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Introduction: Human papilloma virus testing is a new method of screening for precancerous cervical lesions. Here we identified factors associated to the positive Human papilloma virus-testing in the context of cervical precancer screening at the Souro Sanou National Teaching Hospital in Burkina Faso. Materials and method: Conducted from June 2021-May 2022, this was a cross-sectional study, including patients aged between 25 and 55 years-old and screened for precancerous lesions and received HPV-testing at the Department of Gynecology, Obstetrics and Reproductive Medicine (DGORM) of the SSNTH. The proportion of positive HPV-test was calculated, and we identified factors associated to positive HPV-test using logistic regression. Results: Of the 759 patients came for precancerous lesions screening, 559 patients were included. Their mean-age was 38.8 ± 7.9 years-old, 94.3% were from urban area and 50.3% identified as housewives. Regarding the past medical history, it noted: number of gestures (3.2 ± 2.0), parity (2.8 ± 1.9), number of living children (2.8 ± 1.9), having abortion experience (24.0%), age of first-sexual-intercourse(18.6 ± 2.3 years), alcohol (9.1%) and tobacco (1.0%) consumption, sexually-transmitted-infection (27.0%), Human immunodeficiency virus (HIV)infection (5.0%); none had been vaccinated against HPV. Biologically, 16.6% [95% CI: 13.6–20] of the women had a positive HPV-test. The factors significantly associated with positive HPV-test were: occupation in the private sector [OR: 0.06(0.0–0.5); p < 0.001], having a sexually-transmitted-infection [OR: 3.9(2.0–7.7); p < 0.001], age of first-sexual-intercourse [OR: 0.7(0.6–0.9); p < 0.001], sexual-multiple-partnership [OR: 17.5(8.1–39.6); p < 0.001], and HIV status [OR: 13.2(4.4–40.5); p < 0.001]. Conclusion: These results call for health actions through the reinforcement for behavioral change mainly about sexually-transmitted-infections, and for the raising awareness of the population for the screening related to the precancerous lesions and HIV. [ABSTRACT FROM AUTHOR]

Noroviruses are the second leading cause of death in children under the age of 5 years old. They are responsible for 200 million cases of diarrhoea and 50,000 deaths in children through the word, mainly in low-income countries. The objective of this review was to assess how the prevalence and genetic diversity of noroviruses have been affected by the introduction of rotavirus vaccines in Africa. PubMed, Web of Science and Science Direct databases were searched for articles. All included studies were conducted in Africa in children aged 0 to 5 years old with gastroenteritis. STATA version 16.0 software was used to perform the meta-analysis. The method of Dersimonian and Laird, based on the random effects model, was used for the statistical analyses in order to estimate the pooled prevalence's at a 95% confidence interval (CI). Heterogeneity was assessed by Cochran's Q test using the I2 index. The funnel plot was used to assess study publication bias. A total of 521 studies were retrieved from the databases, and 19 were included in the meta-analysis. The pooled norovirus prevalence's for pre- and post-vaccination rotavirus studies were 15% (95 CI, 15–18) and 13% (95 CI, 09–17) respectively. GII was the predominant genogroup, with prevalence of 87.64% and 91.20% respectively for the pre- and post-vaccination studies. GII.4 was the most frequently detected genotype, with rates of 66.84% and 51.24% respectively for the pre- and post-vaccination studies. This meta-analysis indicates that rotavirus vaccination has not resulted in a decrease in norovirus infections in Africa. [ABSTRACT FROM AUTHOR]

Sorghum production system in the semi-arid region of Africa is characterized by low yields which are generally attributed to high rainfall variability, poor soil fertility, and biotic factors. Production constraints must be well understood and quantified to design effective sorghum-system improvements. This study uses the state-of-the-art in silico methods and focuses on characterizing the sorghum production regions in Mali for drought occurrence and its effects on sorghum productivity. For this purpose, we adapted the APSIM-sorghum module to reproduce two cultivated photoperiod-sensitive sorghum types across a latitude of major sorghum production regions in Western Africa. We used the simulation outputs to characterize drought stress scenarios. We identified three main drought scenarios: (i) no-stress; (ii) early pre-flowering drought stress; and (iii) drought stress onset around flowering. The frequency of drought stress scenarios experienced by the two sorghum types across rainfall zones and soil types differed. As expected, the early pre-flowering and flowering drought stress occurred more frequently in isohyets < 600 mm, for the photoperiod-sensitive, late-flowering sorghum type. In isohyets above 600 mm, the frequency of drought stress was very low for both cultivars. We quantified the consequences of these drought scenarios on grain and biomass productivity. The yields of the highly-photoperiod-sensitive sorghum type were quite stable across the higher rainfall zones > 600 mm, but was affected by the drought stress in the lower rainfall zones < 600 mm. Comparatively, the less photoperiod-sensitive cultivar had notable yield gain in the driest regions < 600 mm. The results suggest that, at least for the tested crop types, drought stress might not be the major constraint to sorghum production in isohyets > 600 mm. The findings from this study provide the entry point for further quantitative testing of the Genotype × Environment × Management options required to optimize sorghum production in Mali. [ABSTRACT FROM AUTHOR]

Does ambient infrastructural quality affect foreign direct investment (FDI) in developing countries? This paper investigates how the arrival of high-speed internet in Africa triggered FDI into the region. It also explores the role of complementary infrastructure, such as access to electricity and road connectivity, in amplifying the impact of internet connectivity on investment. To causally estimate impacts, the paper exploits plausibly exogenous variations in access to high-speed internet induced by the staggered arrival of submarine fiber-optic internet cables and spatial variations in terrestrial fiber cable networks across locations on the continent. Findings from the paper indicate that access to high-speed internet induces FDI, particularly in the service sector, with the finance, technology, retail, and health services subsectors as the main beneficiaries. Access to (hard) infrastructure, such as electricity and roads, amplifies the impact of internet connectivity on FDI, thus highlighting the role of complementarities in the impact of infrastructure. Further, the results suggest that improvement in quality of governance and increased performance of incumbent firms are plausible mechanisms. [ABSTRACT FROM AUTHOR]

Negative stereotypes about Africa abound in American schools and in the media, making it virtually impossible for newly arrived African students, whether immigrants or refugees, to accomplish their goals of getting a quality education. African students arrive on American shores with vibrant hope and expectancy that their American education will surpass even their wildest dreams. However, once they have encountered the typical American school setting their hopes of getting this exalted education are quickly dashed. In this article, the author presents the findings of a study that examined the schooling experiences of recently arrived students from Africa. Findings reveal that schooling in America was not what these students expected, and the way they were received and perceived was demoralizing and denigrating. The relationship between the African and African American students at Jackson, the site of this study, was described as openly "hostile." Jackson High has about 2,000 students, 88% African American and about 200 newly arrived students from eight different countries on the continent of Africa.

