnes et moyens de subsistance ». Ils couvrent toutes les dimensions de la cogestion telle que mise en oeuvre au Sénégal. L’analyse révèle que les CLPA peinent à assumer pleinement le rôle de leadership qui leur est assigné par l’État et leur base sociale. Compte tenu de leur dépendance financière vis-à-vis de l’État et des partenaires de développement, leur capacité d’influence reste faible et leur positionnement sociopolitique, limité. Cette faible affirmation à l’échelle locale est également liée à la fragilité de leur base organisationnelle, qui compromet finalement leur performance économique et écologique. Le cadre de gouvernance locale est marqué par la superposition de plusieurs entités locales (groupements d’intérêt économique [GIE] et associations) sans coordination qui évoluent dans une logique de concurrence. Malgré ces limites d’ordre principalement organisationnel et économique, la cogestion de la pêche artisanale présente des potentialités. En plus de se positionner comme un nouveau cadre local pour la gestion des pêches, les CLPA ont entamé une recomposition de l’architecture institutionnelle locale et constituent des espaces de construction d’initiatives techniques (pour la durabilité des ressources halieutiques) et socioéconomiques (pour l’amélioration des moyens d’existence des acteurs de la pêche). Globalement, la gouvernance des pêches au Sénégal est partagée entre une gestion directive qui s’effrite progressivement et une nouvelle forme, la cogestion, qui tarde à s’imposer efficacement.

The objective of this article is to present the potential and limits of the co-management of artisanal fisheries in Senegal. The method consisted of carrying out extensive investigation work in the various local artisanal fishing councils (CLPAs) established along the Senegalese coast. The interview guide and questionnaire submitted to fishery stakeholders and CLPA leaders focused on 40 indicators inspired by scientific literature. These indicators are divided into three categories : "governance", "natural systems" and "populations and livelihoods". They cover all dimensions of co-management as implemented in Senegal. The analysis reveals that the CLPAs struggle to fully assume the leadership role assigned to them by the State and their social base. Given their financial dependence on the State and development partners, they have little capacity for influence and limited socio-political positioning. This weak self-assertion at the local level is also linked to the fragility of their organizational base, which ultimately compromises their economic and ecological performance. The local governance framework is characterized by the superposition of several local entities (economic interest groups [EIG] and associations) that lack any coordination and operate in a logic of competition. Despite these limitations, which are mainly organizational and economic in nature, the co-management of artisanal fishing has potential. Beyond positioning themselves as a new local framework for fishery management, the CLPAs have started restructuring the local institutional architecture and offer spaces where to build initiatives, both technical (to ensure the sustainability of fishery resources) and socioeconomic (to improve the livelihoods of fishing stakeholders). Overall, the governance of fisheries in Senegal is split into a directive management framework which is gradually crumbling and a new style (co-management) which is slow to take hold. [ABSTRACT FROM AUTHOR]

Over recent decades, the Senegalese artisanal fisheries have undergone major innovations in response to fishing policies and fluctuations in fish abundance. This article addresses the adequacy of public policies regarding the constraints and challenges in the fisheries sector with a view to integrating innovations into decision-making processes. Since these changes are essentially due to economic factors, we addressed the issue mainly from an economic angle. Our results demonstrate that attempts to modernize the artisanal fisheries by replacing for example the traditional canoes by semi-industrial boats have failed. In fact, the ability of artisanal fishers to adopt new innovations and more effective strategies was able to guarantee a greater viability and resilience of their activities. More generally, their adaptability allowed them to suitably react to various exogenous shocks related to the economic aspects as well as to the variability of fish abundance and demand. These adaptive interactions between natural capital and human capital which govern the development of the artisanal fisheries support the notion of 'weak sustainability' in the field of marine fisheries. [ABSTRACT FROM AUTHOR]

Abstract Background Malaria control and elimination strategies are based on levels of transmission that are usually determined by data collected from health facilities. In endemic areas, asymptomatic Plasmodium infection is thought to represent the majority of infections, though they are not diagnosed nor treated. Therefore, there might be an underestimation of the malaria reservoir, resulting in inadequate control strategies. In addition, these untreated asymptomatic Plasmodium infections maintain transmission, making it difficult or impossible to reach malaria elimination goals. Thus, the aim of this study was to determine the prevalence of asymptomatic Plasmodium infections in southeastern Senegal. Methods A cross sectional study was conducted among asymptomatic individuals (N = 122) living in the village of Andiel located in Bandafassi, Kédougou, which consisted of about 200 inhabitants during the malaria transmission season in late October 2019. For each individual without malaria-related symptoms and who consented to participate, a rapid diagnostic test (RDT) was performed in the field. Results were confirmed in the laboratory with photo-induced electron transfer (PET-PCR). Results Malaria prevalence was 70.3% by PET-PCR and 41.8% by RDT. During the same period, the health post of the area reported 49. 1% test positivity rate by RDT. The majority of the infected study population, 92.9%, was infected with a single species and 7.1% had two or three species of Plasmodium. Plasmodium falciparum was predominant and represented 90.2% of the infections, while 6.5% were due to Plasmodium ovale and 3.3% to Plasmodium malariae. 59.4% of children targeted for SMC (zero to ten years old) were infected. Conclusion In southeastern Senegal, where the transmission is the highest, malaria control strategies should address asymptomatic Plasmodium infections at the community level. The results suggest that this area could be eligible for mass drug administration. Moreover, non-falciparum species could be more common and its prevalence should be determined countrywide.

