Facteurs de risque de démence dans une population de personnes âgées sénégalaises

Description La démence est devenue un problème de santé publique. Dans le but d’une prévention, il est important de connaitre son épidémiologie au Sénégal. L’objectif de cette étude était d’identifier les facteurs de risque de démence dans une population de personnes âgées sénégalaises. MéthodesUne étude transversale a été réalisée du 01 Mars 2004 au 31 Décembre 2005 auprès d’une population de 872 personnes âgées de 55ans et plus utilisant le Centre Médicosocial et Universitaire de l’Institut de Prévoyance Retraite du Sénégal pour des soins. Par une étude en deux phases, des données sociodémographiques, sur le mode de vie, le réseau social, les antécédents ont été collectées à l’aide d’un questionnaire structuré complété par un examen clinique et une évaluation neuropsychologique. Le diagnostic de démence reposait sur des critères DSM IV-R

Evaluation and optimization of membrane feeding compared to direct feeding as an assay for infectivity

<p>Abstract</p> <p>Background</p> <p>Malaria parasite infectivity to mosquitoes has been measured in a variety of ways and setting, includind direct feeds of and/or membrane feeding blood collected from randomly selected or gametocytemic volunteers. <it>Anopheles gambiae s.l </it>is the main vector responsible of <it>Plasmodium falciparum </it>transmission in Bancoumana and represents about 90% of the laboratory findings, whereas <it>Plasmodium malariae </it>and <it>Plasmodium ovale </it>together represent only 10%.</p> <p>Materials and methods</p> <p>Between August 1996 and December 1998, direct and membrane feeding methods were compared for the infectivity of children and adolescent gametocyte carriers to anopheline mosquitoes in the village of Bancoumana in Mali. Gametocyte carriers were recruited twice a month through a screening of members of 30 families using Giemsa-stained thick blood smears. F1 generation mosquitoes issued from individual female wild mosquitoes from Bancoumana were reared in a controlled insectary conditions and fed 5% sugar solution in the laboratory in Bamako, until the feeding day when they are starved 12 hours before the feeding experiment. These F1 generation mosquitoes were divided in two groups, one group fed directly on gametocyte carriers and the other fed using membrane feeding method.</p> <p>Results</p> <p>Results from 372 <it>Plasmodium falciparum </it>gametocyte carriers showed that children aged 4–9 years were more infectious than adolescents (p = 0.039), especially during the rainy season. Data from 35 carriers showed that mosquitoes which were used for direct feeding were about 1.5 times more likely to feed (p < 0.001) and two times more likely to become infected, if they fed (p < 0.001), than were those which were used for membrane feeding. Overall, infectivity was about three-times higher for direct feeding than for membrane feeding (p < 0.001).</p> <p>Conclusion</p> <p>Although intensity of infectivity was lower for membrane feeding, it could be a surrogate to direct feeding for evaluating transmission-blocking activity of candidate malaria vaccines. An optimization of the method for future trials would involve using about three-times more mosquitoes than would be used for direct feeding.</p

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

Détermination du niveau de contamination de l'ochratoxine A (OTA) dans les fèves de cacao à l'exportation

Determination of Ochratoxin A (OTA) Levels in Exported Cocoa. This exported cocoa ochratoxin A contamination assessment target is to answer the legal dispositions and regulations. Three hundred (300) large samples of dried cocoa beans was taken according the Commission Regulation (EC) No 401/2006 and OTA was quantified by HPLC analytical methods with extraction and clean-up on immunoaffinity columns. The global result shows that 33 samples out of 300 cocoa samples have levels of OTA above 2 μg/kg that constitutes 11.04% of total cocoa production in Ivory Coast. At the port of Abidjan rejected cocao beans were evaluated to 15.65%, if the maximum authorized levels are fixed to 2 μg/kg. The result for San Pedro port showed lower levels of OTA (only 6.67%). If we consider the Ivorian regulation that the under grade cocoa bean (S/G) cannot been exported (the under grade cocoa bean (S/G) is the dry cocoa bean of which the mould rate is above 4%), the slated cocoa bean rate is above 8% and the defective rate is also above 6%. At the both ports rejected cocoa beans constitutes 9.50% (11% at Abidjan and 8% at San Pedro). This cocoa beans contamination by OTA can be controlled or reduced by the efficient implementation and vulgarization of the good cocoa production, if we identify the critical points of contamination in the cocoa chain production by ochratoxigen fungi