Antimicrobial resistance (AMR) is a growing global public health threat. Furthermore, wastewater is increasingly recognized as a significant environmental reservoir for AMR. Wastewater is a complex mixture of organic and inorganic compounds, including antibiotics and other antimicrobial agents, discharged from hospitals, pharmaceutical industries, and households. Therefore, wastewater treatment plants (WWTPs) are critical components of urban infrastructure that play a vital role in protecting public health and the environment. However, they can also be a source of AMR. WWTPs serve as a point of convergence for antibiotics and resistant bacteria from various sources, creating an environment that favours the selection and spread of AMR. The effluent from WWTPs can also contaminate surface freshwater and groundwater resources, which can subsequently spread resistant bacteria to the wider environment. In Africa, the prevalence of AMR in wastewater is of particular concern due to the inadequate sanitation and wastewater treatment facilities, coupled with the overuse and misuse of antibiotics in healthcare and agriculture. Therefore, the present review evaluated studies that reported on wastewater in Africa between 2012 and 2022 to identify knowledge gaps and propose future perspectives, informing the use of wastewater-based epidemiology as a proxy for determining the resistome circulating within the continent. The study found that although wastewater resistome studies have increased over time in Africa, this is not the case in every country, with most studies conducted in South Africa. Furthermore, the study identified, among others, methodology and reporting gaps, driven by a lack of skills. Finally, the review suggests solutions including standardisation of protocols in wastewater resistome works and an urgent need to build genomic skills within the continent to handle the big data generated from these studies. [ABSTRACT FROM AUTHOR]

Stage at diagnosis is an important metric in treatment and prognosis of cancer, and also in planning and evaluation of cancer control. For the latter purposes, the data source is the population-based cancer registry (PBCR), but, although stage is usually among the variables collected by cancer registries, it is often missing, especially in low-income settings. Essential TNM has been introduced to facilitate abstraction of stage data by cancer registry personnel, but the accuracy with which they can do so is unknown. 51 cancer registrars from 20 countries of sub-Saharan Africa (13 anglophone, 7 francophone) were tasked with abstracting stage at diagnosis, using Essential TNM, from scanned extracts of case. The panel comprised 28 records of each of 8 common cancer types, and the participants chose how many to attempt (between 48 and 128). Stage group (I-IV), derived from the eTNM elements that they assigned to each cancer, was compared with a gold standard, as decided by two expert clinicians. The registrars assigned the correct stage (I-IV) in between 60 and 80% of cases, with the lowest values for ovary, and the highest for oesophagus. The weighted kappa statistic suggested a moderate level of agreement between participant and expert (0.41–0.60) for 5 cancers, and substantial agreement (0.61–0.80) for three, with the best for cervix, large bowel, oesophagus and ovary, and the worst (weighted kappa 0.46) for non-Hodgkin lymphoma (NHL). For all except NHL, early stage (I/II) and late stage (III/IV) was correctly identified in 80% or more of the cases. A single training in staging using Essential TNM resulted in an accuracy that was not much inferior to what has been observed in clinical situations in high income settings. Nevertheless, some lessons were learned on how to improve both the guidelines for staging, and the training course. [ABSTRACT FROM AUTHOR]

To ensure continued food security and economic development in Africa, it is very important to address and adapt to climate change. Excessive dependence on rainfed agricultural production makes Africa more vulnerable to climate change effects. Weather information and services are essential for farmers to more effectively survive the increasing occurrence of extreme weather events due to climate change. Weather information is important for resource management in agricultural production and helps farmers plan their farming activities in advance. Machine Learning is one of the technologies used in agriculture for weather forecasting and crop disease detection among others. The objective of this study is to develop Machine Learning-based models adapted to the context of daily weather forecasting for Rainfall, Relative Humidity, and Maximum and Minimum Temperature in Senegal. In this study, we made a comparison of ten Machine Learning Regressors with our Ensemble Model. These models were evaluated based on Mean Absolute Error, Mean Squared Error, Root Mean Squared Error and Coefficient of Determination. The results show that the Ensemble Model performs better than the ten base models. The Ensemble Model results for each parameter are as follows; Relative Humidity: Mean Absolute Error was 4.0126, Mean Squared Error was 29.9885, Root Mean Squared Error was 5.4428 and Coefficient of Determination was 0.9335. For Minimum Temperature: Mean Absolute Error was 0.7908, Mean Squared Error was 1.1329, Root Mean Squared Error was 1.0515 and Coefficient of Determination was 0.9018. For Maximum Temperature: Mean Absolute Error was 1.2515, Mean Squared Error was 2.8038, Root Mean Squared Error was 1.6591 and Coefficient of Determination was 0.8205. For Rainfall: Mean Absolute Error was 0.2142, Mean Squared Error was 0.1681, Root Mean Squared Error was 0.4100 and Coefficient of Determination was 0.7733. From the present study, it has been observed that the Ensemble Model is a feasible model to be used for Rainfall, Relative Humidity, and Maximum and Minimum Temperature forecasting. [ABSTRACT FROM AUTHOR]

Introduction: to help reduce neonatal mortality in Burkina Faso, we identified the prognostic factors for neonatal mortality at the Sourô Sanou University Hospital. Methods: we conducted a cross-sectional and analytical study in the neonatal department from July 25, 2019 to June 25, 2020. Patients' medical records, consultation and hospital records were reviewed. Prognostic factors for neonatal mortality were identified using a Cox model. Results: data from 1128 newborn babies were analysed. Neonatal mortality was 29.8%. Most of these deaths (89%) occurred in the early neonatal period. The mean weight of newborns at the admission was 2,285.8 ± 878.7 and 43.6%. They were at a healthy weight. Four out of five newborns had been hospitalized for infection or prematurity. The place of delivery (HR weight <1000g = 5.45[3.81 -7.79]) and the principal diagnosis (HR asphyxiation= 1.64[1.30-2.08]) were prognostic factors for neonatal mortality. Conclusion: improving technical facilities for the etiological investigation of infections and an efficient management of low-weight newborns suffering from respiratory distress would considerably reduce in-hospital neonatal mortality in Bobo-Dioulasso. [ABSTRACT FROM AUTHOR]

Powdery mildew disease caused by Oidium arachidis poses a threat to peanut production in Africa. Loss of function mutants of specific Mlo (Mildew Locus O) genes have provided broad-spectrum and durable resistance against pathogen in many crop species. Since there is huge potential to utilize susceptibility gene-mediated resistance in crop improvement, genome-wide mining of susceptibility genes is required for further researches. However, the susceptibility genes have not been characterized in peanut genome. In this research study, the genome of the cultivated peanut was used as reference to identify the AhMlo loci. Our results revealed that 25 AhMlo loci were identified and distributed on the chromosomes of the cultivated peanut. Eleven AhMlo loci were located on the A-genome while the remaining 14 on the B-genome. Variable number of inserted intron sequences (4–14) and transmembrane helix (4–8) were observed in the coding sequence of the AhMlo loci. Furthermore, phylogenetic analysis of the AhMlo loci along with homologs from other species has clustered the AhMlo loci into six clades. Three AhMlo loci were clustered in the clade V known to regroup the powdery susceptibility loci in dicots. Additionally, four core promoters were predicted on the promoter region of the specific AhMlo along with cis-regulatory elements related to PM susceptibility. These results provided strong evidence of the identification and distribution of the Mlo loci in the cultivated peanut genome and the identified specific AhMlo loci can be used for loss of susceptibility study. [ABSTRACT FROM AUTHOR]

Being able to visualize biology at the molecular level is essential for our understanding of the world. A structural biology approach reveals the molecular basis of disease processes and can guide the design of new drugs as well as aid in the optimization of existing medicines. However, due to the lack of a synchrotron light source, adequate infrastructure, skilled persons and incentives for scientists in addition to limited financial support, the majority of countries across the African continent do not conduct structural biology research. Nevertheless, with technological advances such as robotic protein crystallization and remote data collection capabilities offered by many synchrotron light sources, X‐ray crystallography is now potentially accessible to Africa‐based scientists. This leap in technology led to the establishment in 2017 of BioStruct‐Africa, a non‐profit organization (Swedish corporate ID: 802509‐6689) whose core aim is capacity building for African students and researchers in the field of structural biology with a focus on prevalent diseases in the African continent. The team is mainly composed of, but not limited to, a group of structural biologists from the African diaspora. The members of BioStruct‐Africa have taken up the mantle to serve as a catalyst in order to facilitate the information and technology transfer to those with the greatest desire and need within Africa. BioStruct‐Africa achieves this by organizing workshops onsite at our partner universities and institutions based in Africa, followed by post‐hoc online mentoring of participants to ensure sustainable capacity building. The workshops provide a theoretical background on protein crystallography, hands‐on practical experience in protein crystallization, crystal harvesting and cryo‐cooling, live remote data collection on a synchrotron beamline, but most importantly the links to drive further collaboration through research. Capacity building for Africa‐based researchers in structural biology is crucial to win the fight against the neglected tropical diseases, e.g. ascariasis, hookworm, trichuriasis, lymphatic filariasis, active trachoma, loiasis, yellow fever, leprosy, rabies, sleeping sickness, onchocerciasis, schistosomiasis, etc., that constitute significant health, social and economic burdens to the continent. BioStruct‐Africa aims to build local and national expertise that will have direct benefits for healthcare within the continent. [ABSTRACT FROM AUTHOR]

