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Kedougou, Senegal's southeastern region, is a substantial arbovirus hotspot (1,2). Decades of comprehensive surveillance have existed through both a nationwide Syndromic Sentinel Surveillance Network (3) and passive surveillance in several [...]

The recent stall in the global reduction of malaria deaths has made the development of a highly effective vaccine essential. A major challenge to developing an efficacious vaccine is the extensive diversity of Plasmodium falciparum antigens. While genetic diversity plays a major role in immune evasion and is a barrier to the development of both natural and vaccine-induced protective immunity, it has been under-prioritized in the evaluation of malaria vaccine candidates. This study uses genomic approaches to evaluate genetic diversity in next generation malaria vaccine candidate PfRh5. We used targeted deep amplicon sequencing to identify non-synonymous Single Nucleotide Polymorphisms (SNPs) in PfRh5 (Reticulocyte-Binding Protein Homologue 5) in 189 P. falciparum positive samples from Southern Senegal and identified 74 novel SNPs. We evaluated the population prevalence of these SNPs as well as the frequency in individual samples and found that only a single SNP, C203Y, was present at every site. Many SNPs were unique to the individual sampled, with over 90% of SNPs being found in just one infected individual. In addition to population prevalence, we assessed individual level SNP frequencies which revealed that some SNPs were dominant (frequency of greater than 25% in a polygenomic sample) whereas most were rare, present at 2% or less of total reads mapped to the reference at the given position. Structural modeling uncovered 3 novel SNPs occurring under epitopes bound by inhibitory monoclonal antibodies, potentially impacting immune evasion, while other SNPs were predicted to impact PfRh5 structure or interactions with the receptor or binding partners. Our data demonstrate that PfRh5 exhibits greater genetic diversity than previously described, with the caveat that most of the uncovered SNPs are at a low overall frequency in the individual and prevalence in the population. The structural studies reveal that novel SNPs could have functional implications on PfRh5 receptor binding, complex formation, or immune evasion, supporting continued efforts to validate PfRh5 as an effective malaria vaccine target and development of a PfRh5 vaccine.

Introduction : Le beurre de karité, riche en acides gras, est devenu un excipient de choix dans l'industrie des produits topiques en raison de ses propriétés uniques. L’objectif de ce travail est d’étudier les propriétés émulsionnantes du beurre de karité produit au Mali. Méthodologie : Il s’est agi d’une étude expérimentale et descriptive sur le beurre de karité de la région de Bougouni. Une méthode de balayage unidimensionnel a été utilisée pour déterminer les proportions optimales de beurre permettant de former des émulsions stables avec de l'eau, sans l'ajout d'agents de stabilisation. Les tests ont varié de 0 à 90% d'eau, avec des incréments de 10%, et ont été répliqués. Résultats : À la fin de la préparation, les émulsions avec des proportions de beurre/eau de 90/10, 80/20, 70/30 et 30/70 ont été stables et fluides 2 heures après l'émulsification. En revanche, les crèmes avec des proportions de 60/40, 50/50 et 40/60 ont été stables et épaisses. Toutes les émulsions ont eu une apparence blanche laiteuse, une consistance semi- solide à solide, et des globules d'une taille de 1 à 5 µm, correspondant à une émulsion moyenne. Toutes avaient été de type E/H. Après 90 jours, les crèmes de proportions 90/10, 80/20, 70/30, 60/40, 50/50 et 40/60 ont été les plus stables, indiquant que le beurre de karité peut incorporer jusqu'à 60% d'eau sans instabilité. Conclusion : le beurre de karité malien, riche en acides oléiques et stéariques, présente des propriétés émulsionnantes et peut incorporer jusqu'à 60% d'eau sans montrer de signes d'instabilité après 90 jours. Ce qui pourrait faire de ce produit, un co-émulsifiant accessible économiquement et permettant de réduire les coûts de fabrication de certains produits.

