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Abstract Background Drug resistance in Plasmodium falciparum is a major threat to malaria control efforts. Pathogen genomic surveillance could be invaluable for monitoring current and emerging parasite drug resistance. Methods Data from two decades (2000–2020) of continuous molecular surveillance of P. falciparum parasites from Senegal were retrospectively examined to assess historical changes in malaria drug resistance mutations. Several known drug resistance markers and their surrounding haplotypes were profiled using a combination of single nucleotide polymorphism (SNP) molecular surveillance and whole genome sequence based population genomics. Results This dataset was used to track temporal changes in drug resistance markers whose timing correspond to historically significant events such as the withdrawal of chloroquine (CQ) and the introduction of sulfadoxine-pyrimethamine (SP) in 2003. Changes in the mutation frequency at Pfcrt K76T and Pfdhps A437G coinciding with the 2014 introduction of seasonal malaria chemoprevention (SMC) in Senegal were observed. In 2014, the frequency of Pfcrt K76T increased while the frequency of Pfdhps A437G declined. Haplotype-based analyses of Pfcrt K76T showed that this rapid increase was due to a recent selective sweep that started after 2014. Discussion (Conclusion) The rapid increase in Pfcrt K76T is troubling and could be a sign of emerging amodiaquine (AQ) resistance in Senegal. Emerging AQ resistance may threaten the future clinical efficacy of artesunate-amodiaquine (ASAQ) and AQ-dependent SMC chemoprevention. These results highlight the potential of molecular surveillance for detecting rapid changes in parasite populations and stress the need to monitor the effectiveness of AQ as a partner drug for artemisinin-based combination therapy (ACT) and for chemoprevention.

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.

Abstract Background Genetic surveillance of the Plasmodium falciparum parasite shows great promise for helping National Malaria Control Programmes (NMCPs) assess parasite transmission. Genetic metrics such as the frequency of polygenomic (multiple strain) infections, genetic clones, and the complexity of infection (COI, number of strains per infection) are correlated with transmission intensity. However, despite these correlations, it is unclear whether genetic metrics alone are sufficient to estimate clinical incidence. Methods This study examined parasites from 3147 clinical infections sampled between the years 2012–2020 through passive case detection (PCD) across 16 clinic sites spread throughout Senegal. Samples were genotyped with a 24 single nucleotide polymorphism (SNP) molecular barcode that detects parasite strains, distinguishes polygenomic (multiple strain) from monogenomic (single strain) infections, and identifies clonal infections. To determine whether genetic signals can predict incidence, a series of Poisson generalized linear mixed-effects models were constructed to predict the incidence level at each clinical site from a set of genetic metrics designed to measure parasite clonality, superinfection, and co-transmission rates. Results Model-predicted incidence was compared with the reported standard incidence data determined by the NMCP for each clinic and found that parasite genetic metrics generally correlated with reported incidence, with departures from expected values at very low annual incidence ( 10‰), parasite genetics can be used to accurately infer incidence and is consistent with superinfection-based hypotheses of malaria transmission. When transmission was

Abstract We here analyze data from the first year of an ongoing nationwide program of genetic surveillance of Plasmodium falciparum parasites in Senegal. The analysis is based on 1097 samples collected at health facilities during passive malaria case detection in 2019; it provides a baseline for analyzing parasite genetic metrics as they vary over time and geographic space. The study’s goal was to identify genetic metrics that were informative about transmission intensity and other aspects of transmission dynamics, focusing on measures of genetic relatedness between parasites. We found the best genetic proxy for local malaria incidence to be the proportion of polygenomic infections (those with multiple genetically distinct parasites), although this relationship broke down at low incidence. The proportion of related parasites was less correlated with incidence while local genetic diversity was uninformative. The type of relatedness could discriminate local transmission patterns: two nearby areas had similarly high fractions of relatives, but one was dominated by clones and the other by outcrossed relatives. Throughout Senegal, 58% of related parasites belonged to a single network of relatives, within which parasites were enriched for shared haplotypes at known and suspected drug resistance loci and at one novel locus, reflective of ongoing selection pressure.

