Morbidity associated with sickle cell trait carriers

Background: Sickle cell trait carriers has long considered asymptomatic. This affirmation is now challenged because many patients complain of osteoarticular pain and several organic degenerative complications in particular; renal, eye and sudden death have been described. The objective of this study was to evaluate the morbidity of sickle cell trait and identify risk factors associated.Methods: This is a prospective study with duration of 16 months including 50 patients with sickle cell trait received regular visits (every 6 months) for painful events. Biological assessment was carried out systematically to eliminate rheumatic disease (CRP, ASLO, latex Waler Rose) or metabolic disorders (serum calcium, serum magnesium, and serum uric acid). A correlation between clinical and laboratory data was performed to study the relationship between morbidity observed and biological abnormalities.Results: Mean age of patients was 32 years (12-59) and mean age at diagnosis was 24 years (12-55 years). Sex ratio M/F was 0.16. Clinical symptoms were osteoarticular pain (88%), headache (86%), abdominal pain (76%), muscle cramps (70%), dizziness (56%), biliary lithiasis (6%), femoral head osteonecrosis (2%) and gross haematuria (2%). Seventeen patients (34%) had abnormal metabolic or rheumatic analysis. No risk factor associated with morbidity of patients was identified.Conclusions: This work has allowed us to find that the symptoms presented by sickle cell trait patients are dominated by painful events. This morbidity associated with porting sickle cell trait was not secondary to inflammatory or metabolic disorders or physical activity

Application of Functional Data Analysis to Identify Patterns of Malaria Incidence, to Guide Targeted Control Strategies.

We introduce an approach based on functional data analysis to identify patterns of malaria incidence to guide effective targeting of malaria control in a seasonal transmission area. Using functional data method, a smooth function (functional data or curve) was fitted from the time series of observed malaria incidence for each of 575 villages in west-central Senegal from 2008 to 2012. These 575 smooth functions were classified using hierarchical clustering (Ward's method), and several different dissimilarity measures. Validity indices were used to determine the number of distinct temporal patterns of malaria incidence. Epidemiological indicators characterizing the resulting malaria incidence patterns were determined from the velocity and acceleration of their incidences over time. We identified three distinct patterns of malaria incidence: high-, intermediate-, and low-incidence patterns in respectively 2% (12/575), 17% (97/575), and 81% (466/575) of villages. Epidemiological indicators characterizing the fluctuations in malaria incidence showed that seasonal outbreaks started later, and ended earlier, in the low-incidence pattern. Functional data analysis can be used to identify patterns of malaria incidence, by considering their temporal dynamics. Epidemiological indicators derived from their velocities and accelerations, may guide to target control measures according to patterns

Le cactus Opuntia tuna (L.) Mill. et ses formes d’usage dans la zone des Niayes au Sénégal

Opuntia tuna est une espèce bien adaptée dans la zone des Niayes au Sénégal. Sa prolifération assez rapide est due en partie à une sous exploitation suscitant ainsi un envahissement de quelques espaces agropastoraux. Dans une perspective de valorisation et de meilleure gestion de l’espèce, cette présente étude a été conduite pour comprendre les formes d’usages et de gestion de la plante par les populations locales afin de la promouvoir pour renforcer leur résilience. L’étude a porté sur cinq villages de la zone nord des Niayes auprès de petits exploitants de maraichers. Des enquêtes qualitatives par entretiens et groupes de discussion ont été conduites. Elles ont porté sur le niveau de connaissance, les pratiques et usages connus du cactus, les contraintes liées à sa présence, les solutions adoptées ou envisagées et le niveau de perception sur sa valorisation. Les résultats ont révélé de nombreux usages de la plante et de ses produits. Plus de la moitié des personnes enquêtées utilise le cactus dans le domaine agricole. L’élevage, la pharmacopée et l’alimentation sont d’autres secteurs également concernés par l’usage du cactus. Les analyses ont montré que la plupart des personnes enquêtées (94%) admettent un degré d’envahissement très élevé de Opuntia tuna. Le niveau d’envahissement pourrait être liée à la zoochorie selon 38% des hommes et 33% des femmes. La bonne adaptation de l’espèce dans la zone serait également un facteur de prolifération selon 33% des hommes et 23 % des femmes. Afin de pallier la prolifération rapide du cactus les maraichers ont développé des stratégies de gestion telles que le brulis, la coupe et le dessouchage. Une meilleure gestion de cette espèce qui présente de nombreux usages pour les maraichers de la zone des Niayes est nécessaire. De tels usages de l’espèce, valorisés davantage pourrait contribuer de façon significative à la diversification des sources de revenus des communautés locales et au développement durable de la zone des Niayes

Geo-epidemiology of malaria incidence in the Vhembe District to guide targeted elimination strategies, South-Africa, 2015-2018 : a local resurgence

