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1.
Sci Adv ; 10(14): eadl0335, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38569032

RESUMEN

The rapid growth of clean energy technologies is driving a rising demand for critical minerals. In 2022 at the 15th Conference of the Parties to the Convention on Biological Diversity (COP15), seven major economies formed an alliance to enhance the sustainability of mining these essential decarbonization minerals. However, there is a scarcity of studies assessing the threat of mining to global biodiversity. By integrating a global mining dataset with great ape density distribution, we estimated the number of African great apes that spatially coincided with industrial mining projects. We show that up to one-third of Africa's great ape population faces mining-related risks. In West Africa in particular, numerous mining areas overlap with fragmented ape habitats, often in high-density ape regions. For 97% of mining areas, no ape survey data are available, underscoring the importance of increased accessibility to environmental data within the mining sector to facilitate research into the complex interactions between mining, climate, biodiversity, and sustainability.


Asunto(s)
Hominidae , Animales , Ecosistema , Biodiversidad , Minerales , África Occidental
2.
Nature ; 628(8008): 563-568, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38600379

RESUMEN

More than a quarter of the world's tropical forests are exploited for timber1. Logging impacts biodiversity in these ecosystems, primarily through the creation of forest roads that facilitate hunting for wildlife over extensive areas. Forest management certification schemes such as the Forest Stewardship Council (FSC) are expected to mitigate impacts on biodiversity, but so far very little is known about the effectiveness of FSC certification because of research design challenges, predominantly limited sample sizes2,3. Here we provide this evidence by using 1.3 million camera-trap photos of 55 mammal species in 14 logging concessions in western equatorial Africa. We observed higher mammal encounter rates in FSC-certified than in non-FSC logging concessions. The effect was most pronounced for species weighing more than 10 kg and for species of high conservation priority such as the critically endangered forest elephant and western lowland gorilla. Across the whole mammal community, non-FSC concessions contained proportionally more rodents and other small species than did FSC-certified concessions. The first priority for species protection should be to maintain unlogged forests with effective law enforcement, but for logged forests our findings provide convincing data that FSC-certified forest management is less damaging to the mammal community than is non-FSC forest management. This study provides strong evidence that FSC-certified forest management or equivalently stringent requirements and controlling mechanisms should become the norm for timber extraction to avoid half-empty forests dominated by rodents and other small species.


Asunto(s)
Certificación , Agricultura Forestal , Bosques , Mamíferos , Animales , África Occidental , Biodiversidad , Peso Corporal , Conservación de los Recursos Naturales/legislación & jurisprudencia , Conservación de los Recursos Naturales/métodos , Elefantes , Agricultura Forestal/legislación & jurisprudencia , Agricultura Forestal/métodos , Agricultura Forestal/normas , Gorilla gorilla , Mamíferos/anatomía & histología , Mamíferos/clasificación , Mamíferos/fisiología , Fotograbar , Roedores , Masculino , Femenino
3.
Emerg Microbes Infect ; 13(1): 2337666, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38572513

RESUMEN

Monkeypox virus (MPXV) infection confirmation needs reliable polymerase chain reaction (PCR) assays; in addition, viral clade attribution is a key factor in containment measures, considering a more severe syndrome in clade I and the possibility of simultaneous circulation. This study evaluates the performance of all-in-one STANDARD M10 MPX/OPX (SD BIOSENSOR, South Korea - M10). Frozen samples from 205 subjects were selected and stratified according to routine test results (RealStar® Orthopoxvirus PCR Kit 1.0, Altona DIAGNOTICS, Germany - RS; RS-1): in detail, 100 negative skin lesions (SL) and 200 positive samples at the variable stage of infection were analysed. Positive samples were retested with RS (RS-2). Positive and Negative Percent Agreements (PPA, NPA) were calculated. The median (IQR) Ct values of RS and M10 (OPXV target) assays were highly similar. The PPA of M10 compared to RS-1 was 89.5% considering system interpretation, and 96.0% when the operator classified results as positive if any target was detected; NPA was 100%. Comparing the RS-2 run and M10, an overall concordance of 95.3% between assays was found; however, considering operator interpretation, M10 returned more positive results than RS-2. The occurrence of False-Negative results was likely associated with the influence of thawing on low viral concentration; no False-Positive tests were observed. All samples collected at the time of Mpox diagnosis were positive and M10 correctly attributed the clade (West-Africa/II). The M10 MPX/OPX assay demonstrated high reliability in confirming MPXV infection and clade attribution.