Context and background The originality of the urban structure of Touba lies first of all in its management led by the general Khalif and its particular status of a land title which is backed by a strong uncontrolled demography combined with a strong sprawl poorly controlled. Touba's town planning policy seems to boil down to the creation of housing plots and the free choice left to the caliph for the sites for installing equipment or infrastructure, and the destination of the reserves. On the other hand, in Ziguinchor, land dynamics have become a central problem. Today, the peripheral districts, "old" areas of culture (Kandialang, Kenya, Djibock, Lyndiane and Diabir) constitute the main destinations for new arrivals (both from the city and from the depths countryside) in search of habitat plots. Goal and Objectives: The objective of this article is to show the different territorial dynamics in urban spaces with different tenure and land practices. Methodology: The methodological approach is based on the one hand on a documentary review, observation, socio-demographic surveys, and interviews. On the other hand, the use of geomatics (openstreetmap, google earth and Quantum GIS software) will be used for mapping. Results: The advantage of this approach has allowed us to characterize the land regimes of Touba and Ziguinchor, to quantify the dynamics of the two distinct land regimes, and to identify the issues and consequences of these territorial recompositions.

L’amplification démographique de la ville de Ziguinchor suscite l’extension spatiale qui s’accompagne de divers problèmes : dysfonctionnement dans l’aménagement urbain, développement de l'informalité économique et spatiale. Ces problèmes mettent en péril la viabilité économique en créant des déséquilibres entre les besoins croissants en services urbains de la population et les moyens faibles ou limités de la municipalité pour réaliser les investissements nécessaires. Cette situation rend plus alambiquée la gouvernance urbaine. Cet article, adopte un procédé de diagnostic du territoire urbain fondé sur l’analyse spatiale et celle de la territorialité des acteurs, extériorisé sous forme de prototypes spatiaux à travers les mécanismes de la géomatique. Les résultats ont permis d'abord, de faire le diagnostic territorial de la ville de Ziguinchor ; ensuite, d'exposer l'essor de l'emploi et l'importance de la géomatique dans la gestion urbaine et enfin, de faire des propositions innovantes permettant l’articulation des pratiques des différents acteurs pour une gouvernance urbaine efficiente.

Le pyoderma gangrenosum (PG) est une dermatose neutrophilique non infectieuse rare souvent méconnue. Il se présente généralement par des ulcérations cutanées inflammatoires, très douloureuses et d'évolution rapide. Il est fréquemment retrouvé dans un contexte de néoplasie, de pathologies inflammatoires digestives, rhumatologiques et/ou hématologiques. Son diagnostic est très souvent tardif après de multiples échecs thérapeutiques. Nous rapportons un cas de pyoderma gangrenosum dont le diagnostic n'a pas été criant. Un patient a été admis dans notre service pour une lésion dermatologique persistante et d'évolution défavorable malgré les débridements et l'administration d'antibiotiques. Il était suivi pour un cancer de la prostate, une hypertension artérielle et un asthme. Du fait des anomalies biologiques observées telles qu'une hyperleucocytose à polynucléaires neutrophiles avec myélémie à myélocytes et métamyélocytes, sans blastose sanguine et une anémie normochrome normocytaire, une leucémie myéloïde chronique a été évoquée chez ce patient. Elle a par la suite été infirmée devant les différents examens complémentaires non concluants. C'est ainsi que le diagnostic de PG a été évoqué et confirmé à l'examen anatomopathologique montrant un aspect histopathologique d'un tissu de granulation concordant avec un pyoderma gangrenosum et une absence de signe histologique de malignité. L'institution d'un traitement à base de corticothérapie a abouti à la guérison.