Rice Data Systems for Sub-Saharan Africa: Contribution to the Japan-AfricaRice Emergency Rice Project

The rice data system for sub-Saharan Africa, which is a contribution to the Japan-AfricaRice Emergency Rice Initiative, is funded by the government of Japan. The project was coordinated at the regional level by Africa Rice Center (AfricaRice) and implemented at national levels by the national focal points. Throughout the course of the project implementation, the country focal points have made substantial and active contributions to ensure a smooth coordination of the project in-country activities. The national focal points are from the national agricultural research systems (NARS) and the national agricultural statistical services (NASS) of the countries that are members of the Coalition for African Rice Development (CARD). To ensure an effective communication between the project coordination unit and the countries, an intensive networking was established, which included sending of quarterly progress reports by the countries. Overall, the implementation of the project activities went well and it demonstrated the feasibility of building long-term collaborative working relationships between several national stakeholders to sustainably develop a multipurpose rice data systems. The surveys helped the countries develop well-structured rice statistical databases. Overall, the project activities went well and the national surveys were successfully conducted in the majority of the countries leading to the development of up-to-date and accessible rice data and information. In fact, as future project activities, the country teams will work to conduct in-depth analysis of the data collected in this project to update the national rice development strategies (NRDS), conduct rice research priority setting exercises and publish papers and policy briefs. AfricaRice discussed with the main donor in Japan who accepted that in-depth analysis of the data collected can continue after 30 April 2010, to publish the data in Google Map and transform the country reports into final and more comprehensive reports

Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy: The IeDEA-West Africa HIV-2 Cohort Study.

HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART) for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework of the International epidemiological Databases to Evaluate AIDS (IeDEA).We collected data on all HIV-2 and HIV-1/HIV-2 dually seropositive patients (both ARV-naive and starting ART) and followed-up in clinical centres in the IeDEA-WA network including a total of 13 clinics in five countries: Benin, Burkina-Faso Côte d'Ivoire, Mali, and Senegal, in the West Africa region.Data was merged for 1,754 patients (56% female), including 1,021 HIV-2 infected patients (551 on ART) and 733 dually seropositive for both HIV-1 and HIV 2 (463 on ART). At ART initiation, the median age of HIV-2 patients was 45.3 years, IQR: (38.3-51.7) and 42.4 years, IQR (37.0-47.3) for dually seropositive patients (p = 0.048). Overall, 16.7% of HIV-2 patients on ART had an advanced clinical stage (WHO IV or CDC-C). The median CD4 count at the ART initiation is 166 cells/mm(3), IQR (83-247) among HIV-2 infected patients and 146 cells/mm(3), IQR (55-249) among dually seropositive patients. Overall, in ART-treated patients, the CD4 count increased 126 cells/mm(3) after 24 months on ART for HIV-2 patients and 169 cells/mm(3) for dually seropositive patients. Of 551 HIV-2 patients on ART, 5.8% died and 10.2% were lost to follow-up during the median time on ART of 2.4 years, IQR (0.7-4.3).This large multi-country study of HIV-2 and HIV-1/HIV-2 dual infection in West Africa suggests that routine clinical care is less than optimal and that management and treatment of HIV-2 could be further informed by ongoing studies and randomized clinical trials in this population

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. Methods: ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. Results: The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. Conclusions: This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.Medical Research Council of South Africa gran