Asunto(s)
Virus de la Viruela de los Monos , Viruela del Mono , Humanos , Virus de la Viruela de los Monos/genética , Viruela del Mono/diagnóstico , Reproducibilidad de los Resultados , ADN Viral/genética , África Occidental
4.
Proc Natl Acad Sci U S A ; 121(15): e2320687121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38557179

RESUMEN

The Mediterranean Sea is a marine biodiversity hotspot already affected by climate-driven biodiversity collapses. Its highly endemic fauna is at further risk if global warming triggers an invasion of tropical Atlantic species. Here, we combine modern species occurrences with a unique paleorecord from the Last Interglacial (135 to 116 ka), a conservative analog of future climate, to model the future distribution of an exemplary subset of tropical West African mollusks, currently separated from the Mediterranean by cold upwelling off north-west Africa. We show that, already under an intermediate climate scenario (RCP 4.5) by 2050, climatic connectivity along north-west Africa may allow tropical species to colonize a by then largely environmentally suitable Mediterranean. The worst-case scenario RCP 8.5 leads to a fully tropicalized Mediterranean by 2100. The tropical Atlantic invasion will add to the ongoing Indo-Pacific invasion through the Suez Canal, irreversibly transforming the entire Mediterranean into a novel ecosystem unprecedented in human history.


Asunto(s)
Biodiversidad , Ecosistema , Humanos , Mar Mediterráneo , Calentamiento Global , África Occidental
5.
Emerg Microbes Infect ; 13(1): 2341141, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38597241

RESUMEN

The Natal multimammate mouse (Mastomys natalensis) is the host of Lassa mammarenavirus, causing Lassa haemorrhagic fever in West Africa. As there is currently no operational vaccine and therapeutic drugs are limited, we explored rodent control as an alternative to prevent Lassa virus spillover in Upper Guinea, where the disease is highly endemic in rural areas. In a seven-year experiment, we distributed rodenticides for 10-30 days once a year and, in the last year, added intensive snap trapping for three months in all the houses of one village. We also captured rodents both before and after the intervention period to assess their effectiveness by examining alterations in trapping success and infection rates (Lassa virus RNA and IgG antibodies). We found that both interventions reduced the rodent population by 74-92% but swiftly rebounded to pre-treatment levels, even already six months after the last snap-trapping control. Furthermore, while we observed that chemical control modestly decreased Lassa virus infection rates annually (a reduction of 5% in seroprevalence per year), the intensive trapping unexpectedly led to a significantly higher infection rate (from a seroprevalence of 28% before to 67% after snap trapping control). After seven years, we conclude that annual chemical control, alone or with intensive trapping, is ineffective and sometimes counterproductive in preventing Lassa virus spillover in rural villages. These unexpected findings may result from density-dependent breeding compensation following culling and the survival of a small percentage of chronically infected rodents that may spread the virus to a new susceptible generation of mice.


Asunto(s)
Fiebre de Lassa , Virus Lassa , Ratones , Animales , Virus Lassa/genética , Guinea/epidemiología , Control de Roedores , Estudios Seroepidemiológicos , Reservorios de Enfermedades , Fiebre de Lassa/epidemiología , Fiebre de Lassa/prevención & control , Murinae , África Occidental/epidemiología
6.
PLoS One ; 19(3): e0299082, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38446806

RESUMEN

SARS-CoV-2 has claimed several million lives since its emergence in late 2019. The ongoing evolution of the virus has resulted in the periodic emergence of new viral variants with distinct fitness advantages, including enhanced transmission and immune escape. While several SARS-CoV-2 variants of concern trace their origins back to the African continent-including Beta, Eta, and Omicron-most countries in Africa remain under-sampled in global genomic surveillance efforts. In an effort to begin filling these knowledge gaps, we conducted retrospective viral genomic surveillance in Guinea from October 2020 to August 2021. We found that SARS-CoV-2 clades 20A, 20B, and 20C dominated throughout 2020 until the coincident emergence of the Alpha and Eta variants of concern in January 2021. The Alpha variant remained dominant throughout early 2021 until the arrival of the Delta variant in July. Surprisingly, despite the small sample size of our study, we also found the persistence of the early SARS-CoV-2 clade 19B as late as April 2021. Together, these data help fill in our understanding of the SARS-CoV-2 population dynamics in West Africa early in the COVID-19 pandemic.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Guinea/epidemiología , SARS-CoV-2/genética , Pandemias , Estudios Retrospectivos , COVID-19/epidemiología , África Occidental/epidemiología , Genómica
7.
PLoS One ; 19(3): e0294346, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38547134

