RESUMO
The 2013-2016 outbreak of Ebola virus (EBOV) in West Africa was the largest recorded. It began following the cross-species transmission of EBOV from an animal reservoir, most likely bats, into humans, with phylogenetic analysis revealing the co-circulation of several viral lineages. We hypothesized that this prolonged human circulation led to genomic changes that increased viral transmissibility in humans. We generated a synthetic glycoprotein (GP) construct based on the earliest reported isolate and introduced amino acid substitutions that defined viral lineages. Mutant GPs were used to generate a panel of pseudoviruses, which were used to infect different human and bat cell lines. These data revealed that specific amino acid substitutions in the EBOV GP have increased tropism for human cells, while reducing tropism for bat cells. Such increased infectivity may have enhanced the ability of EBOV to transmit among humans and contributed to the wide geographic distribution of some viral lineages.
Assuntos
Evolução Biológica , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/virologia , Especificidade de Hospedeiro , África Ocidental/epidemiologia , Animais , Quirópteros/virologia , Surtos de Doenças , Ebolavirus/classificação , Ebolavirus/genética , Ebolavirus/patogenicidade , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/transmissão , Humanos , Mutação , Filogenia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , ZoonosesRESUMO
The explosive emergence of Zika virus (ZIKV) across the Pacific and Americas since 2007 was associated with hundreds of thousands of human cases and severe outcomes, including congenital microcephaly caused by ZIKV infection during pregnancy. Although ZIKV was first isolated in Uganda, Africa has so far been exempt from large-scale ZIKV epidemics, despite widespread susceptibility among African human populations. A possible explanation for this pattern is natural variation among populations of the primary vector of ZIKV, the mosquito Aedes aegypti. Globally invasive populations of Ae. aegypti outside of Africa are considered effective ZIKV vectors because they are human specialists with high intrinsic ZIKV susceptibility, whereas African populations of Ae. aegypti across the species' native range are predominantly generalists with low intrinsic ZIKV susceptibility, making them less likely to spread viruses in the human population. We test this idea by studying a notable exception to the patterns observed across most of Africa: Cape Verde experienced a large ZIKV outbreak in 2015 to 2016. We find that local Ae. aegypti in Cape Verde have substantial human-specialist ancestry, show a robust behavioral preference for human hosts, and exhibit increased susceptibility to ZIKV infection, consistent with a key role for variation among mosquito populations in ZIKV epidemiology. These findings suggest that similar human-specialist populations of Ae. aegypti in the nearby Sahel region of West Africa, which may be expanding in response to rapid urbanization, could serve as effective vectors for ZIKV in the future.
Assuntos
Aedes , Epidemias , Infecção por Zika virus , Zika virus , Animais , Humanos , Zika virus/fisiologia , Cabo Verde , Saliva , Mosquitos VetoresRESUMO
In January 2021, Senegal reported the emergence of highly pathogenic avian influenza virus A(H5N1), which was detected on a poultry farm in Thies, Senegal, and in great white pelicans in the Djoudj National Bird Sanctuary. We report evidence of new transcontinental spread of H5N1 from Europe toward Africa.
Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Influenza Humana , Animais , Aves , Humanos , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Aves Domésticas , Senegal/epidemiologiaRESUMO
Zika virus (ZIKV) is an arbovirus belonging to the genus Flavivirus (family Flaviviridae) and was first described in 1947 in Uganda following blood analyses of sentinel Rhesus monkeys. Until the twentieth century, the African and Asian lineages of the virus did not cause meaningful infections in humans. However, in 2007, vectored by Aedes aegypti mosquitoes, ZIKV caused the first noteworthy epidemic on the Yap Island in Micronesia. Patients experienced fever, skin rash, arthralgia and conjunctivitis. From 2013 to 2015, the Asian lineage of the virus caused further massive outbreaks in New Caledonia and French Polynesia. In 2013, ZIKV reached Brazil, later spreading to other countries in South and Central America. In Brazil, the virus has been linked to congenital malformations, including microcephaly and other severe neurological diseases, such as Guillain-Barré syndrome. Despite clinical evidence, direct experimental proof showing that the Brazilian ZIKV (ZIKV(BR)) strain causes birth defects remains absent. Here we demonstrate that ZIKV(BR) infects fetuses, causing intrauterine growth restriction, including signs of microcephaly, in mice. Moreover, the virus infects human cortical progenitor cells, leading to an increase in cell death. We also report that the infection of human brain organoids results in a reduction of proliferative zones and disrupted cortical layers. These results indicate that ZIKV(BR) crosses the placenta and causes microcephaly by targeting cortical progenitor cells, inducing cell death by apoptosis and autophagy, and impairing neurodevelopment. Our data reinforce the growing body of evidence linking the ZIKV(BR) outbreak to the alarming number of cases of congenital brain malformations. Our model can be used to determine the efficiency of therapeutic approaches to counteracting the harmful impact of ZIKV(BR) in human neurodevelopment.