Fasting glucose (FG) and glycated hemoglobin A1c (HbA1c) perform sub-optimally in people of African origin, especially in individuals with sickle-cell trait (SCT). The purpose of this study was to compare the relationships between HbA1c, FG, and fructosamine in individuals from Senegal with and without SCT. HbA1c, FG, and fructosamine were measured in 203 adults from Senegal (100 control: 45 with type 2 diabetes (T2D); 103 SCT: 51 with T2D). Significant, positive correlations were observed between HbA1c and FG, fructosamine and FG, and fructosamine and HbA1c in both groups. The limits of agreement were inappropriately large in both groups for the Bland-Altman plots of HbA1c and FG (control: -95.97 to 83.97%; SCT: -115.9 to 91.52%), fructosamine and FG (control: -100.6 to 99.89%; SCT: -105.6 to 100.6%), and fructosamine and HbA1c (control: -52.03 to 38.98%; SCT: -88.04 to 71.41%). In both groups, the greatest proportion of subjects were considered above the clinical cut-point for hyperglycemia when fructosamine was used as the criterion (control: 33%; SCT: 44.6%), and the lowest percentage of subjects were classified as over the clinical cut-point when HbA1c was used as the criterion (control: 21%; SCT: 27.7%).Substantial disparities between HbA1c, FG, and fructosamine were observed in both groups, and these differences were exaggerated in the SCT group. Therefore, these three biomarkers should not be considered to be interchangeable measures of glycemic control. These biomarkers should be used thoughtfully, and special care should be taken when using them in individuals with SCT.

In West Africa, as in many other estuaries, enormous volumes of marine water are entering the continent. Fresh water discharge is very low, and it is commonly strongly linked to rainfall level. Some of these estuaries are inverse estuaries. During the Great Sahelian Drought (1968−1993), their hyperhaline feature was exacerbated. This paper aims to describe the evolution of the two main West African inverse estuaries, those of the Saloum River and the Casamance River, since the end of the drought. Water salinity measurements were carried out over three to five years according to the sites in order to document this evolution and to compare data with the historical ones collected during the long dry period at the end of 20th century. The results show that in both estuaries, the mean water salinity values have markedly decreased since the end of the drought. However, the Saloum estuary remains a totally inverse estuary, while for the Casamance River, the estuarine turbidity maximum (ETM) is the location of the salinity maximum, and it moves according to the seasons from a location 1−10 km downwards from the upstream estuary entry, during the dry season, to a location 40−70 km downwards from this point, during the rainy season. These observations fit with the functioning of the mangrove, the West African mangrove being among the few in the world that are markedly increasing since the beginning of the 1990s and the end of the dry period, as mangrove growth is favored by the relative salinity reduction. Finally, one of the inverse estuary behavior factors is the low fresh water incoming from the continent. The small area of the Casamance and Saloum basins (20,150 and 26,500 km² respectively) is to be compared with the basins of their two main neighbor basins, the Gambia River and the Senegal River, which provide significant fresh water discharge to their estuary.

INTRODUCTION: l'hyperthyroïdie de l'enfant semble rare et constitue un problème de par son retentissement psychosomatique. L'objectif était de faire le point sur ces aspects chez l'enfant à Dakar. METHODES: il s'agissait d'une étude multicentrique, descriptive sur 15 ans. Etaient analysés les aspects épidémiologiques, cliniques et étiologiques. RESULTATS: 239 patients sélectionnés avec une prévalence de 2.4%, un sex ratio (H/F) de 0.36, un âge moyen de 10.8 ans. À l'inclusion, il s'agissait d'un ainé de famille (26.3%), d'une croissance avancée (36.9%), retardée (12.5%), d'une corpulence insuffisante (40.1%). L'étiologie était la maladie de Basedow dans 90.3% avec un facteur psychoaffectif dans 22.1%. Sur le plan clinique, prédominaient la tachycardie (92.4%), le goitre (91.1%), l'exophtalmie (81.8%), l'amaigrissement (69.8%) avec cependant une énurésie (30.2%) et des manifestations psychiques (3.1%). Les manifestations cardiovasculaires et cutanées étaient positivement associées avec l'âge (p =0.05). Le goitre était associé au sexe féminin (p = 0.005), aux signes cardiovasculaires (p = 0.02), neuropsychiques (p = 0.03), cutanées (p = 0.03) et à la diarrhée (p = 0.03). La T4 libre était corrélée à l'âge (p = 0.007), la diarrhée (p = 0.021), l'anxiété (p = 0.024), la fréquence cardiaque (p = 0.00) et la maladie de Basedow (p = 0.04). Plus le goitre était volumineux, plus était augmentée la T4 libre (p = 0.007). CONCLUSION: l'hyperthyroïdie de l'enfant se différencie de celle de l'adulte par les facteurs d'induction, les perturbations sur la croissance et l'énurésie. L'âge et le sexe semble favoriser le tableau clinique de thyrotoxicose et les signes associés.