RESUMEN

The understanding of cultural dynamics at work at the end of the Final Pleistocene in West Africa suffers from a significant lack of excavated and dated sites, particularly in the Sahelian and Sudanian ecozones. While the Later Stone Age shows varied behavioral developments in different parts of the continent, the chrono-cultural framework of this period remains largely unknown in West Africa. We report on archaeological, geomorphological, and chronological research on two Final Pleistocene Later Stone Age sites in the Falémé Valley, eastern Senegal. Optically stimulated luminescence ages place the site of Toumboura I-2017 between 17 ± 1 and 16 ± 1 ka and the Ravin de Sansandé site between 13 ± 1 ka and 12 ± 1.1 ka. The excavated lithics show typical Later Stone Age industries, characterized by chaînes opératoires of core reduction mainly producing flakes and bladelets as well as blades and laminar flakes. Segments dominate the toolkits but a few backed bladelets and end-scrapers on flake blanks were recognized. Local raw materials were used, with a preference for chert and quartz, as well as greywacke. These Later Stone Age lithic assemblages are the oldest known in Senegal so far and add to the small number of sites known in West Africa for this period, which are mainly located farther south, in sub-tropical ecozones. The Later Stone Age sites of the Falémé Valley are contemporaneous with typical Middle Stone Age technologies in Senegal dated to at least the Pleistocene/Holocene transition. Our results thus provide new archaeological evidence highlighting the complex cultural processes at work during the Final Pleistocene in West Africa.


Asunto(s)
Fósiles , Hominidae , Animales , Senegal , Ambiente , África Occidental , Arqueología/métodos
8.
Demography ; 61(2): 493-511, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38526178

RESUMEN

In the wake of the COVID-19 pandemic, the International Organization for Migration has postulated that international migrant stocks fell short of their pre-pandemic projections by nearly 2 million as a result of travel restrictions. However, this decline is not testable with migration data from traditional sources. Key migration stakeholders have called for using data from alternative sources, including social media, to fill these gaps. Building on previous work using social media data to analyze migration responses to external shocks, we test the hypothesis that COVID-related travel restrictions reduced migrant stock relative to expected migration without such restrictions using estimates of migrants drawn from Facebook's advertising platform and dynamic panel models. We focus on four key origin countries in North and West Africa (Côte d'Ivoire, Algeria, Morocco, and Senegal) and on their 23 key destination countries. Between February and June 2020, we estimate that a destination country implementing a month-long total entry ban on arrivals from Côte d'Ivoire, Algeria, Morocco, or Senegal might have expected a 3.39% reduction in migrant stock from the restricted country compared with the counterfactual in which no travel restrictions were implemented. However, when broader societal disruptions of the pandemic are accounted for, we estimate that countries implementing travel restrictions might paradoxically have expected an increase in migrant stock. In this context, travel restrictions do not appear to have effectively curbed migration and could have resulted in outcomes opposite their intended effects.


Asunto(s)
COVID-19 , Medios de Comunicación Sociales , Humanos , Pandemias , Países en Desarrollo , COVID-19/epidemiología , África Occidental
9.
Sci Total Environ ; 926: 171850, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38521255