Information on the mycotoxin contamination of rice in Africa is limited although the risk of contamination is high. In this study, domestic milled rice processed by actors using suboptimal methods was purchased and total fumonisin (FUM), zearalenone, and aflatoxin concentrations determined at 0, 90, and 180 days after storage. Three different climatic locations, Cotonou (Benin) in the Guinea savanna, Yaoundé (Cameroon) in the Tropical forest, and N'diaye (Senegal) in the Sahel, were selected as storage sites. Subsets of the samples collected from Glazoue (Benin), Ndop (Cameroon), and Dagana (Senegal) were stored in plastic woven bags under room conditions in the respective sites with or without calcium oxide (burnt scallop shell—BSS, 0.1% w/w) treatment. Multivariance analysis showed that FUM concentration was positively influenced by the duration of storage only while zearalenone concentration was negatively influenced by relative humidity and head rice but positively by impurities. Zearalenone concentration was also influenced by sample collection/storage location, processing type, and duration of storage. Aflatoxin concentration was influenced negatively by storage room temperature and head rice but positively by impurities and chalky grains. In addition, aflatoxin concentration was influenced by collection/storage location and processing type. BSS treatment followed by storage for 6 months had no effect on the concentration of the three assessed mycotoxins. Strategies to reduce the risk of mycotoxin contamination in study sites will include the improvement of physical rice quality through better pre‐ and postharvest practices and proper packaging of both treated rice and untreated rice in hermetic systems before marketing and storage. [ABSTRACT FROM AUTHOR]

Background: Worldwide, nearly 570,000 women are diagnosed with cervical cancer each year, with 85% of new cases in low- and middle-income countries. The African continent is home to 35 of 40 countries with the highest cervical cancer mortality rates. In 2014, a partnership involving a rural region of Senegal, West Africa, was facing cervical cancer screening service sustainability barriers and began adapting regional-level policy to address implementation challenges. Objective: This manuscript reports the findings of a systematic literature review describing the implementation of decentralized cervical cancer prevention services in Africa, relevant in context to the Senegal partnership. We report barriers and policy-relevant recommendations through Levesque's Patient-Centered Access to Healthcare Framework and discuss the impact of this information on the partnership's approach to shaping Senegal's regional cervical cancer screening policy. Methods: The systematic review search strategy comprised two complementary sub-searches. We conducted an initial search identifying 4272 articles, then applied inclusion criteria, and ultimately 19 studies were included. Data abstraction focused on implementation barriers categorized with the Levesque framework and by policy relevance. Results: Our findings identified specific demand-side (clients and community) and supply-side (health service-level) barriers to implementation of cervical cancer screening services. We identify the most commonly reported demand- and supply-side barriers and summarize salient policy recommendations discussed within the reviewed literature. Conclusions: Overall, there is a paucity of published literature regarding barriers to and best practices in implementation of cervical cancer screening services in rural Africa. Many articles in this literature review did describe findings with notable policy implications. The Senegal partnership has consulted this literature when faced with various similar barriers and has developed two principal initiatives to address contextual challenges. Other initiatives implementing cervical cancer visual screening services in decentralized areas may find this contextual reporting of a literature review helpful as a construct for identifying evidence for the purpose of guiding ongoing health service policy adaptation. [ABSTRACT FROM AUTHOR]

Up to now, the control of malaria remains a challenge. The World Health Organization (WHO) recommends the use of artemisinin-based combination therapies (ACTs) for uncomplicated malaria treatment. Despite this guideline, many people in Burkina Faso use herbal medicine as primary treatment against malaria. The aim of this study was to assess the in vivo activity of Guiera senegalensis J. F. Gmel and Bauhinia rufescens Lam. leaves extracts against Plasmodium berghei ANKA. A four-day treatment of leaves decoction of each plant was administrated orally to 7 groups of six NMRI (Naval Medical Research Institute) mice infected with Plasmodium berghei ANKA strain. The control group received distilled water as treatment while the treated groups each received daily 100, 250, and 500 mg extract/kg body weight. Thin blood smears were performed on day five and the percentage of reduction of parasitaemia was determined compared to the control. The percentages of reduction of the parasitaemia at the doses of 100, 250, and 500 mg extract/kg body weight were, respectively, 57.5%, 35.9%, and 44.9% for Guiera senegalensis and 50.6%, 22.2%, and 25.7% for Bauhinia rufescens. Our findings on antiplasmodial activity of these two plants justify the traditional use by local populations against malaria. Thus, the isolation of the active compounds from these two plants is suggested for possible antimalarial candidate drugs. [ABSTRACT FROM AUTHOR]

Herbaceous plants account for more than three-fourths of the total biomass in savanna ecosystems. However, which environmental factors mainly drive the biodiversity of herbaceous species is still under debate. In this study, we investigated the influence of climate, habitat and land use on species richness and cover in the West African savanna ecosystems of Burkina Faso. For a broader understanding, we analysed responses of the most important taxonomical groups of the herbaceous layer (Poaceae, Cyperaceae, Fabaceae s.l. and juvenile woody species) to the above mentioned environmental factors. We found light limitation by trees or shrubs and nutrient availability to be the variables that were mainly able to explain the differences in species richness, whereas precipitation and soil water-holding capacity, in general, drive species cover. However, specifically which environmental parameters influenced species richness and cover differed between taxonomical groups. Species richness of Cyperaceae species depended on water availability, while high Cyperaceae cover was found in soils with high water-holding capacity. Cyperaceae species are able to tolerate stagnant water. By contrast, Poaceae species cover was higher in dry habitats, and species richness declined with higher mean annual precipitation. Fabaceae species richness and cover were both higher in communal areas and sandy soils. This study revealed that both species richness and species cover, important aspects to describe the community composition, should be examined, as they are driven by sometimes different environmental conditions. Differentiating between the most important taxonomical groups of the savanna ecosystem increases the understanding in the important ecological processes that effect the herbaceous vegetation composition. [ABSTRACT FROM AUTHOR]

Background: The objective was to evaluate the safety and immunogenicity of the AMA1-based malaria vaccine FMP2.1/ AS02A in children exposed to seasonal falciparum malaria. Methodology/Principal Findings: A Phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02A is a recombinant protein (FMP2.1) based on apical membrane antigen 1 (AMA1) from the 3D7 clone of P. falciparum, formulated in the Adjuvant System AS02A. The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert®). One hundred healthy Malian children aged 1-6 years were recruited into 3 cohorts and randomized to receive either 10 μg FMP2.1 in 0.1 mL AS02A, or 25 μg FMP2.1 in 0.25 mL AS02A, or 50 μg FMP2.1 50 μg in 0.5 mL AS02A, or rabies vaccine. Three doses of vaccine were given at 0, 1 and 2 months, and children were followed for 1 year. Solicited symptoms were assessed for 7 days and unsolicited symptoms for 30 days after each vaccination. Serious adverse events were assessed throughout the study. Transient local pain and swelling were common and more frequent in all malaria vaccine dosage groups than in the comparator group, but were acceptable to parents of participants. Levels of anti-AMA1 antibodies measured by ELISA increased significantly (at least 100-fold compared to baseline) in all 3 malaria vaccine groups, and remained high during the year of follow up. Conclusion/Significance: The FMP2.1/AS02A vaccine had a good safety profile, was well-tolerated, and induced high and sustained antibody levels in malaria-exposed children. This malaria vaccine is being evaluated in a Phase 2 efficacy trial in children at this site. Trial Registration: ClinicalTrials.gov NCT00358332 [http://clinicaltrials.gov/ct2/show/NCT00358332] [ABSTRACT FROM AUTHOR]