Assuntos
Modelos Animais de Doenças , Microcefalia/virologia , Zika virus/patogenicidade , Animais , Apoptose , Autofagia , Encéfalo/patologia , Encéfalo/virologia , Brasil/epidemiologia , Proliferação de Células , Feminino , Retardo do Crescimento Fetal/patologia , Retardo do Crescimento Fetal/virologia , Feto/virologia , Camundongos , Microcefalia/epidemiologia , Microcefalia/etiologia , Microcefalia/patologia , Células-Tronco Neurais/patologia , Células-Tronco Neurais/virologia , Organoides/patologia , Organoides/virologia , Placenta/virologia , Gravidez , Infecção por Zika virus/complicações , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/patologia , Infecção por Zika virus/virologiaRESUMO
We investigated the dynamics of seroconversion in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. During March 29-May 22, 2020, we collected serum samples and associated clinical data from 177 persons in London, UK, who had SARS-CoV-2 infection. We measured IgG against SARS-CoV-2 and compared antibody levels with patient outcomes, demographic information, and laboratory characteristics. We found that 2.0%-8.5% of persons did not seroconvert 3-6 weeks after infection. Persons who seroconverted were older, were more likely to have concurrent conditions, and had higher levels of inflammatory markers. Non-White persons had higher antibody concentrations than those who identified as White; these concentrations did not decline during follow-up. Serologic assay results correlated with disease outcome, race, and other risk factors for severe SARS-CoV-2 infection. Serologic assays can be used in surveillance to clarify the duration and protective nature of humoral responses to SARS-CoV-2 infection.
Assuntos
COVID-19/sangue , COVID-19/imunologia , Imunoglobulina G/sangue , SARS-CoV-2 , Soroconversão , Adulto , Idoso , Anticorpos Antivirais/sangue , COVID-19/fisiopatologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
In March 2020, the SARS-CoV-2 virus outbreak was declared as a world pandemic by the World Health Organization (WHO). The only measures for controlling the outbreak are testing and isolation of infected cases. Molecular real-time polymerase chain reaction (PCR) assays are very sensitive but require highly equipped laboratories and well-trained personnel. In this study, a rapid point-of-need detection method was developed to detect the RNA-dependent RNA polymerase (RdRP), envelope protein (E), and nucleocapsid protein (N) genes of SARS-CoV-2 based on the reverse transcription recombinase polymerase amplification (RT-RPA) assay. RdRP, E, and N RT-RPA assays required approximately 15 min to amplify 2, 15, and 15 RNA molecules of molecular standard/reaction, respectively. RdRP and E RT-RPA assays detected SARS-CoV-1 and 2 genomic RNA, whereas the N RT-RPA assay identified only SARS-CoV-2 RNA. All established assays did not cross-react with nucleic acids of other respiratory pathogens. The RT-RPA assay's clinical sensitivity and specificity in comparison to real-time RT-PCR (n = 36) were 94 and 100% for RdRP; 65 and 77% for E; and 83 and 94% for the N RT-RPA assay. The assays were deployed to the field, where the RdRP RT-RPA assays confirmed to produce the most accurate results in three different laboratories in Africa (n = 89). The RPA assays were run in a mobile suitcase laboratory to facilitate the deployment at point of need. The assays can contribute to speed up the control measures as well as assist in the detection of COVID-19 cases in low-resource settings.