RESUMEN

Agriculture is expanding rapidly across the tropics. While cultivation can boost socioeconomic conditions and food security, it also threatens native ecosystems. Oil palm (Elaeis guineensis), which is grown pantropically, is the most productive vegetable oil crop worldwide. The impacts of oil palm cultivation have been studied extensively in Southeast Asia and - to a lesser extent - in Latin America but, in comparison, very little is known about its impacts in Africa: oil palm's native range, and where cultivation is expanding rapidly. In this paper, we introduce a large-scale research programme - the Sustainable Oil Palm in West Africa (SOPWA) Project - that is evaluating the relative ecological impacts of oil palm cultivation under traditional (i.e., by local people) and industrial (i.e., by a large-scale corporation) management in Liberia. Our paper is twofold in focus. First, we use systematic mapping to appraise the literature on oil palm research in an African context, assessing the geographic and disciplinary focus of existing research. We found 757 publications occurring in 36 African countries. Studies tended to focus on the impacts of palm oil consumption on human health and wellbeing. We found no research that has evaluated the whole-ecosystem (i.e., multiple taxa and ecosystem functions) impacts of oil palm cultivation in Africa, a knowledge gap which the SOPWA Project directly addresses. Second, we describe the SOPWA Project's study design and-using canopy cover, ground vegetation cover, and soil temperature data as a case study-demonstrate its utility for assessing differences between areas of rainforest and oil palm agriculture. We outline the socioecological data collected by the SOPWA Project to date and describe the potential for future research, to encourage new collaborations and additional similar projects of its kind in West Africa. Increased research in Africa is needed urgently to understand the combined ecological and sociocultural impacts of oil palm and other agriculture in this unique region. This will help to ensure long-term sustainability of the oil palm industry-and, indeed, all tropical agricultural activity-in Africa.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Humanos , Aceites de Plantas , Agricultura , África Occidental
10.
Malar J ; 23(1): 78, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491345

RESUMEN

BACKGROUND: Vegetation health (VH) is a powerful characteristic for forecasting malaria incidence in regions where the disease is prevalent. This study aims to determine how vegetation health affects the prevalence of malaria and create seasonal weather forecasts using NOAA/AVHRR environmental satellite data that can be substituted for malaria epidemic forecasts. METHODS: Weekly advanced very high-resolution radiometer (AVHRR) data were retrieved from the NOAA satellite website from 2009 to 2021. The monthly number of malaria cases was collected from the Ministry of Health of Benin from 2009 to 2021 and matched with AVHRR data. Pearson correlation was calculated to investigate the impact of vegetation health on malaria transmission. Ordinary least squares (OLS), support vector machine (SVM) and principal component regression (PCR) were applied to forecast the monthly number of cases of malaria in Northern Benin. A random sample of proposed models was used to assess accuracy and bias. RESULTS: Estimates place the annual percentage rise in malaria cases at 9.07% over 2009-2021 period. Moisture (VCI) for weeks 19-21 predicts 75% of the number of malaria cases in the month of the start of high mosquito activities. Soil temperature (TCI) and vegetation health index (VHI) predicted one month earlier than the start of mosquito activities through transmission, 78% of monthly malaria incidence. CONCLUSIONS: SVM model D is more effective than OLS model A in the prediction of malaria incidence in Northern Benin. These models are a very useful tool for stakeholders looking to lessen the impact of malaria in Benin.


Asunto(s)
Malaria , Mosquitos Vectores , Animales , Humanos , Benin/epidemiología , Malaria/epidemiología , Tiempo (Meteorología) , África Occidental/epidemiología
11.
JAMA ; 331(9): 778-791, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38441582