Background: Reductions in malaria incidence in Africa can largely be attributed to increases in malaria vector control activities; predominately the use of long-lasting insecticidal nets (LLINs). With insecticide resistance affecting an increasing number of malaria-endemic countries and threatening the effectiveness of conventional LLINs, there is an increasing urgency to implement alternative tools that control these resistant populations. The aim of this study was to identify potential challenges and opportunities for accelerating access to next-generation LLINs in Burkina Faso, a country with areas of high levels of insecticide resistance.Methods: An analytical framework was used to guide the selection of interviewees, data collection and analysis. Semi-structured interviews were carried out with key informants in April 2014 in Burkina Faso. Interviews were conducted in French and English, audio recorded, transcribed and entered into NVivo 10 for data management and analysis. Data were coded according to the framework themes and then analysed to provide a description of the key points and explain patterns in the data.Results: Interviewees reported that the policy architecture in Burkina Faso is characterised by a strong framework of actors that contribute to policymaking and strong national research capacity which indirectly contributes to national policy change via collaboration with internationally led research. Financing significantly impacts the potential adoption, availability and affordability of next-generation LLINs. This confers significant power on international donors that fund vector control. National decisions around which LLINs to procure were restricted to quantity and delivery dates; the potential to tackle insecticide resistance was not part of the decision-making process. Furthermore, at the time of the study, there was no World Health Organization (WHO) guidance on where and when next-generation LLINs might positively impact on malaria transmission, severely limiting their adoption, availability and affordability.Conclusions: This study shows that access to next-generation LLINs was severely compromised by the lack of global guidance. In a country like Burkina Faso where WHO recommendations are relatively quickly adopted, a clear WHO recommendation and adequate financing will be key to accelerate access to next-generation LLINs. [ABSTRACT FROM AUTHOR]

The success of a systematic review depends on the availability, accessibility and quality of literature related to the review question. This paper presents the literature found in four systematic reviews conducted for a selection of zoonotic hazards in four livestock value chains in Africa, as well as setting out the challenges in conducting the reviews. The protocol was designed following international standards, and addressed four questions around prevalence, risk factors, control options and impact of various hazards and populations. Searches were conducted in four online databases. Articles were screened for relevance, and quality was assessed before data extraction. Literature on zoonotic hazards was in general scarce and access to full articles was limited. Overall, 25-40% of papers were considered poor quality. The diversity of approaches and designs in the studies compromised the ability to generate summarized estimates. We found that the emphasis of veterinary research has been on livestock problems rather than public health issues, although this seems to be shifting in the last decade; we also found there are limited studies on impact and control. While increasing literature is being published around zoonoses in Africa, this is still inadequate to appropriately inform policy and guide research efforts. [ABSTRACT FROM AUTHOR]

Daniellia oliveri is a common plant in Africa and widely used by the population. It is found in the wooded savannahs as well as in dry forests. The medicinal properties of Daniellia oliveri are attributed to its different parts. Thus the leaves are used to treat various diseases such as inflammation, fever and pain. The comparative study of the aqueous extract of leaves Daniellia oliveri and the indomethacin (INDOCID) on inflammation induced by carrageenan on the right hind paw of the rats showed antiinflammatory properties of this extract. The phytochemical analysis of the aqueous extract of leaves Daniellia oliveri showed the presence of flavonoids which could cause anti-inflammatory properties of this extract. The toxicological study of aqueous extract of leaves of Daniellia oliveri allowed to determine an LD50 = 436.51 mg/kg body weight. According Classification of Diezi this plant is toxic. These results justify the traditional use of leaves of Daniellia oliveri as anti-inflammatory. [ABSTRACT FROM AUTHOR]

Background: Entomological indicators are considered key metrics to document the interruption of transmission of Onchocerca volvulus, the etiological agent of human onchocerciasis. Human landing collection is the standard employed for collection of the vectors for this parasite. Recent studies reported the development of traps that have the potential for replacing humans for surveillance of O. volvulus in the vector population. However, the key chemical components of human odor that are attractive to vector black flies have not been identified. Methodology/Principal Findings: Human sweat compounds were analyzed using GC-MS analysis and compounds common to three individuals identified. These common compounds, with others previously identified as attractive to other hematophagous arthropods were evaluated for their ability to stimulate and attract the major onchocerciasis vectors in Africa (Simulium damnosum sensu lato) and Latin America (Simulium ochraceum s. l.) using electroantennography and a Y tube binary choice assay. Medium chain length carboxylic acids and aldehydes were neurostimulatory for S. damnosum s.l. while S. ochraceum s.l. was stimulated by short chain aliphatic alcohols and aldehydes. Both species were attracted to ammonium bicarbonate and acetophenone. The compounds were shown to be attractive to the relevant vector species in field studies, when incorporated into a formulation that permitted a continuous release of the compound over time and used in concert with previously developed trap platforms. Conclusions/Significance: The identification of compounds attractive to the major vectors of O. volvulus will permit the development of optimized traps. Such traps may replace the use of human vector collectors for monitoring the effectiveness of onchocerciasis elimination programs and could find use as a contributing component in an integrated vector control/drug program aimed at eliminating river blindness in Africa. Author Summary: Human landing collections, which are the current standard for collecting the black fly vectors of Onchocerca volvulus, the causative agent of river blindness, are inefficient and pose certain ethical issues. As entomological methods are among the primary techniques recommended by the international community for verifying the elimination of onchocerciasis, there is a need to develop alternative methods to collect these vectors. Recent studies have demonstrated that traps baited with CO2 and dirty clothing have the potential to replace human landing collections for this purpose. However, for these traps to be widely applied, it will be necessary to develop a consistent bait formulation. To this end, volatile compounds from human sweat that attract the principal black fly vectors of O. volvulus in Africa and the Americas have been identified and used to optimize traps that specifically collect these insects. To achieve this milestone, we report the use of electroantennography and behavioral assays to identify human compounds that are neurostimulatory to these vectors, and demonstrate that these compounds are attractive to the vectors in field studies using previously developed trap platforms. The development of such a defined bait formulation will permit the widespread use of these traps by onchocerciasis elimination programs in Africa and the Americas. [ABSTRACT FROM AUTHOR]

Light and water use by vegetation at the ecosystem level, are key components for understanding the carbon and water cycles particularly in regions with high climate variability and dry climates such as Africa. The objective of this study is to examine recent trends over the last 30 years in Light Use Efficiency (LUE) and inherent Water Use Efficiency (iWUE*) for the major biomes of Africa, including their sensitivities to climate and CO2. LUE and iWUE* trends are analyzed using a combination of NOAA-AVHRR NDVI3g and fAPAR3g, and a data-driven model of monthly evapotranspiration and Gross Primary Productivity (based on flux tower measurements and remote sensing fAPAR, yet with no flux tower data in Africa) and the ORCHIDEE (ORganizing Carbon and Hydrology In Dynamic EcosystEms) process-based land surface model driven by variable CO2 and two different gridded climate fields. The iWUE* data product increases by 10%-20% per decade during the 1982-2010 period over the northern savannas (due to positive trend of vegetation productivity) and the central African forest (due to positive trend of vapor pressure deficit). In contrast to the iWUE*, the LUE trends are not statistically significant. The process-based model simulations only show a positive linear trend in iWUE* and LUE over the central African forest. Additionally, factorial model simulations were conducted to attribute trends in iWUE and LUE to climate change and rising CO2 concentrations. We found that the increase of atmospheric CO2 by 52.8 ppm during the period of study explains 30%-50% of the increase in iWUE* and >90% of the LUE trend over the central African forest. The modeled iWUE* trend exhibits a high sensitivity to the climate forcing and environmental conditions, whereas the LUE trend has a smaller sensitivity to the selected climate forcing. [ABSTRACT FROM AUTHOR]