DATA AVAILABILITY : The datasets analysed during the current study are available from the corresponding author on reasonable request.In South Africa, the population at risk of malaria is 10% (around six million inhabitants) and concern only three provinces of which Limpopo Province is the most affected, particularly in Vhembe District. As the elimination approaches, a finer scale analysis is needed to accelerate the results. Therefore, in the process of refining local malaria control and elimination strategies, the aim of this study was to identify and describe malaria incidence patterns at the locality scale in the Vhembe District, Limpopo Province, South Africa. The study area comprised 474 localities in Vhembe District for which smoothed malaria incidence curve were fitted with functional data method based on their weekly observed malaria incidence from July 2015 to June 2018. Then, hierarchical clustering algorithm was carried out considering different distances to classify the 474 smoothed malaria incidence curves. Thereafter, validity indices were used to determine the number of malaria incidence patterns. The cumulative malaria incidence of the study area was 4.1 cases/1000 person-years. Four distinct patterns of malaria incidence were identified: high, intermediate, low and very low with varying characteristics. Malaria incidence increased across transmission seasons and patterns. The localities in the two highest incidence patterns were mainly located around farms, and along the rivers. Some unusual malaria phenomena in Vhembe District were also highlighted as resurgence. Four distinct malaria incidence patterns were found in Vhembe District with varying characteristics. Findings show also unusual malaria phenomena in Vhembe District that hinder malaria elimination in South Africa. Assessing the factors associated with these unusual malaria phenome would be helpful on building innovative strategies that lead South Africa on malaria elimination.The A*MIDEX Foundation of Aix-Marseille University, funded by socio-economic partners.https://www.nature.com/srephj2023School of Health Systems and Public Health (SHSPH)UP Centre for Sustainable Malaria Control (UP CSMC

Correction: A Seroepidemiological Study of Serogroup A Meningococcal Infection in the African Meningitis Belt.

[This corrects the article DOI: 10.1371/journal.pone.0147928.]

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Analysis of the spatio-temporal dynamics of malaria by the approach of local detection of persistent foci

Pour accélérer le processus d’élimination du paludisme, l’OMS recommande de développer des stratégies de luttes ciblées pour intensifier la réduction de la morbidité et de la mortalité. A l’approche de la phase d’élimination, la transmission devient plus faible et spatialement hétérogène, nécessitant ainsi d’analyser le paludisme à l’échelle locale, au niveau du sous-district ou du village.Par ailleurs, l’identification de foyers de persistance du paludisme est un atout majeur pour accélérer le processus d’élimination du paludisme, grâce à des interventions ciblées. Cependant dans la littérature, la définition scientifique et les méthodes de détection des foyers ne sont pas unanimes. De plus, la localisation de ces foyers sont susceptibles de changer dans le temps dû en partie à l’évolution temporelle des facteurs environnementaux, météorologiques, entre autres, modifiant la répartition géographique du paludisme. A cet effet, une approche basée sur la méthode des données fonctionnelle a été proposée pour identifier des profils dynamiques de paludisme. Grâce à cette approche fonctionnelle, des indicateurs épidémiologiques comme le démarrage, l’accélération, le pic, le ralentissement, les moments de recrudescence et la fin de l’épidémie, ont été définis sur la base des vitesses et accélérations des profils de paludisme. La finalité était de proposer des outils permettant de guider les stratégies d’intervention par un ciblage des zones prioritaires et des dates pertinentes pour les mettre en œuvre.Ce travail de thèse a été appliqué dans deux pays de la Région africaine de l’OMS de réalités épidémiologiques et environnementales différentes: le Sénégal et l’Afrique du Sud.To accelerate the process of malaria elimination, WHO recommends developing targeted control strategies to intensify the reduction of morbidity and mortality. As the elimination phase approaches, transmission becomes low and spatially heterogeneous, thus necessitating analysis of malaria at the local level, sub-district or village.In addition, the identification of persistent malaria foci is a major asset in accelerating the process of malaria elimination through targeted interventions. However, in the literature, the scientific definition and methods of detecting foci are not unanimous. Moreover, the location of these foci are likely to change over time due in part to the temporal evolution of environmental, meteorological and other factors that modify the spatial distribution of malaria. Thus, an approach based on the functional data method has been proposed to identify dynamic malaria patterns. Thanks to this functional approach, epidemiological indicators such as onset, acceleration, peak, slowdown, moments of recrudescence and end of the epidemic were defined on the basis of the velocities and accelerations of malaria patterns. The aim was to propose tools to guide intervention strategies by targeting priority areas and relevant dates for implementation.This thesis work was applied in two countries of the WHO African Region with different epidemiological and environmental realities: Senegal and South Africa

WITHDRAWN: Power through trees. State territorialisation by means of privatization and ‘agrobizforestry’ in Côte d'Ivoire

This article has been withdrawn at the request of the Publisher. The Publisher apologizes for anyinconvenience this may cause.The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal

Lack of SARS-CoV-2 among Grand Magal de Touba pilgrims consulting for respiratory symptoms in October 2020

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