RESUMEN

Importance: Systemic amyloidosis from transthyretin (ATTR) protein is the most common type of amyloidosis that causes cardiomyopathy. Observations: Transthyretin (TTR) protein transports thyroxine (thyroid hormone) and retinol (vitamin A) and is synthesized predominantly by the liver. When the TTR protein misfolds, it can form amyloid fibrils that deposit in the heart causing heart failure, heart conduction block, or arrhythmia such as atrial fibrillation. The biological processes by which amyloid fibrils form are incompletely understood but are associated with aging and, in some patients, affected by inherited variants in the TTR genetic sequence. ATTR amyloidosis results from misfolded TTR protein deposition. ATTR can occur in association with normal TTR genetic sequence (wild-type ATTR) or with abnormal TTR genetic sequence (variant ATTR). Wild-type ATTR primarily manifests as cardiomyopathy while ATTR due to a genetic variant manifests as cardiomyopathy and/or polyneuropathy. Approximately 50 000 to 150 000 people in the US have heart failure due to ATTR amyloidosis. Without treatment, heart failure due to ATTR amyloidosis is associated with a median survival of approximately 5 years. More than 130 different inherited genetic variants in TTR exist. The most common genetic variant is Val122Ile (pV142I), an allele with an origin in West African countries, that is present in 3.4% of African American individuals in the US or approximately 1.5 million persons. The diagnosis can be made using serum free light chain assay and immunofixation electrophoresis to exclude light chain amyloidosis combined with cardiac nuclear scintigraphy to detect radiotracer uptake in a pattern consistent with amyloidosis. Loop diuretics, such as furosemide, torsemide, and bumetanide, are the primary treatment for fluid overload and symptomatic relief of patients with ATTR heart failure. An ATTR-directed therapy that inhibited misfolding of the TTR protein (tafamidis, a protein stabilizer), compared with placebo, reduced mortality from 42.9% to 29.5%, reduced hospitalizations from 0.7/year to 0.48/year, and was most effective when administered early in disease course. Conclusions and Relevance: ATTR amyloidosis causes cardiomyopathy in up to approximately 150 000 people in the US and tafamidis is the only currently approved therapy. Tafamidis slowed progression of ATTR amyloidosis and improved survival and prevented hospitalization, compared with placebo, in people with ATTR-associated cardiomyopathy.


Asunto(s)
Amiloidosis , Cardiomiopatías , Insuficiencia Cardíaca , Prealbúmina , Humanos , Amiloidosis/complicaciones , Amiloidosis/epidemiología , Amiloidosis/genética , Amiloidosis/metabolismo , Cardiomiopatías/etiología , Cardiomiopatías/genética , Cardiomiopatías/metabolismo , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/metabolismo , Amiloidosis de Cadenas Ligeras de las Inmunoglobulinas , Prealbúmina/genética , Prealbúmina/metabolismo , Negro o Afroamericano/etnología , Negro o Afroamericano/genética , Negro o Afroamericano/estadística & datos numéricos , Estados Unidos/epidemiología , África Occidental , Pliegue de Proteína
12.
BMC Health Serv Res ; 24(1): 282, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443896

RESUMEN

BACKGROUND: Infertility is a major health issue worldwide, yet very few examples of interventions addressing infertility in the Global South have been documented to date. In The Gambia, West Africa, infertility is recognised as a burden and the health authorities have included it in several health policies and the new National Reproductive Health Strategy however, a detailed operationalisation plan for fertility care has not yet been established. Here, we aim to understand and document the factors that influence the implementation of fertility care in The Gambia. METHODS: We conducted 46 semi-structured interviews with policymakers, implementers, and health practitioners in both the public and private sectors from July to November 2021. The interviews were transcribed, anonymised and analysed with NVivo Pro version 1.6.1. The analysis was initially inductive, with themes arising from the coding categorised according to the WHO health systems building blocks framework. RESULTS: This study identified several barriers to a successful implementation of fertility care in The Gambia, including (i) a lack of routinely collected infertility data; (ii) an absence of financial protection mechanisms for patients, and/or a specific budget for infertility; (iii) limited cooperation between the public and private sectors in the provision of fertility care; and (iv) gaps in fertility care training among health practitioners. Conversely, enablers included: (i) strong national infertility leadership; and (ii) the integration of infertility care within public reproductive health services. CONCLUSION: The Gambian health system is not yet in the position to support a comprehensive fertility care package in its public health facilities. Several aspects of the implementation of fertility care must be considered in operationalising the health strategy including the systematic collection of infertility data, fertility awareness, and the provision of specialised fertility care training. Furthermore, a stronger partnership between the public and private sectors must be developed. Given the increasing availability of assisted reproductive technologies in the sub-Saharan Africa region, and the tendency to locate these technologies in the private sector, further research is needed to understand and identify the processes underlying the implementation of fertility care and to foster better integration with the existing health system.