Background The opportunities for developing new drugs and vaccines for malaria control look brighter now than ten years ago. However, there are few places in sub-Saharan Africa with the necessary infrastructure and expertise to support such research in compliance to international standards of clinical research (ICH-GCP). The Clinical Research Unit of Nanoro (CRUN) was founded in 2008 to provide a much-needed GCP-compliant clinical trial platform for an imminent large-scale Phase 3 malaria vaccine trial. A dynamic approach was used that entailed developing the required infrastructure and human resources, while engaging local communities in the process as key stakeholders. This provided a better understanding and ownership of the research activities by the local population. Case description Within five years (2008-2013), the CRUN set up a fully and well-equipped GCP-compliant clinical trial research facility, which enabled to attract 25 grants. The research team grew from ten health workers prior to 2008 to 254 in 2013. A Health and Demographic Surveillance System (HDSS), which covers a total population of about 60,000 people in 24 villages was set up in the district. The local community contributed to the development of the facility through the leadership of the king and the mayor of Nanoro. As a result of their active advocacy, the government extended the national electrical grid to the new research center, and later to the entire village. This produced a positive impact on the community's quality of life. The quality of health care improved substantially, due to the creation of more elaborate clinical laboratory services and the acquisition of state-of-the-art equipment. Conclusion Involving the community in the key steps of establishing the centre provided the foundation for what was to become the CRUN success story. This experience demonstrates that when clinical trials research sites are carefully developed and implemented, they can have a positive and powerful impact on local communities in resource-poor settings, well beyond the task of generating expected study data. [ABSTRACT FROM AUTHOR]

It is difficult to assess pollution in remote areas of less-developed regions owing to the limited availability of energy, equipment, technology, trained personnel and other key resources. Passive sampling devices (PSDs) are technologically simple analytical tools that sequester and concentrate bioavailable organic contaminants from the environment. Scientists from Oregon State University and the Centre Régional de Recherches en Ecotoxicologie et de Sécurité Environnementale (CERES) in Senegal developed a partnership to build capacity at CERES and to develop a pesticide-monitoring project using PSDs. This engagement resulted in the development of a dynamic training process applicable to capacity-building programmes. The project culminated in a field and laboratory study where paired PSD samples were simultaneously analysed in African and US laboratories with quality control evaluation and traceability. The joint study included sampling from 63 sites across six western African countries, generating a 9000 data point pesticide database with virtual access to all study participants. [ABSTRACT FROM AUTHOR]

Background: Mass treatment with ivermectin controls onchocerciasis as a public health problem, but it was not known if it could also interrupt transmission and eliminate the parasite in endemic foci in Africa where vectors are highly efficient. A longitudinal study was undertaken in three hyperendemic foci in Mali and Senegal with 15 to 17 years of annual or six-monthly ivermectin treatment in order to assess residual levels of infection and transmission, and test whether treatment could be safely stopped. This article reports the results of the final evaluations up to 5 years after the last treatment. Methodology/Principal Findings: Skin snip surveys were undertaken in 131 villages where 29,753 people were examined and 492,600 blackflies were analyzed for the presence of Onchocerca volvulus larva using a specific DNA probe. There was a declining trend in infection and transmission levels after the last treatment. In two sites the prevalence of microfilaria and vector infectivity rate were zero 3 to 4 years after the last treatment. In the third site, where infection levels were comparatively high before stopping treatment, there was also a consistent decline in infection and transmission to very low levels 3 to 5 years after stopping treatment. All infection and transmission indicators were below postulated thresholds for elimination. Conclusion/Significance: The study has established the proof of principle that onchocerciasis elimination with ivermectin treatment is feasible in at least some endemic foci in Africa. The study results have been instrumental for the current evolution from onchocerciasis control to elimination in Africa. Author Summary: The control of onchocerciasis, or river blindness, is based on annual or six-monthly treatment with ivermectin of populations at risk. This has been effective in controlling the disease as a public health problem but it was not known whether it could also eliminate infection and transmission to the extent that treatment could be safely stopped. Many doubted that this was feasible in Africa. A study was undertaken in three hyperendemic onchocerciasis foci with seasonal transmission in Mali and Senegal where treatment has been given for 15 to 17 years. As a result of this treatment, infection and transmission levels had fallen everywhere below postulated thresholds for elimination. Treatment was therefore stopped in each focus. Follow-up evaluations up to 5 years after the last treatment showed no evidence of recrudescence after stopping treatment but instead a consistent decline in infection and transmission levels, reaching zero in two sites. The study has established the proof-of-principle that onchocerciasis elimination with ivermectin treatment is feasible in at least some endemic foci in Africa. The results of the study have greatly contributed to the current evolution from onchocerciasis control to elimination in Africa. [ABSTRACT FROM AUTHOR]

Background: Several studies indicate that people of the Fulani ethnic group are less susceptible to malaria compared to those of other ethnic groups living sympatrically in Africa, including the Dogon ethnic group. Although the mechanisms of this protection remain unclear, the Fulani are known to have higher levels of Plasmodium falciparum-specific antibodies of all Ig classes as compared to the Dogon. However, the proportions of B cell subsets in the Fulani and Dogon that may account for differences in the levels of Ig have not been characterized. Methods: In this cross-sectional study, venous blood was collected from asymptomatic Fulani (n = 25) and Dogon (n = 25) adults in Mali during the malaria season, and from P. falciparum-naïve adults in the U.S. (n = 8). At the time of the blood collection, P. falciparum infection was detected by blood-smear in 16% of the Fulani and 36% of the Dogon volunteers. Thawed lymphocytes were analysed by flow cytometry to quantify B cell subsets, including immature and naïve B cells; plasma cells; and classical, activated, and atypical memory B cells (MBCs). Results: The overall distribution of B cell subsets was similar between Fulani and Dogon adults, although the percentage of activated MBCs was higher in the Fulani group (Fulani: 11.07% [95% CI: 9.317 -- 12.82]; Dogon: 8.31% [95% CI: 6.378 -- 10.23]; P = 0.016). The percentage of atypical MBCs was similar between Fulani and Dogon adults (Fulani: 28.3% [95% CI: 22.73 - 34.88]; Dogon: 29.3% [95% CI: 25.06 -- 33.55], but higher than U.S. adults (U.S.: 3.0% [95% CI: -0.21 - 6.164]; P<0.001). Plasmodium falciparum infection was associated with a higher percentage of plasma cells among Fulani (Fulani infected: 3.3% [95% CI: 1.788 -- 4.744]; Fulani uninfected: 1.71% [95% CI: 1.33 -- 2.08]; P = 0.011), but not Dogon adults. Conclusion: These data show that the malaria-resistant Fulani have a higher percentage of activated MBCs compared to the Dogon, and that P. falciparum infection is associated with a higher percentage of plasma cells in the Fulani compared to the Dogon, findings that may account for the higher levels of P. falciparum antibodies in the Fulani. [ABSTRACT FROM AUTHOR]

The article discusses the need of the needs of biomedical science training in Africa. To conduct the survey of the region, a total of 107 young scientists were recruited through existing international networks and interviewed via a web-based program, on the current status of biomedical research in their different institutions. Information on the obstacles for biomedical science research which include the lack of infrastructure and financial support from government is presented.