Assuntos
COVID-19/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Recombinases/metabolismo , SARS-CoV-2/isolamento & purificação , COVID-19/virologia , Humanos , Sensibilidade e EspecificidadeRESUMO
An epidemic of Ebola virus disease of unprecedented scale has been ongoing for more than a year in West Africa. As of 29 April 2015, there have been 26,277 reported total cases (of which 14,895 have been laboratory confirmed) resulting in 10,899 deaths. The source of the outbreak was traced to the prefecture of Guéckédou in the forested region of southeastern Guinea. The virus later spread to the capital, Conakry, and to the neighbouring countries of Sierra Leone, Liberia, Nigeria, Senegal and Mali. In March 2014, when the first cases were detected in Conakry, the Institut Pasteur of Dakar, Senegal, deployed a mobile laboratory in Donka hospital to provide diagnostic services to the greater Conakry urban area and other regions of Guinea. Through this process we sampled 85 Ebola viruses (EBOV) from patients infected from July to November 2014, and report their full genome sequences here. Phylogenetic analysis reveals the sustained transmission of three distinct viral lineages co-circulating in Guinea, including the urban setting of Conakry and its surroundings. One lineage is unique to Guinea and closely related to the earliest sampled viruses of the epidemic. A second lineage contains viruses probably reintroduced from neighbouring Sierra Leone on multiple occasions, while a third lineage later spread from Guinea to Mali. Each lineage is defined by multiple mutations, including non-synonymous changes in the virion protein 35 (VP35), glycoprotein (GP) and RNA-dependent RNA polymerase (L) proteins. The viral GP is characterized by a glycosylation site modification and mutations in the mucin-like domain that could modify the outer shape of the virion. These data illustrate the ongoing ability of EBOV to develop lineage-specific and potentially phenotypically important variation.
Assuntos
Ebolavirus/genética , Variação Genética/genética , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/virologia , Mutação/genética , Filogenia , Ebolavirus/isolamento & purificação , Evolução Molecular , Genoma Viral/genética , Glicoproteínas/genética , Glicoproteínas/metabolismo , Glicosilação , Guiné/epidemiologia , Doença pelo Vírus Ebola/transmissão , Humanos , Mali/epidemiologia , Dados de Sequência Molecular , Mucinas/química , Proteínas do Nucleocapsídeo , Nucleoproteínas/genética , Estrutura Terciária de Proteína/genética , RNA Polimerase Dependente de RNA/genética , Serra Leoa/epidemiologia , Proteínas do Core Viral/genéticaRESUMO
Hantaviruses cause hemorrhagic fever in humans worldwide. However, few hantavirus surveillance campaigns occur in Africa. We detected Seoul orthohantavirus in black rats in Senegal, although we did not find serologic evidence of this disease in humans. These findings highlight the need for increased surveillance of hantaviruses in this region.
Assuntos
Infecções por Hantavirus , Febre Hemorrágica com Síndrome Renal , Orthohantavírus , Vírus Seoul , Orthohantavírus/genética , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/veterinária , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/veterinária , Humanos , Ratos , Senegal/epidemiologia , Seul , Vírus Seoul/genéticaRESUMO
BACKGROUND: In the wake of the recent outbreak of Ebola virus disease (EVD) in several African countries, the World Health Organization prioritized the evaluation of treatment with convalescent plasma derived from patients who have recovered from the disease. We evaluated the safety and efficacy of convalescent plasma for the treatment of EVD in Guinea. METHODS: In this nonrandomized, comparative study, 99 patients of various ages (including pregnant women) with confirmed EVD received two consecutive transfusions of 200 to 250 ml of ABO-compatible convalescent plasma, with each unit of plasma obtained from a separate convalescent donor. The transfusions were initiated on the day of diagnosis or up to 2 days later. The level of neutralizing antibodies against Ebola virus in the plasma was unknown at the time of administration. The control group was 418 patients who had been treated at the same center during the previous 5 months. The primary outcome was the risk of death during the period from 3 to 16 days after diagnosis with adjustments for age and the baseline cycle-threshold value on polymerase-chain-reaction assay; patients who had died before day 3 were excluded. The clinically important difference was defined as an absolute reduction in mortality of 20 percentage points in the convalescent-plasma group as compared with the control group. RESULTS: A total of 84 patients who were treated with plasma were included in the primary analysis. At baseline, the convalescent-plasma group had slightly higher cycle-threshold values and a shorter duration of symptoms than did the control group, along with a higher frequency of eye redness and difficulty in swallowing. From day 3 to day 16 after diagnosis, the risk of death was 31% in the convalescent-plasma group and 38% in the control group (risk difference, -7 percentage points; 95% confidence interval [CI], -18 to 4). The difference was reduced after adjustment for age and cycle-threshold value (adjusted risk difference, -3 percentage points; 95% CI, -13 to 8). No serious adverse reactions associated with the use of convalescent plasma were observed. CONCLUSIONS: The transfusion of up to 500 ml of convalescent plasma with unknown levels of neutralizing antibodies in 84 patients with confirmed EVD was not associated with a significant improvement in survival. (Funded by the European Union's Horizon 2020 Research and Innovation Program and others; ClinicalTrials.gov number, NCT02342171.).