Asunto(s)
Preservación de la Fertilidad , Infertilidad , Humanos , Gambia , África Occidental , Infertilidad/terapia , Fertilidad
13.
BMJ Glob Health ; 9(2)2024 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341190

RESUMEN

BACKGROUND: Attempts to understand biosocial phenomena using scientific methods are often presented as value-neutral and objective; however, when used to reduce the complexity of open systems such as epidemics, these forms of inquiry necessarily entail normative considerations and are therefore fashioned by political worldviews (ideologies). From the standpoint of poststructural theory, the character of these representations is at most limited and partial. In addition, these modes of representation (as stories) do work (as technologies) in the service of, or in resistance to, power. METHODS: We focus on a single Ebola case cluster from the 2013-2016 outbreak in West Africa and examine how different disciplinary forms of knowledge production (including outbreak forecasting, active epidemiological surveillance, post-outbreak serosurveys, political economic analyses, and ethnography) function as Story Technologies. We then explore how these technologies are used to curate 'data,' analysing the erasures, values, and imperatives evoked by each. RESULTS: We call attention to the instrumental-in addition to the descriptive-role Story Technologies play in ordering contingencies and establishing relationships in the wake of health crises. DISCUSSION: By connecting each type of knowledge production with the systems of power it reinforces or disrupts, we illustrate how Story Technologies do ideological work. These findings encourage research from pluriversal perspectives and advocacy for measures that promote more inclusive modes of knowledge production.


Asunto(s)
Epidemias , Fiebre Hemorrágica Ebola , Humanos , Fiebre Hemorrágica Ebola/epidemiología , Brotes de Enfermedades/prevención & control , África Occidental/epidemiología , Antropología Cultural
14.
Science ; 383(6685): 810-816, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38386723

RESUMEN

Long neglected, Lassa fever is surging in West Africa. Researchers want to know why.


Asunto(s)
Fiebre de Lassa , Enfermedades Desatendidas , Humanos , África Occidental/epidemiología , Fiebre de Lassa/epidemiología , Enfermedades Desatendidas/epidemiología
15.
Microbiol Spectr ; 12(4): e0309823, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38407984

RESUMEN

Ebola virus (EBOV) infection is threatening human health, especially in Central and West Africa. Limited clinical trials and the requirement of biosafety level-4 laboratories hinder experimental work to advance our understanding of EBOV and the evaluation of treatment. In this work, we use a computational model to study the assembly and budding process of EBOV and evaluate the effect of fendiline on these processes in the context of fluctuating host membrane lipid levels. Our results demonstrate for the first time that the assembly of VP40 filaments may follow the nucleation-elongation theory, as this mechanism is critical to maintaining a pool of VP40 dimers for the maturation and production of virus-like particles (VLPs). We further find that this nucleation-elongation process is likely influenced by fluctuating phosphatidylserine (PS), which can complicate the efficacy of lipid-targeted therapies like fendiline, a drug that lowers cellular PS levels. Our results indicate that fendiline-induced PS reduction may actually increase VLP production at earlier time points (24 h) and under low fendiline concentrations (≤2 µM). However, this effect is transient and does not change the conclusion that fendiline generally decreases VLP production. In the context of fluctuating PS levels, we also conclude that fendiline can be more efficient at the late stage of VLP budding relative to earlier phases. Combination therapy with a VLP budding step-targeted drug may therefore further increase the treatment efficiency of fendiline. Finally, we also show that fendiline-induced PS reduction more effectively lowers VLP production when VP40 expression is high. Taken together, our results provide critical quantitative information on how fluctuating lipid levels (PS) affect EBOV assembly and egress and how this mechanism can be disrupted by lipid-targeting molecules like fendiline. IMPORTANCE: Ebola virus (EBOV) infection can cause deadly hemorrhagic fever, which has a mortality rate of ~50%-90% without treatment. The recent outbreaks in Uganda and the Democratic Republic of the Congo illustrate its threat to human health. Though two antibody-based treatments were approved, mortality rates in the last outbreak were still higher than 30%. This can partly be due to the requirement of advanced medical facilities for current treatments. As a result, it is very important to develop and evaluate new therapies for EBOV infection, especially those that can be easily applied in the developing world. The significance of our research is that we evaluate the potential of lipid-targeted treatments in reducing EBOV assembly and egress. We achieved this goal using the VP40 system combined with a computational approach, which both saves time and lowers cost compared to traditional experimental studies and provides innovative new tools to study viral protein dynamics.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Humanos , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Ebolavirus/genética , Fendilina/metabolismo , Lípidos , África Occidental
16.
Viruses ; 16(2)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38400041