The objective of this article is to analyze the issues related to the marketing of coastal pelagics in Senegal. Available information shows that in terms of nutritional conditions and poverty alleviation, small coastal pelagics are of strategic importance in Senegal. However, the emergence of new non-food uses and the trend of pelagic exports (growing global demand) threaten national food security and the sustainability of stocks. Unlike coastal demersal fish, where exclusive contracts are concluded between fishermen, fishmongers and fish processors, for coastal pelagics market mechanisms prevail, with landed fish being sold daily to the highest bidder. Faced with more attractive external markets, the apparent availability of fish products for the Senegalese population is consequently decreasing.

Small pelagics are the main fish resource in North West Africa. In Senegal, these are mainly sardinellas ( Sardinella aurita and S. maderensis ) and bonga shad ( Ethmalosa fimbriata ). The fisheries, mainly encircling gillnets and purse seines, are predominantly performed by artisanal fishers and are of great importance for the Senegalese economy and for food security in the region. However, in recent years, the main conditions for these fisheries have changed and recent observations have shown strong declines in profit. An analysis over the last twenty years (1993–2013) show that the fisheries lost profit between 65% and 100% while operating costs increased by 25% and 90%, for encircling gillnet and purse seine, respectively. While the fuel price dominates as determining factor during the survey period, important other drivers during the last five years were a decrease in fish biomass and an increase in fishing effort. [ABSTRACT FROM AUTHOR]

This paper assesses the level of implementation of co-management in the governance of Marine Protected Areas (MPAs) in Senegal. Fieldwork (perception surveys and interviews) was carried out with local stakeholders in seven of Senegal's MPAs from 2016 to 2018, supported by a conceptual analysis of the various dimensions of MPAs governance. The article highlights the difficulties induced by the implementation of the participatory approach in the management of MPAs in Senegal, and how these difficulties question the very performance of MPAs. The shortcomings identified include management committees’ lethargy, the existence of a duality between participatory management and directive governance, and finally, the difficulty in correctly executing management measures. The main results allow us to make recommendations for optimizing the management of MPAs. After fifteen years of operation, it seems that the governance framework of protected areas needs to be strengthened in Senegal, in order to have stronger, dynamic and unifying local institutions in order to achieve their objectives of conservation and to sustainably implement natural resources community management.

Background: Emergence and spread of drug resistance to every anti-malarial used to date, creates an urgent need for development of sensitive, specific and field-deployable molecular tools for detection and surveillance of validated drug resistance markers. Such tools would allow early detection of mutations in resistance loci. The aim of this study was to compare common population signatures and drug resistance marker frequencies between two populations with different levels of malaria endemicity and history of anti-malarial drug use: Tanzania and Sénégal. This was accomplished by implementing a high resolution melting assay to study molecular markers of drug resistance as compared to polymerase chain reaction–restriction fragment length polymorphism (PCR/RFLP) methodology. Methods: Fifty blood samples were collected each from a lowly malaria endemic site (Sénégal), and a highly malaria endemic site (Tanzania) from patients presenting with uncomplicated Plasmodium falciparum malaria at clinic. Data representing the DHFR were derived using both PCR–RFLP and HRM assay; while genotyping data representing the DHPS were evaluated in Senegal and Tanzania using HRM. Msp genotyping analysis was used to characterize the multiplicity of infection in both countries. Results: A high prevalence of samples harbouring mutant DHFR alleles was observed in both population using both genotyping techniques. HRM was better able to detect mixed alleles compared to PCR/RFLP for DHFR codon 51 in Tanzania; and only HRM was able to detect mixed infections from Senegal. A high prevalence of mutant alleles in DHFR (codons 51, 59, 108) and DHPS (codon 437) were found among samples from Sénégal while no mutations were observed at DHPS codons 540 and 581, from both countries. Overall, the frequency of samples harbouring either a single DHFR mutation (S108N) or double mutation in DHFR (C59R/S108N) was greater in Sénégal compared to Tanzania. Conclusion: Here the results demonstrate that HRM is a rapid, sensitive, and field-deployable alternative technique to PCR–RFLP genotyping that is useful in populations harbouring more than one parasite genome (polygenomic infections). In this study, a high levels of resistance polymorphisms was observed in both dhfr and dhps, among samples from Tanzania and Sénégal. A routine monitoring by molecular markers can be a way to detect emergence of resistance involving a change in the treatment policy.