The Fulani ethnic group from West Africa is relatively better protected against Plasmodium falciparum malaria as compared to other sympatric ethnic groups, such as the Dogon. However, the mechanisms behind this lower susceptibility to malaria are largely unknown, particularly those concerning innate immunity. Antigen-presenting cells (APCs), and in particular dendritic cells (DCs) are important components of the innate and adaptive immune systems. Therefore, in this study we investigated whether APCs obtained from Fulani and Dogon children exhibited differences in terms of activation status and toll-like receptor (TLR) responses during malaria infection. Lower frequency and increased activation was observed in circulating plasmacytoid DCs and BDCA-3+ myeloid DCs of infected Fulani as compared to their uninfected counterparts. Conversely, a higher frequency and reduced activation was observed in the same DC subsets obtained from peripheral blood of P. falciparum-infected Dogon children as compared to their uninfected peers. Moreover, infected individuals of both ethnic groups exhibited higher percentages of both classical and inflammatory monocytes that were less activated as compared to their non-infected counterparts. In line with APC impairment during malaria infection, TLR4, TLR7 and TLR9 responses were strongly inhibited by P. falciparum infection in Dogon children, while no such TLR inhibition was observed in the Fulani children. Strikingly, the TLR-induced IFN-γ release was completely abolished in the Dogon undergoing infection while no difference was seen within infected and non-infected Fulani. Thus, P. falciparum infection is associated with altered activation status of important APC subsets and strongly inhibited TLR responses in peripheral blood of Dogon children. In contrast, P. falciparum induces DC activation and does not affect the innate response to specific TLR ligands in Fulani children. These findings suggest that DCs and TLR signalling may be of importance for the protective immunity against malaria observed in the Fulani. [ABSTRACT FROM AUTHOR]

Background. Annual mass treatment with albendazole and ivermectin is the mainstay of current strategies to interrupt transmission of Wuchereria bancrofti in Africa. More-effective microfilarial suppression could potentially reduce the time necessary to interrupt transmission, easing the economic burden of mass treatment programs in countries with limited resources. Methods. To determine the effect of increased dose and frequency of albendazole-ivermectin treatment on microfilarial clearance, 51 W. bancrofti microfilaremic residents of an area of W. bancrofti endemicity in Mali were randomized to receive 2 doses of annual, standard-dose albendazole-ivermectin therapy (400 mg and 150 mg/kg; ) np26 or 4 doses of twice-yearly, increased-dose albendazole-ivermectin therapy (800 mg and 400 mg/kg; np 25). Results. Although microfilarial levels decreased significantly after therapy in both groups, levels were significantly lower in the high-dose, twice-yearly group at 12, 18, and 24 months. Furthermore, there was complete clearance of detectable microfilariae at 12 months in the 19 patients in the twice-yearly therapy group with data available at 12 months, compared with 9 of 21 patients in the annual therapy group (P ! .001, by Fisher's exact test). This difference between the 2 groups was sustained at 18 and 24 months, with no detectable microfilariae in the patients receiving twice-yearly treatment. Worm nests detectable by ultrasonography and W. bancrofti circulating antigen levels, as measured by enzyme-linked immunosorbent assay, were decreased to the same degree in both groups at 24 months, compared with baseline. Conclusions. These findings suggest that increasing the dosage and frequency of albendazole-ivermectin treatment enhances suppression of microfilariae but that this effect may not be attributable to improved adulticidal activity. [ABSTRACT FROM AUTHOR]

Malaria during pregnancy is associated with maternal and fetal morbidity and mortality. In order to minimize the burden, sulfadoxine–pyrimethamine (SP) is widely used in Africa as an intermittent preventive treatment of malaria in pregnancy (IPTp). However, only limited data are available on the pharmacokinetics of sulfadoxine and pyrimethamine during pregnancy. We conducted a prospective, self-matched, multicenter study of 98 pregnant women in four African countries in order to determine the effects of pregnancy on SP pharmacokinetics. After adjusting for the effects of potential confounders, blood concentrations (associated with therapeutic efficacy) of pyrimethamine were higher (geometric mean ratio (GMR) 1.33; 95% confidence interval (CI) 1.18–1.51; P < 0.001) and those of sulfadoxine were lower (GMR 0.91; 95% CI 0.84–0.98; P = 0.013) on day 7 after SP administration during pregnancy than after the postpartum period. SP pharmacokinetic parameters differed significantly among the study sites. Given the inconsistency of changes in pharmacokinetic parameters between sulfadoxine and pyrimethamine as well as among the study sites, it is not possible to recommend any dose adjustment to prolong the therapeutic life span of the fixed dose combination of SP for IPTp on the basis of our study findings. [ABSTRACT FROM AUTHOR]

Background. Severe malaria (SM) due to Plasmodium falciparum causes millions of child deaths in sub-Saharan Africa. It comprises a variety of clinical disorders, including cerebral malaria (CM) and severe anemia (SA). In previous work, we have shown that interferon g and interleukin 12 protect against CM. Here, we investigated whether interleukin 4 (IL-4) aggravates the risk of severe disease. Methods. We prospectively recruited children with CM (n=240), SA (n=101), and uncomplicated malaria (UM) (n=42) in Bamako, Mali, and measured IL-4 production in plasma by enzyme-linked immunosorbent assay. We then assessed the influence of 11 polymorphisms on predisposition to SM by the family-based association test (FBAT). Results. IL-4 concentrations were higher in children with CM than in children with UM during malaria (P=.003). FBAT analyses showed that the most significant association was between the IL4 variable-number tandem repeat (VNTR) 1/2 genotype and SM (P < .001); an association was also observed for IL4 -33 C/T, rs2243267 G/C, rs2243268 C/A, and rs2243282 C/A (P < .05). Interestingly, we found that the plasma concentration of IL-4 was higher in subjects with the IL4 VNTR 1/2 or 1/1 genotype than with the IL4 VNTR 2/2 genotype (P=.003). Conclusions. These results support the view that IL-4 may be a risk factor for SM. IL-4 may aggravate the disease by interfering with type 1 T helper cell differentiation or by promoting local inflammation at sites of parasite sequestration. [ABSTRACT FROM AUTHOR]

Background: The use of artemisinin derivative-based combination therapy (ACT) such as artesunate plus amodiaquine is currently recommended for the treatment of uncomplicated Plasmodium falciparum malaria. Fixed-dose combinations are more adapted to patients than regimens involving multiple tablets and improve treatment compliance. A fixed-dose combination of artesunate + amodiaquine (ASAQ) was recently developed. To assess the efficacy and safety of this new combination and to define its optimum dosage regimen (once or twice daily) in the treatment of uncomplicated P. falciparum malaria, a multicentre clinical study was conducted. Methods: A multicentre, randomized, controlled, investigator-blinded, parallel-group study was conducted in five African centers in Cameroon, Madagascar, Mali and Senegal from March to December 2006. Efficacy and safety of ASAQ were assessed compared to those of artemether + lumefantrine (AL). The WHO protocol with a 28-day follow-up for assessing the drug therapeutic efficacy was used. Patients suffering from uncomplicated P. falciparum malaria were randomized to receive ASAQ orally once daily (ASAQ1), ASAQ twice daily (ASAQ2) or AL twice daily (AL) for three days. The primary outcome was PCR-corrected parasitological cure rate and clinical response. Results: Of 941 patients initially randomized and stratified into two age groups (<5 years, and ⩾5 years), 936 (99.5%) were retained for the intent to treat (ITT) analysis, and 859 (91.3%) patients for the per protocol (PP) analysis. Among ITT population, up to D28, PCR-corrected adequate parasitological and clinical response rates were 95.2% in the ASAQ1 group, 94.9% in the ASAQ2 group and 95.5% in the AL group. Moreover, the cure rate evaluated among PP population was =98.5% in both ASAQ therapeutic arms. Therapeutic response rates did not display any significant differences between age groups or between one geographical site and another. Altogether, this demonstrates the non-inferiority of ASAQ1 regimen compared to both ASAQ2 and AL regimens. During follow-up mild and moderate adverse events including gastrointestinal and/or nervous disorders were reported in 29.3% of patients, with no difference between groups in the nature, frequency or intensity of adverse events. Conclusion: The non-inferiority of ASAQ compared with AL was demonstrated. The fixed-dose combination artesunate + amodiaquine (ASAQ) is safe and efficacious even in young children under 5 years of age. Whilst administration on a twice-a-day basis does not improve the efficacy of ASAQ significantly, a once-a-day intake of this new combination clearly appears as an effective and safe therapy in the treatment of uncomplicated P. falciparum malaria both in adults and children. Implications of such findings are of primary importance in terms of public health especially in African countries. As most national policies plan to strengthen malaria control to reach the elimination of this disease, anti-malarial drugs such as the artesunate + amodiaquine fixed-dose ACT will play a pivotal role in this process. [ABSTRACT FROM AUTHOR]