RESUMEN

Lassa virus (LASV) is a zoonotic pathogen endemic throughout western Africa and is responsible for a human disease known as Lassa fever (LF). Historically, LASV has been emphasized as one of the greatest public health threats in West Africa, with up to 300,000 cases and 5000 associated deaths per year. This, and the fact that the disease has been reported in travelers, has driven a rapid production of various vaccine candidates. Several of these vaccines are currently in clinical development, despite limitations in understanding the immune response to infection. Alarmingly, the host immune response has been implicated in the induction of sensorineural hearing loss in LF survivors, legitimately raising safety questions about any future vaccines as well as efficacy in preventing potential hearing loss. The objective of this article is to revisit the importance and prevalence of LF in West Africa, with focus on Nigeria, and discuss current therapeutic approaches and ongoing vaccine development. In addition, we aim to emphasize the need for more scientific studies relating to LF-associated hearing loss, and to promote critical discussion about potential risks and benefits of vaccinating the population in endemic regions of West Africa.


Asunto(s)
Pérdida Auditiva Sensorineural , Fiebre de Lassa , Vacunas Virales , Humanos , Fiebre de Lassa/epidemiología , Fiebre de Lassa/prevención & control , Virus Lassa , África Occidental/epidemiología , Manejo de la Enfermedad
17.
Vaccine ; 42(8): 1873-1877, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38369392

RESUMEN

Lassa fever (LF) is a zoonotic viral hemorrhagic disease endemic to several West African countries. Approximately 300-500,000 cases occur annually across all ages with 10-20% case fatality rates. A LF vaccine is a recognized public health priority, with several candidates entering clinical trials. However, the perspectives of regional experts regarding critical vaccine properties, ideal delivery methods, and priority target populations remain unclear. Using a mixed methods approach with a standardized questionnaire, we individually interviewed 8 West African stakeholders, each with extensive knowledge and experience of LF. They strongly favored the use of a mass, proactive campaign strategy to immunize a wide age range of people in high-risk areas, including pregnant women and health care workers. We estimated that these and other plausible delivery scenarios could result in an initial demand of anywhere from 1 to 100 million doses, with most demand coming from Nigeria. These findings may help inform LF vaccine development and deployment efforts.


Asunto(s)
Fiebre de Lassa , Vacunas Virales , Humanos , Femenino , Embarazo , Fiebre de Lassa/epidemiología , Fiebre de Lassa/prevención & control , Virus Lassa , África Occidental/epidemiología , Nigeria/epidemiología
18.
BMC Public Health ; 24(1): 450, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38347490

RESUMEN

BACKGROUND: Malaria is one of the major vector-borne diseases most sensitive to climatic change in West Africa. The prevention and reduction of malaria are very difficult in Benin due to poverty, economic insatiability and the non control of environmental determinants. This study aims to develop an intelligent outbreak malaria early warning model driven by monthly time series climatic variables in the northern part of Benin. METHODS: Climate data from nine rain gauge stations and malaria incidence data from 2009 to 2021 were extracted from the National Meteorological Agency (METEO) and the Ministry of Health of Benin, respectively. Projected relative humidity and temperature were obtained from the coordinated regional downscaling experiment (CORDEX) simulations of the Rossby Centre Regional Atmospheric regional climate model (RCA4). A structural equation model was employed to determine the effects of climatic variables on malaria incidence. We developed an intelligent malaria early warning model to predict the prevalence of malaria using machine learning by applying three machine learning algorithms, including linear regression (LiR), support vector machine (SVM), and negative binomial regression (NBiR). RESULTS: Two ecological factors such as factor 1 (related to average mean relative humidity, average maximum relative humidity, and average maximal temperature) and factor 2 (related to average minimal temperature) affect the incidence of malaria. Support vector machine regression is the best-performing algorithm, predicting 82% of malaria incidence in the northern part of Benin. The projection reveals an increase in malaria incidence under RCP4.5 and RCP8.5 over the studied period. CONCLUSION: These results reveal that the northern part of Benin is at high risk of malaria, and specific malaria control programs are urged to reduce the risk of malaria.