Assuntos
Transfusão de Componentes Sanguíneos , Doença pelo Vírus Ebola/terapia , Plasma , Adolescente , Adulto , Anticorpos Neutralizantes/sangue , Transfusão de Componentes Sanguíneos/efeitos adversos , Criança , Pré-Escolar , Convalescença , Ebolavirus/imunologia , Feminino , Guiné , Doença pelo Vírus Ebola/mortalidade , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Razão de Chances , Plasma/imunologia , Gravidez , Adulto JovemRESUMO
Background: A mobile laboratory transportable on commercial flights was developed to enable local response to viral hemorrhagic fever outbreaks. Methods: The development progressed from use of mobile real-time reverse-transcription polymerase chain reaction to mobile real-time recombinase polymerase amplification. In this study, we describe various stages of the mobile laboratory development. Results: A brief overview of mobile laboratory deployments, which culminated in the first on-site detection of Ebola virus disease (EVD) in March 2014, and their successful use in a campaign to roll back EVD cases in Conakry in the West Africa Ebola virus outbreak are described. Conclusions: The developed mobile laboratory successfully enabled local teams to perform rapid disgnostic testing for viral hemorrhagic fever.
Assuntos
Doença pelo Vírus Ebola/diagnóstico , Laboratórios , Unidades Móveis de Saúde , Sistemas Automatizados de Assistência Junto ao Leito , África Ocidental , Ebolavirus/genética , Doença pelo Vírus Ebola/virologia , Humanos , Tipagem Molecular/instrumentação , RNA Viral/sangue , Reação em Cadeia da Polimerase em Tempo Real/instrumentaçãoRESUMO
BACKGROUND: Malaria in Senegal is due essentially to infections by Plasmodium falciparum and, to a lesser extent to Plasmodium malariae and Plasmodium ovale. By the use of molecular methods, detection of Plasmodium vivax has been recently reported in the region of Kedougou, raising the question of appraisal of its potential prevalence in this setting. METHODS: A retrospective serological study was carried out using 188 samples taken from 2010 to 2011 in a longitudinal school survey during which 48 asymptomatic children (9-11 years) were recruited. Four collections of samples collected during two successive dry and rainy seasons were analysed for antibody responses to P. vivax and P. falciparum. Recombinant P. falciparum and P. vivax MSP1 antigens and total P. falciparum schizont lysate from African 07/03 strain (adapted to culture) were used for ELISA. Nested PCR amplification was used for molecular detection of P. vivax. RESULTS: A surprising high prevalence of IgG responses against P. vivax MSP1 was evidenced with 53% of positive samples and 58% of the individuals that were found positive to this antigen. There was 77% of responders to P. falciparum outlined by 63% of positive samples. Prevalence of responders did not differ as function of seasons. Levels of antibodies to P. falciparum fluctuated with significant increasing between dry and rainy season (P < 0.05), contrary to responses to P. vivax. There was a significant reciprocal relationship (P < 10-3) between antibody responses to the different antigens, but with weak coefficient of correlation (Rho around 0.3) underlining a variable profile at the individual level. Clear molecular signature was found in positive IgG to P. vivax msp1 samples by PCR. CONCLUSION: This cross-sectional longitudinal study highlights the unexpected high circulation of P. vivax in this endemic area. Sero-immunology and molecular methods are powerful additive tools to identify endemic sites where relevant control measures have to be settled and monitored.