Background: The efficacy of artemisinin-based combination therapy has already been demonstrated in a number of studies all over the world, and some of them can be regarded as comparably effective. Ease of administration of anti-malarial treatments with shorter courses and fewer tablets may be key determinant of compliance. Methods: Patients with uncomplicated falciparum malaria and over six months of age were recruited in Cameroon, Mali, Rwanda and Sudan. 1,384 patients were randomly assigned to receive artesunate-sulphamethoxypyrazine-pyrimethamine (ASSMP) three-day (once daily for 3 days) regimen (N = 476) or AS-SMP 24-hour (0 h, 12 h, 24 h) regimen (N = 458) or artemetherlumefantrine (AL), the regular 6 doses regimen (N = 450). The primary objective was to demonstrate non-inferiority (using a margin of -6%) of AS-SMP 24 hours or AS-SMP three days versus AL on the PCR-corrected 28-day cure rate. Results: The PCR corrected 28-day cure rate on the intention to treat (ITT) analysis population were: 96.0%(457/476) in the AS-SMP three-day group, 93.7%(429/458) in the AS-SMP 24-hour group and 92.0%(414/450) in the AL group. Likewise, the cure rates on the PP analysis population were high: 99.3%(432/437) in the AS-SMP three-day group, 99.5%(416/419) in the AS-SMP 24-hour group and 99.7(391/394)% in the AL group. Most common drug-related adverse events were gastrointestinal symptoms (such as vomiting and diarrhea) which were slightly higher in the AS-SMP 24-hour group. Conclusion: AS-SMP three days or AS-SMP 24 hours are safe, are as efficacious as AL, and are well tolerated. [ABSTRACT FROM AUTHOR]

In July of 2006, the National Institute of Mental Health (NIMH) Center for Mental Health Research on AIDS (CMHRA) sponsored the second conference on the Assessment of NeuroAIDS in Africa, which was held in Arusha, Tanzania. The conference mission was to address the regional variations in epidemiology of HIV-related neurological disorders as well as the assessment and diagnosis of these disorders. Participants discussed and presented data regarding the relevance and translation of neuroAIDS assessment measures developed in resource intensive settings and the challenges of neuro-assessment in Africa, including the applicability of current tools, higher prevalence of confounding diseases, and the complexity of diverse cultural settings. The conference presentations summarized here highlight the need for further research on neuroAIDS in Africa and methods for assessing HIV-related neurological disorders. [ABSTRACT FROM AUTHOR]

Background. The objective was to evaluate the safety, reactogenicity and immunogenicity of the AMA-1-based blood-stage malaria vaccine FMP2.1/AS02A in adults exposed to seasonal malaria. Methodology/Principal Findings. A phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02A is a recombinant protein (FMP2.1) based on apical membrane antigen-1 (AMA-1) from the 3D7 clone of P. falciparum, adjuvanted with AS02A. The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert). Sixty healthy, malaria-experienced adults aged 18-55 y were recruited into 2 cohorts and randomized to receive either a half dose or full dose of the malaria vaccine (FMP2.1 25 μg/AS02A 0.25 mL or FMP2.1 50 μg/AS02A 0.5 mL) or rabies vaccine given in 3 doses at 0, 1 and 2 mo, and were followed for 1 y. Solicited symptoms were assessed for 7 d and unsolicited symptoms for 30 d after each vaccination. Serious adverse events were assessed throughout the study. Titers of anti-AMA-1 antibodies were measured by ELISA and P. falciparum growth inhibition assays were performed on sera collected at pre- and post-vaccination time points. Transient local pain and swelling were common and more frequent in both malaria vaccine dosage groups than in the comparator group. Anti-AMA-1 antibodies increased significantly in both malaria vaccine groups, peaking at nearly 5-fold and more than 6-fold higher than baseline in the half-dose and full-dose groups, respectively. Conclusion/Significance. The FMP2.1/AS02A vaccine had a good safety profile, was well-tolerated, and was highly immunogenic in malaria-exposed adults. This malaria vaccine is being evaluated in Phase 1 and 2 trials in children at this site. [ABSTRACT FROM AUTHOR]

Background: The burden of Plasmodium falciparum malaria has worsened because of the emergence of chloroquine resistance. Antimalarial drug use and drug pressure are critical factors contributing to the selection and spread of resistance. The present study explores the geographical, socio-economic and behavioural factors associated with the use of antimalarial drugs in Africa. Methods: The presence of chloroquine (CQ), pyrimethamine (PYR) and other antimalarial drugs has been evaluated by immuno-capture and high-performance liquid chromatography in the urine samples of 3,052 children (2-9 y), randomly drawn in 2003 from the general populations at 30 sites in Senegal (10), Burkina-Faso (10) and Cameroon (10). Questionnaires have been administered to the parents of sampled children and to a random sample of households in each site. The presence of CQ in urine was analysed as dependent variable according to individual and site characteristics using a random -- effect logistic regression model to take into account the interdependency of observations made within the same site. Results: According to the sites, the prevalence rates of CQ and PYR ranged from 9% to 91% and from 0% to 21%, respectively. In multivariate analysis, the presence of CQ in urine was significantly associated with a history of fever during the three days preceding urine sampling (OR = 1.22, p = 0.043), socio-economic level of the population of the sites (OR = 2.74, p = 0.029), age (2-5 y = reference level; 6-9 y OR = 0.76, p = 0.002), prevalence of anti-circumsporozoite protein (CSP) antibodies (low prevalence: reference level; intermediate level OR = 2.47, p = 0.023), proportion of inhabitants who lived in another site one year before (OR = 2.53, p = 0.003), and duration to reach the nearest tarmacked road (duration less than one hour = reference level, duration equal to or more than one hour OR = 0.49, p = 0.019). Conclusion: Antimalarial drug pressure varied considerably from one site to another. It was significantly higher in areas with intermediate malaria transmission level and in the most accessible sites. Thus, P. falciparum strains arriving in cross-road sites or in areas with intermediate malaria transmission are exposed to higher drug pressure, which could favour the selection and the spread of drug resistance. [ABSTRACT FROM AUTHOR]

Background Malaria vaccines based on the 19-kDa region of merozoite surface protein 1 (MSP-119) derived from the 3D7 strain of Plasmodium falciparum are being tested in clinical trials in Africa. Knowledge of the distribution and natural dynamics of vaccine antigen polymorphisms in populations in which malaria vaccines will be tested will guide vaccine design and permit distinction between natural fluctuations in genetic diversity and vaccine-induced selection. Methods and Findings Using pyrosequencing, six single-nucleotide polymorphisms in the nucleotide sequence encoding MSP-1M19 were genotyped from 1,363 malaria infections experienced by 100 children who participated in a prospective cohort study in Mali from 1999 to 2001. The frequencies of 14 MSP-119 haplotypes were compared over the course of the malaria transmission season for all three years, in three age groups, and in consecutive infections within individuals. While the frequency of individual MSP-119 haplotypes fluctuated, haplotypes corresponding to FVO and FUP strains of P. falciparum (MSP-119 haplotypes QKSNGL and EKSNGL, respectively) were most prevalent during three consecutive years and in all age groups with overall prevalences of 46% (95% confidence interval [CI] 44%-49%) and 36% (95% CI 34%-39%), respectively. The 3D7 haplotype had a lower overall prevalence of 16% (95% CI 14%-18%). Multiplicity of infection based on MSP-119 was higher at the beginning of the transmission season and in the oldest individuals (aged ≥11 y). Three MSP-119 haplotypes had a reduced frequency in symptomatic infections compared to asymptomatic infections. Analyses of the dynamics of MSP-119 polymorphisms in consecutive infections implicate three polymorphisms (at positions 1691, 1700, and 1701) as being particularly important in determining allele specificity of anti-MSP-119 immunity. Conclusions Parasites with MSP-119 haplotypes different from that of the leading vaccine strain were consistently the most prevalent at a vaccine trial site. If immunity elicited by an MSP-1-based vaccine is allele-specific, a vaccine based on either the FVO or FUP strain might have better initial efficacy at this site. This study, to our knowledge the largest of its kind to date, provides molecular information needed to interpret population responses to MSP-1-based vaccines and suggests that certain MSP-119 polymorphisms may be relevant to cross-protective immunity. [ABSTRACT FROM AUTHOR]