Asunto(s)
Malaria , Humanos , Benin/epidemiología , Malaria/epidemiología , Malaria/prevención & control , Temperatura , Incidencia , África Occidental/epidemiología , Brotes de Enfermedades/prevención & control
19.
PLoS One ; 19(2): e0297983, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38330000

RESUMEN

Tomato is one of the most appreciated vegetables in the world. Predicting its yield and optimizing its culture is important for global food security. This paper addresses the challenge of finding optimum climatic values for a high tomato yield. The Frequent Pattern Growth (FPG) algorithm was considered to establish the associations between six climate variables: minimum and maximum temperatures, maximum humidity, sunshine (Sun), rainfall, and evapotranspiration (ET), collected over 26 years in the three agro-ecological Zones of Benin. Monthly climate data were aggregated with yield data over the same period. After aggregation, the data were transformed into 'low', 'medium', and 'high' attributes using the threshold values defined. Then, the rules were generated using the minimum support set to 0.2 and the confidence to 0.8. Only the rules with the consequence 'high yield' were screened. The best yield patterns were observed in the Guinean Zone, followed by the Sudanian. The results indicated that high tomato yield was associated with low ET in all areas considered. Minimum and maximum temperatures, maximum humidity, and Sun were medium in every Zone. Moreover, rainfall was high in the Sudanian Zone, unlike the other regions where it remained medium. These results are useful in assessing climate variability's impact on tomato production. Thus, they can help farmers make informed decisions on cultivation practices to optimize production in a changing environment. In addition, the findings of this study can be considered in other regions and adapted to other crops.


Asunto(s)
Solanum lycopersicum , Benin , África Occidental , Humedad , Temperatura
20.
J Ethnobiol Ethnomed ; 20(1): 15, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336725

RESUMEN

BACKGROUND: Several hypotheses have been used in ethnobotany to explain the plant's selection criteria by people for their daily needs. Thus, it is important to assess synergy and complementarity among them, especially, those concerning the plant use value, social dynamics and human traits. The study aims to (i) highlight people's socio-economic factors, and plant ecological traits that affect the plant use-availability dynamic (PUD); and (ii) assess the available species diversity effect on ethno-medicinal knowledge diversity in Benin. METHODS: Ethnobotanical interviews were carried out to quantify the importance of local species in different ecological zones of Benin with 590 traditional medicine actors. Vegetation surveys were done to assess species availability within 337 plots of 50 m x 40 m or 60 m x 30 m, depending on the climatic zone, for a total of 61.6 ha, established in 15 forests distributed within the 10 phytodistricts of Benin. The plant use availability hypothesis was quantified as a dynamic link between species use value and availability (PUD). A general and mixed linear models were used to assess the significance of each factor's effect on PUD. Pearson correlation test was applied on Shannon diversity index considering inventoried species in the field and those which were cited by people, for the available species diversity effect on ethno-medicinal knowledge diversity assessment. RESULTS: A hundred and twenty woody medicinal plants, mostly trees (68.33%), were sampled. Growth form and its interaction with phytodistrict have a significant effect (p: 0.005) on PUD. The less available trees were the most used in the phytodistricts 3, 4, 8 and 10. PUD varies significantly according to social factors (p: 0.007). Ethnicity, age and main activity were the most quoted social factors which influenced the PUD. Ethnicity and age have various effects considering the phytodistricts. Moreover, the influence of age changes following the main activity. Plant selection did not solely link to the surrounding diversity (r: - 0.293; p: 0.403). Within some phytodistricts, especially those of 3, 4, 8 and 10, the less available tree species were the most requested. CONCLUSION: It is urgent to reforest vegetation patches in some phytodistricts (3, 4, 8 and 10) of Benin with widely requested and no available species to avoid the extinction of their wild populations. This concerns Cassia sieberiana DC., Anonychium africanum (Guill. & Perr.) C. E.Hughes & G. P. Lewis, Pterocarpus erinaceus Poir., Cola millenii K. Schum., Azadirachta indica A. Juss., Khaya senegalensis (Desr.) A. Juss., Pseudocedrela kotschyi (Schweinf.) Harms, Treculia africana Decne. ex Trécul, Uapaca heudelotii Baill., Vitellaria paradoxa C. F. Gaertn., Kigelia africana (Lam.) Benth. and Newbouldia laevis (P. Beauv.) Seem. ex Bureau.


Asunto(s)
Conservación de los Recursos Naturales , Plantas Medicinales , Humanos , Benin , Etnobotánica , África Occidental , Árboles , Etnicidad , Dinámica de Grupo
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