Introduction : L’acné est l’un des motifs de consultations les plus fréquents dans les services de Dermatologie. Pour renforcer la prise en charge de l’acné, il est possible d’exploiter les données d’efficacité, de sécurité et de qualité de trois des plantes citées sur 21 plantes recensées en l’Afrique de l’Ouest. L’objectif est le développement puis la fabrication d’un savon dermo-pharmaceutique efficace et accessible économiquement à la majorité des patients de l’Hôpital de Dermatologie de Bamako. Méthodologie : Les échantillons des feuilles de Lawsonia inermis, du gel des bulbes de l’Aloès vera et de l’huile des graines d’Azadirachta indica ont été apprêtés au niveau Département de Médecine Traditionnelle de Bamako. La formulation a été réalisée au niveau de l’unité galénique de l’Hôpital de Dermatologie de Bamako. Le procédé de fabrication à froid a été adopté. Les ingrédients et leurs pourcentages sont : Beurre de Karité (23,6) / Huile de palmiste (17,7) / Huile végétale de Neem (17,7) / Gel d’Aloe Vera (5,9)/ Poudre du Henné (3) / Soude caustique (8,7) / Eau (20,4) / H.E d’Eucalyptus (1,8) / Jus de citron (1,2). La formule du savon a été développée selon le logiciel calculateur de saponification « Soaphomemade ». Le savon a été fabriqué et sa qualité physico-chimique a été déterminée. L’enquête de satisfaction a été réalisée par 10 testeurs hommes et femmes, sains, résidant à Bamako. La durée des tests était de 15 jours et les propriétés recherchées étaient le pouvoir moussant, nettoyant, exfoliant et émollient, aussi l’odeur et les recommandations. Le prix du savon a été estimé et comparé aux autres vendus en pharmacie. Résultats : Trois lots de savon de 6 morceaux de 75 g ont été fabriqués. Les savons avaient une couleur Brun foncé, avec des pH autour de 8 et étaient durs. L’odeur était caractéristique de l’huile de neem. Les savons respectaient toutes les normes de qualité selon le calculateur de saponification. 80% des testeurs étaient globalement satisfaits du produit. Le coût de fabrication a été estimé à 950 F CFA comparé aux savons : Mitracca 1300 F CFA ; Vegebom Purifiant 2000 F CFA ; Laino au soufre2350 F CFA ; Nobacter 3100 F CFA. Conclusion : Une étude sensorielle auprès de 10 testeurs/res a été satisfaisante. En perspective, il s’agira de valider ces résultats préliminaires chez un nombre important de patients.

During the 2018-2020 Ebola virus disease (EVD) outbreak in North Kivu province in the Democratic Republic of Congo, EVD was diagnosed in a patient who had received the recombinant vesicular stomatitis virus-based vaccine expressing a ZEBOV glycoprotein (rVSV-ZEBOV) (Merck). His treatment included an Ebola virus (EBOV)-specific monoclonal antibody (mAb114), and he recovered within 14 days. However, 6 months later, he presented again with severe EVD-like illness and EBOV viremia, and he died. We initiated epidemiologic and genomic investigations that showed that the patient had had a relapse of acute EVD that led to a transmission chain resulting in 91 cases across six health zones over 4 months. (Funded by the Bill and Melinda Gates Foundation and others.).

Human enteroviruses (HEVs) are ubiquitous and responsible for a spectrum of acute diseases in humans, including aseptic meningitis, encephalitis, acute flaccid paralysis, myocarditis, type 1 diabetes, and neonatal enteroviral sepsis [...]