Two different notions of "essential" subsemimodules were introduced in the theory of semimodules over a semiring with identity, in order to generalize the same notion of "essential" submodules in the theory of modules over a ring with identity. In this paper, we introduce a new class of essential subsemimodules called weakly essential subsemimodules. We prove that this new class contains the others two kind of classes of "essential" subsemimodules. Futhermore, we studie the properties of weakly essential subsemimodules. For applications we introduce and investigate the co-hopfian semimodules with this new definition of semi-essential. [ABSTRACT FROM AUTHOR]

Thyroid abscess is a very rare disease due to its anatomical position and the physiology of the gland. It most often occurs in the immunosuppressed population. The diagnosis is easy and is based on ultrasound. However it is often unrecognised. Bacteriological examination allows to identify the germ responsible for this condition. We report the case of a Mauritanian patient living in the said country presenting with painful cervical swelling associated with fever. The diagnosis was based on ultrasound and confirmed by fluid examination. Bacteriological assessment didn't identify the cause of this condition. Patient's outcome was marked by regression of symptoms under antibiotic therapy, with normalization of the gland structure after two months. [ABSTRACT FROM AUTHOR]

Introduction: this study aims to determine the clinical and evolutionary profile of skin and soft tissue lesions in diabetics followed up at the dressing room. Methods: we conducted an observational descriptive and analytical study in the dressing room of the Marc Sankalé Diabetes Center, Dakar from 1 January to 31 December 2017. Our study focused on diabetics who were examined in the dressing room. Results: a total of 37.173 procedures were recorded at the Marc Sankalé Diabetes Center; 16.418 patients were treated in the dressing room, representing a prevalence of 14.16%. The average age of patients was 56,6 ±12 years, the sex ratio (M/F) was 0,88. Type 2 diabetes predominated (78,97%) and the average disease duration was 8.06 ± 7.9 years. The mean capillary blood glucose concentration was 2.4±1 g/l. Diabetic neuropathy was found in 72.33% of patients. Limb lesions were found in 93,98% of patients(1185 cases). The most common lesions included: ulcer (46,76%), abscess (13.46%), phlegmon (13.20%), gangrene (8.41%), erysipelas (3.78%), perforating ulcer (3.53%), intertrigo (3.95%). The lesions were be divided into infectious lesions (61,41), non-infectious lesions(33,50%), pure vascular lesions (1.57%) and mixed lesions (3.70%). Out of 1189 patients 7.57% had had osteitis. The germs found were Gram-positive bacteria (12.70%), Gram-negative bacteria (23.80%). Amputation was performed according to the topographical features of the lesion (p=0.00), the type of lesion (p=0.000), the seniority of diabetes (p=0.02), the type of diabetes (p=0.008), the presence of osteitis (p=0.006). Minor amputation was performed in 43,33% of cases, major amputation in 37.43% of cases; 70 deaths were recorded (5.89%). Conclusion: skin and soft tissue lesions were dominated by diabetic foot. Mortality is not negligible and the risk of amputation was statistically related to the topographical features of the lesion, the type of lesion, the seniority and the type of diabetes and the presence of osteitis. [ABSTRACT FROM AUTHOR]