Background: The use of artemisinin as a monotherapy resulted in the emergence of artemisinin resistance in 2005 in Southeast Asia. Monitoring of artemisinin combination therapy (ACT) is critical in order to detect and prevent the spread of resistance in endemic areas. Ex vivo studies and genotyping of molecular markers of resistance can be used as part of this routine monitoring strategy. One gene that has been associated in some ACT partner drug resistance is the Plasmodium falciparum multidrug resistance protein 1 (pfmdr1) gene. The purpose of this study was to assess the drug susceptibility of P. falciparum populations from Thiès, Senegal by ex vivo assay and typing molecular markers of resistance to drug components of ACT currently used for treatment. Methods: The ex vivo susceptibility of 170 P. falciparum isolates to chloroquine, amodiaquine, lumefantrine, artesunate, and artemether was determined using the DAPI ex vivo assay. The high resolution melting technique was used to genotype the pfmdr1 gene at codons 86, 184 and 1246. Results: A significant decrease in IC50 values was observed between 2012 and 2013: from 13.84 to 6.484 for amodiaquine, 173.4 to 113.2 for lumefantrine, and 39.72 to 18.29 for chloroquine, respectively. Increase of the wild haplotype NYD and the decrease of the mutant haplotype NFD (79 and 62.26 %) was also observed. A correlation was observed between the wild type allele Y184 in pfmdr1 and higher IC50 for all drugs, except amodiaquine. Conclusion: This study has shown an increase in sensitivity over the span of two transmission seasons, marked by an increase in the WT alleles at pfmdr1. Continuous the monitoring of the ACT used for treatment of uncomplicated malaria will be helpful.

Background: The Senegalese National Malaria Control Programme has recommended use of rapid diagnostic tests (RDTs) that target the histidine-rich protein 2 (HRP2), specific to Plasmodium falciparum, to diagnose malaria cases. The target antigen has been shown to be polymorphic, which may explain the variability in HRP2-based RDT results reported in field studies. The genetic diversity of the pfhrp2 gene has not been investigated in depth in many African countries. The goal of this study is to determine the extent of polymorphism in pfhrp2 among Senegal, Mali and Uganda parasite populations, and discuss the implications of these findings on the utility of RDTs that are based on HRP2 detection. Methods: Sequencing data from the pfhrp2 locus were used to analyze the genetic diversity of this gene among three populations, with different transmission dynamics and malaria parasite ecologies. Nucleotide diversity (π) and non-synonymous nucleotide diversity (πNS) were studied in the pfhrp2 gene from isolates obtained in Senegal. Amino acid repeat length polymorphisms in the PfHRP2 antigen were characterized and parameters of genetic diversity, such as frequency and correlation between repeats in these populations, were assessed. Results: The diversity survey of the pfhrp2 gene identified 29 SNPs as well as insertion and deletion polymorphisms within a 918 bp region. The Senegal pfhrp2 exhibited a substantial level of diversity [π = 0.00559 and πNS = 0.014111 (πS = 0.0291627)], similar to several polymorphic genes, such as msp1, involved in immune responses, and the gene encoding the SURFIN polymorphic antigen, which are surface exposed parasite proteins. Extensive repeat length polymorphisms in PfHRP2, as well as similar patterns in the number, organization and the type of predicted amino acid repeats were observed among the three populations, characterized by an occurrence of Type 2, Type 4 and Type 7 repeats. Conclusions: These results warrant deeper monitoring of the RDT target antigen diversity and emphasize that development of other essential genes as a target for diagnostic tools is critical.

Octopus vulgaris is fished by both small-scale and industrial fleets and has great social and economic value. Octopuses are fished in intertidal and subtidal areas using various fishing gear, with trawling used by industrial fleets and hand jigs, pots, traps, and trammel nets used by small-scale fleets. Over the years, the octopus has consistently been one of the most important commercial cephalopod resources in Senegal. Given the high economic value of octopus in Senegal, this paper discusses octopus management, as well as the industry's direct impacts on the biological traits of octopus. Survey data reveals that there are some differences in the octopus management preferences within Mbour; however, in general, fishers support biological rest and the use of octopus spawning pots. This study examines the socioeconomic importance of octopus and their management by scientifically analyzing the octopus fishery in Senegal. Octopuses have a short life span (12–14 months), grow rapidly, and have high natural mortality due to its sensitivity to environmental conditions. Therefore, the abundance index decreased from 13.7 kg per days at sea in 1999 to 3.3 kg per days at sea in 2016 due to seasonal fluctuations. Meanwhile, landing volumes notably increased from 2980 t in 1997 to 5932 t in 2016. Octopuses are typically destined for the European and Asian markets, with an export volume of 4886 t and gross revenue of US$26 million in 2016. However, this species is fully exploited, demonstrating the need for increased involvement of fishers in the management decision-making process. • Octopus is fully-exploited by small-scale and industrial fishing. • Biological rest is the ideal measure for octopus protection. • Octopus is a short life span and large variations of landing volumes. • The price fluctuations depend on the weight and size of the species. • The increase in the income is due to the variation of season. [ABSTRACT FROM AUTHOR]