Antibodies to human immunodeficiency virus (HIV) of the IgA, IgG, and IgM isotypes and high levels of the HIV suppressive b-chemokine RANTES (regulated on activation, normally T cell expressed and secreted) were found in the cervicovaginal secretions (CVSs) of 7.5% of 342 multiply and repeatedly exposed African HIV-seronegative female sex workers. The anti-bodies are part of a local compartmentalized secretory immune response to HIV, since they are present in vaginal fluids that are free of contaminating semen. Cervicovaginal antibodies showed a reproducible pattern of reactivity restricted to gp160 and p24. Locally produced anti-env antibodies exhibit reactivity toward the neutralizing ELDKWA epitope of gp41. Study results show that antibodies purified from CVSs block the transcytosis of cell-associated HIV through a tight epithelial monolayer in vitro. These findings suggest that genital resistance to HIV may involve HIV-specific cervicovaginal antibody responses in a minority of highly exposed HIV-seronegative women in association with other protecting factors, such as local production of HIV-suppressive chemokines. [ABSTRACT FROM AUTHOR]

The distribution of Aedes albopictus in Africa has thus far been known to be restricted to coastal Sub-Saharan countries. This report describes the first record of the tiger mosquito in habitats located in Mali, at a significant distance from the coastal areas of the continent. Aedes albopictus was observed over several years in increasing frequency in Mopti in Central Mali and later in the capital city Bamako, both adjacent to the Niger River. These findings suggest further dissemination of Ae. albopictus could be facilitated by river transport of goods and commodities which harbor larvae and eggs of this species. If correct, the distribution of Ae. albopictus is expected to extend to areas located upstream of the Niger River and its tributaries. [ABSTRACT FROM AUTHOR]

The hyperhemolysis paradigm that describes overlapping "hyperhemolytic-endothelial dysfunction" and "high hemoglobin-hyperviscous" subphenotypes of sickle cell disease (SCD) patients is based on North American studies. We performed a transversal study nested in the CADRE cohort to analyze the association between steady-state hemolysis and vascular complications of SCD among sub-Saharan African patients. In Mali, Cameroon, and Ivory Coast, 2407 SCD patients (1751 SS or sickle β-zero-thalassemia [Sβ0], 495 SC, and 161 sickle β+-thalassemia [Sβ+]), aged 3 years old and over, were included at steady state. Relative hemolytic intensity was estimated from a composite index derived from principal component analysis, which included bilirubin levels or clinical icterus, and lactate dehydrogenase levels. We assessed vascular complications (elevated tricuspid regurgitant jet velocity [TRV], microalbuminuria, leg ulcers, priapism, stroke, and osteonecrosis) by clinical examination, laboratory tests, and echocardiography. After adjustment for age, sex, country, and SCD phenotype, a low hemoglobin level was significantly associated with TRV and microalbuminuria in the whole population and with leg ulcers in SS-Sβ0 adults. A high hemolysis index was associated with microalbuminuria in the whole population and with elevated TRV, microalbuminuria, and leg ulcers in SS-Sβ0 adults, but these associations were no longer significant after adjustment for hemoglobin level. In conclusion, severe anemia at steady state in SCD patients living in West and Central Africa is associated with elevated TRV, microalbuminuria, and leg ulcers, but these vascular complications are not independently associated with indirect markers of increased hemolysis. Other mechanisms leading to anemia, including malnutrition and infectious diseases, may also play a role in the development of SCD vasculopathy. [ABSTRACT FROM AUTHOR]

Background: Strategies to prevent postnatal mother-to-child transmission of HIV-1 in Africa, including infant prophylaxis, have never been assessed past 6 months of breastfeeding, despite breastfeeding being recommended up to 12 months after birth. We aimed to compare the efficacy and safety of infant prophylaxis with the two drug regimens (lamivudine or lopinavir-ritonavir) to prevent postnatal HIV-1 transmission up to 50 weeks of breastfeeding.Methods: We did a randomised controlled trial in four sites in Burkina Faso, South Africa, Uganda, and Zambia in children born to HIV-1-infected mothers not eligible for antiretroviral therapy (CD4 count >350 cells per μL). An independent researcher electronically generated a randomisation schedule; we then used sequentially numbered envelopes to randomly assign (1:1) HIV-1-uninfected breastfed infants aged 7 days to either lopinavir-ritonavir or lamivudine (paediatric liquid formulations, twice a day) up to 1 week after complete cessation of breastfeeding or at the final visit at week 50. We stratified the randomisation by country and used permuted blocks of four and six. We used a study label on drug bottles to mask participants, study physicians, and assessors to the treatment allocation. The primary outcome was infant HIV-1 infection between age 7 days and 50 weeks, diagnosed every 3 months with HIV-1 DNA PCR, in the modified intention-to-treat population (all who attended at least one follow-up visit). This trial is registered with ClinicalTrials.gov, number NCT00640263.Findings: Between Nov 16, 2009, and May 7, 2012, we enrolled and randomised 1273 infants and analysed 1236; 615 assigned to lopinavir-ritonavir or 621 assigned to lamivudine. 17 HIV-1 infections were diagnosed in the study period (eight in the lopinavir-ritonavir group and nine in the lamivudine group), resulting in cumulative HIV-1 infection of 1.4% (95% CI 0.4-2.5) and 1.5% (0.7-2.5), respectively. Infection rates did not differ between the two drug regimens (hazard ratio [HR] of lopinavir-ritonavir versus lamivudine of 0.90, 95% CI 0.35-2.34; p=0.83). Clinical and biological severe adverse events did not differ between groups; 251 (51%) infants had a grade 3-4 event in the lopinavir-ritonavir group compared with 246 (50%) in the lamivudine group.Interpretation: Infant HIV-1 prophylaxis with lopinavir-ritonavir was not superior to lamivudine and both drugs led to very low rates of HIV-1 postnatal transmission for up to 50 weeks of breastfeeding. Infant pre-exposure prophylaxis should be extended until the end of HIV-1 exposure and mothers should be informed about the persistent risk of transmission throughout breastfeeding.Funding: INSERM/National Agency for Research on AIDS and Viral Hepatitis (including funds from the Total Foundation), European Developing Countries Clinical Trials Partnership, Research Council of Norway. [ABSTRACT FROM AUTHOR]

Highlights: [•] Regular crop yield benefits from conservation agriculture (CA) take time to occur. [•] CA has a potential to mitigate negative effects from climate change. [•] The impact of CA on farm income is not evident, and depends on the type of farm. [•] Strong trade-offs between CA and livestock exist at farm and village scale. [•] Poor markets are a major bottleneck for adoption of CA. [ABSTRACT FROM AUTHOR]

The article presents a study on the importance of adapting to climate change in the semi-arid tropics (SAT) of Africa and Asia which was conducted by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) from 2008-2015. The study intends to help farmers and stakeholders adapt to the future climate change. The adaptability to climate change helps farmers produce higher crop yields, soil and water management practices.