Objective: Crimean‐Congo haemorrhagic fever (CCHF) is a severe zoonotic arboviral disease that occurs widely in Eastern and Western Europe, Asia and Africa. The disease is becoming of growing public health importance in Senegal. However, analysis of tick infestation, CCHF virus (CCHFV) circulation extent and risk factors during ongoing outbreak are scarce. A thorough outbreak investigation was carried out during a CCHF outbreak in Podor (Northern Senegal) in August 2022. Methods: Ticks and blood samples were collected from animals (cattle, goats and sheep) randomly selected from confirmed CCHF human cases houses, neighbourhoods and surrounding villages. Blood samples were tested for CCHFV antibodies using a commercial enzyme‐linked immunosorbent assay (ELISA) test. Tick samples were screened for CCHFV RNA by RT‐PCR. Results: Overall, tick infestation rate (TIR) and CCHFV seroprevalence of livestock were 52.12% (95% confidence interval (CI): 45.54%–58.64%) and 43.28% (95% CI: 36.33%–50.44%), respectively. The TIRs were 87.7% in cattle, 57.6% in sheep and 20.0% in goats. These rates were significantly associated with location, host species and tick control (p < 0.001) but not with animal age and sex (p > 0.7). CCHFV seroprevalence was 80.4% (95% CI: 67.57%–89.77%) in cattle, 35.4% (95% CI: 25.00%–47.01%) in sheep and 21.2% (95% CI: 12.11%–33.02%) in goats. Age, sex, location, animal host and presence of ticks were significantly associated to the presence of antibodies. The 950 ticks collected included among other species, Hyalomma impeltatum (48.84%) and H. rufipes (10.21%). Five pools of Hyalomma ssp. were found CCHFV RT‐PCR positive. These infected ticks included 0.86% (4/464) of H. impeltatum collected on cattle and sheep and 1.03% (1/97) of H. rufipes collected on a sheep. Conclusions: To our knowledge, this is the first report on the extend of tick infestation and CCHFV infection in livestock during an outbreak in Senegal. The results highlight the risk of human infections and the importance of strengthening vector, animal and human surveillance as well as tick control measures in this area to prevent CCHF infections in humans. [ABSTRACT FROM AUTHOR]

In Guinea, the index coronavirus disease (COVID-19) case-patient identified on March 12, 2020, was an expatriate traveling back from Europe. Immediately, a COVID-19 task force was established by the Agence [...]

The 2013-2016 West African epidemic caused by the Ebola virus was of unprecedented magnitude, duration and impact. Here we reconstruct the dispersal, proliferation and decline of Ebola virus throughout the region by analysing 1,610 Ebola virus genomes, which represent over 5% of the known cases. We test the association of geography, climate and demography with viral movement among administrative regions, inferring a classic 'gravity' model, with intense dispersal between larger and closer populations. Despite attenuation of international dispersal after border closures, cross-border transmission had already sown the seeds for an international epidemic, rendering these measures ineffective at curbing the epidemic. We address why the epidemic did not spread into neighbouring countries, showing that these countries were susceptible to substantial outbreaks but at lower risk of introductions. Finally, we reveal that this large epidemic was a heterogeneous and spatially dissociated collection of transmission clusters of varying size, duration and connectivity. These insights will help to inform interventions in future epidemics.

On 1 August 2018, the Democratic Republic of the Congo (DRC) declared its tenth Ebola virus disease (EVD) outbreak. To aid the epidemiologic response, the Institut National de Recherche Biomédicale (INRB) implemented an end-to-end genomic surveillance system, including sequencing, bioinformatic analysis and dissemination of genomic epidemiologic results to frontline public health workers. We report 744 new genomes sampled between 27 July 2018 and 27 April 2020 generated by this surveillance effort. Together with previously available sequence data (n = 48 genomes), these data represent almost 24% of all laboratory-confirmed Ebola virus (EBOV) infections in DRC in the period analyzed. We inferred spatiotemporal transmission dynamics from the genomic data as new sequences were generated, and disseminated the results to support epidemiologic response efforts. Here we provide an overview of how this genomic surveillance system functioned, present a full phylodynamic analysis of 792 Ebola genomes from the Nord Kivu outbreak and discuss how the genomic surveillance data informed response efforts and public health decision making. Phylogeographic analysis of 792 Ebola virus genomes from the 2018 oubreak in the Democratic Republic of the Congo integrated into an end-to-end surveillance program demonstrates the feasibility of using genomic sequencing data to inform the public health epidemic response in near-real time., Author(s): Eddy Kinganda-Lusamaki [sup.1] [sup.2] , Allison Black [sup.3] [sup.4] , Daniel B. Mukadi [sup.2] , James Hadfield [sup.4] , Placide Mbala-Kingebeni [sup.1] [sup.2] , Catherine B. Pratt [sup.5] , [...]