Assuntos
Anticorpos Antiprotozoários/sangue , Infecções Assintomáticas/epidemiologia , Malária Vivax/sangue , Malária Vivax/epidemiologia , Plasmodium vivax/isolamento & purificação , Criança , Estudos Transversais , DNA de Protozoário/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Estudos Longitudinais , Malária Falciparum/sangue , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Malária Vivax/imunologia , Malária Vivax/parasitologia , Masculino , Plasmodium falciparum/genética , Plasmodium vivax/genética , Plasmodium vivax/imunologia , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos , Senegal/epidemiologia , Testes SorológicosRESUMO
The incidence of breast cancer (BC) is rising worldwide, with an increase in aggressive neoplasias in young women. Traditionally, BC in young women has been thought to be etiologically driven, primarily by genetic/hereditary factors. However, these factors explain only a small proportion of BCs, pointing to a role of the environment. Suspected factors responsible for this increase include lifestyle changes, notably alcohol consumption, diet with high intake of refined carbohydrates and saturated fat and low intake of polyunsaturated fatty acids (PUFA), fiber and vitamins (such as folate, vitamin D, and carotenoids), low physical activity, and body fatness, all of which may act from childhood and adolescent years through adulthood. Despite limited data on BC in young women, evidence points to the importance of a healthy lifestyle, including high intake of vegetables, fruits, legumes, fish, and poultry, low intake of sugar and fat, daily physical activity, low alcohol consumption, steady weight, and breastfeeding in preventing BC in young women. Preventive efforts should begin in early life to provide important benefits much later in life by shifting the long-term trajectory of risk accumulation. Data from Latin America and developing regions are still sparse. There is a need to harmonize studies in a global effort to fight the rise of BC incidence in low- and middle-income countries, where the nutritional transition is occurring rapidly. The stratification of BC by specific tumor characteristics needs to be considered since risk factors may be more particularly associated with the promotion of, or protection from, a defined type of BC.
Assuntos
Neoplasias da Mama/epidemiologia , Dieta , Estilo de Vida , Tecido Adiposo/fisiologia , Adulto , Idade de Início , Aleitamento Materno , Neoplasias da Mama/etiologia , Neoplasias da Mama/genética , Exercício Físico/fisiologia , Feminino , Saúde Global , Humanos , Fatores de RiscoRESUMO
In October 2015, a new case of Ebola virus disease in Guinea was detected. Case investigation, serology, and whole-genome sequencing indicated possible transmission of the virus from an Ebola virus disease survivor to another person and then to the case-patient reported here. This transmission chain over 11 months suggests slow Ebola virus evolution.
Assuntos
Surtos de Doenças , Ebolavirus , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/transmissão , Criança , Ebolavirus/classificação , Ebolavirus/genética , Feminino , Guiné/epidemiologia , Doença pelo Vírus Ebola/história , Doença pelo Vírus Ebola/virologia , História do Século XXI , Humanos , Masculino , Filogenia , Vigilância da População , Estudos SoroepidemiológicosRESUMO
In countries from which Crimean-Congo haemorrhagic fever (CCHF) is absent, the causative virus, CCHF virus (CCHFV), is classified as a hazard group 4 agent and handled in containment level (CL)-4. In contrast, most endemic countries out of necessity have had to perform diagnostic tests under biosafety level (BSL)-2 or -3 conditions. In particular, Turkey and several of the Balkan countries have safely processed more than 100 000 samples over many years in BSL-2 laboratories. It is therefore advocated that biosafety requirements for CCHF diagnostic procedures should be revised, to allow the tests required to be performed under enhanced BSL-2 conditions with appropriate biosafety laboratory equipment and personal protective equipment used according to standardized protocols in the countries affected. Downgrading of CCHFV research work from CL-4, BSL-4 to CL-3, BSL-3 should also be considered.