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Background: Chronic ulcers of the lower limb (CULL) are characterized by non-healing skin loss, often associated with vascular, neurological, infectious, traumatic, or tumoral factors. These ulcers are prevalent, recurrent, severe, and have significant socio-economic implications. While Western data show a higher prevalence among women and the elderly, with varying rates (0.10% to 0.80%), developing countries, especially in sub-Saharan Africa, report a higher prevalence among young men due to infectious causes. Despite their impact, CULL often lacks attention from health authorities, resulting in delays in medical consultation. This study aims to share experiences in understanding the epidemioclinical aspects and management of CULL. Objective: The objective was to offer a comprehensive overview of the epidemiological and clinical characteristics and treatment strategies for chronic lower limb ulcers observed at the University Hospital Center of Dermatology in Bamako. Patients and Methods: Conducted at the Dermatology and Venereology Department of the University Hospital Center of Dermatology in Bamako, this cross-sectional study spanned a period from January to December 2021. It included 520 patients, with 22.1% having chronic ulcers of the lower limbs. Males (52.2%) were predominant, with an average age of 42.4 years. Trauma triggered 73.0% of the cases, and more than half waited over a year before seeking medical help. Bacteriological examinations revealed microbial infections in 67.8% of the cases. Results: There was a 22.1% prevalence of chronic lower limb ulcers among the 520 patients. Males represented 52.2%, with a median age of 42.4 years. Trauma was the primary trigger in 73.0% of the cases. Bacteriological examinations identified various infections, with 67.8% being infectious in origin. There were diverse characteristics in size, shape, and edge conditions of the ulcers. Trauma was the leading factor in 73.0% of the cases. Bacteriological examinations identified Gram-negative bacilli, Staphylococcus aureus, Streptococcus, with 67.8% of the ulcers being infectious in origin. There was outpatient treatment in 64.3% of the cases. Therapies included postural drainage, venotonics, vasculoprotectors, analgesics, compression stockings, and surgical interventions. Antibiotic therapy based on antibiograms for infectious ulcers. There was maintenance treatment with delayed penicillin in recurrent cases; successful skin grafting in 80.9% of cases, with 40.8% achieving complete healing in less than three months. [ABSTRACT FROM AUTHOR]

Ebolavirus disease (EVD) is an often‐lethal disease caused by the genus Ebolavirus (EBOV). Although vaccines are being developed and recently used, outbreak control still relies on a combination of various factors, including rapid identification of EVD cases. This allows rapid patient isolation and control measure implementation. Ebolavirus diagnosis is performed in treatment centers or reference laboratories, which usually takes a few hours to days to confirm the outbreak or deliver a clear result. A fast and field‐deployable molecular detection method, such as the isothermal amplification recombinase‐aided amplification (RAA), could significantly reduce sample‐to‐result time. In this study, a RT‐RAA assay was evaluated for EBOV detection. Various primer and probe combinations were screened; analytical sensitivity and cross‐specificity were tested. A total of 40 archived samples from the 2014 to 2016 Ebola outbreak in West Africa were tested with both the reference method real‐time RT‐PCR and the established RT‐RAA assay. The assay could detect down to 22.6 molecular copies per microliter. No other pathogens were detected with the Ebolavirus RT‐RAA assay. Testing 40 samples yield clinical sensitivity and specificity of 100% each. This rapid isothermal RT‐RAA assay can replace the previous RT‐RPA and continue to offer rapid EBOV diagnostics. [ABSTRACT FROM AUTHOR]

Dugbe virus (DUGV) is a tick-borne arbovirus first isolated in Nigeria in 1964. It has been detected in many African countries using such diverse methods as serological tests, virus isolation, and molecular detection. In Senegal, reports of DUGV isolates mainly occurred in the 1970s and 1980s. Here, we report a contemporary detection of three novel DUGV isolates upon screening of a total of 2877 individual ticks regrouped into 844 pools. The three positive pools were identified as Amblyomma variegatum, the main known vector of DUGV, collected in the southern part of the country (Kolda region). Interestingly, phylogenetic analysis indicates that the newly sequenced isolates are globally related to the previously characterized isolates in West Africa, thus highlighting potentially endemic, unnoticed viral transmission. This study was also an opportunity to develop a rapid and affordable protocol for full-genome sequencing of DUGV using nanopore technology. The results suggest a relatively low mutation rate and relatively conservative evolution of DUGV isolates. [ABSTRACT FROM AUTHOR]