Assuntos
Contenção de Riscos Biológicos/normas , Vírus da Febre Hemorrágica da Crimeia-Congo/fisiologia , Febre Hemorrágica da Crimeia/prevenção & controle , Exposição Ocupacional/prevenção & controle , Animais , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/virologia , Humanos , Exposição Ocupacional/normasAssuntos
Infecções por Coronavirus/prevenção & controle , Doenças Endêmicas , Malária/epidemiologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissãoRESUMO
BACKGROUND: Concurrent malaria and arbovirus infections are common and represent an important public health concern in regions where both diseases are endemic. The present study investigates the genetic diversity and complexity of Plasmodium falciparum infection in concurrent malaria-arbovirus infections in Kedougou region, southeastern Senegal. METHODS: Parasite DNA was extracted from 60 to 27 sera samples collected from P. falciparum isolates of malaria and concurrent malaria-arbovirus infected patients, respectively, and followed by PCR-genotyping targeting the msp-1 (block2) and msp-2 (block3) allelic families. RESULTS: The mean number of genotype per allelic family was comparable between the two groups. K1 was the predominant msp-1 allelic type both in malaria (94.91%) and arbovirus-malaria (92.59%) groups, whereas IC/3D7 was the most prevalent msp-2 allelic type in malaria (94.91%) and arbovirus-malaria (96.29%) groups. Frequencies of msp-1 and msp-2 allelic types were statistically comparable between the two groups (Fisher exact test, P > 0.05) and were not associated with age. FC27 was strikingly the least prevalent in both groups and was absent in children under 5 years of age. The proportions of P. falciparum isolates from malaria-infected patients carrying the three msp-1 allelic types (67.44%) or the two msp-2 allelic types (76.47%) were significantly higher than those from arbovirus-malaria co-infected patients (Exact binomial test, P < 0.05). The multiplicities of infection (MOI) were low and comparable for msp-1 (1.19 vs 1.22) and msp-2 (1.11 vs 1.10), respectively between malaria and arbovirus-malaria groups. CONCLUSION: The study showed no difference in the genetic diversity between P. falciparum isolates from malaria and concurrent malaria-arbovirus infected patients in Kedougou. The MOI was low despite intense malaria transmission in Kedougou. The overall results suggest a limited or no influence of arbovirus infections on P. falciparum diversity and complexity of malaria infection.
Assuntos
Infecções por Arbovirus/complicações , Coinfecção/parasitologia , Variação Genética , Malária Falciparum/complicações , Malária Falciparum/parasitologia , Plasmodium falciparum/classificação , Plasmodium falciparum/genética , Adolescente , Adulto , Antígenos de Protozoários/genética , Criança , Pré-Escolar , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Lactente , Masculino , Proteína 1 de Superfície de Merozoito/genética , Pessoa de Meia-Idade , Plasmodium falciparum/isolamento & purificação , Reação em Cadeia da Polimerase , Proteínas de Protozoários/genética , Senegal , Adulto JovemRESUMO
The livelihoods of the Fulani mobile pastoralists in the Sahel, West and Central Africa are characterised by mobility (related to the needs of their animals), extensive social networks, and a focus on social ties as the basis of status and influence ('wealth in people'). The Sahel environment in which many Fulani nomads live has become embroiled in jihadism, conflict, and violence; at the same time, this region has experienced an increase in opportunities to connect through the wireless mobile communication system. This paper analyses the triangle of mobility, communication, and insecurity in order to understand the present-day situation of the nomadic and semi-nomadic Fulani pastoralists and their identity dynamics. The Fulani find themselves caught in between these conflicts, which end their mobility and often lead to the loss of their herds. Will they be able to keep their mobile lifestyle and identity? This article is based on qualitative case studies and the biographical narratives of nomadic and semi-nomadic pastoralists who have lived through conflict and violence in Cameroon, Chad and Mali. These case studies show that, despite the fact that mobile pastoralism has become difficult as a consequence of the conflicts and loss of cattle, the 'mobile' identity is very present and reinforced with the help of mobile telephony, through which social networks and 'wealth in people' are sustained.
Au Sahel et en Afrique centrale et de l'Ouest, les moyens de subsistance des pasteurs nomades peuls se définissent par la mobilité (liée aux besoins de leurs troupeaux), par des réseaux sociaux extensifs et par l'importance des liens sociaux en tant que base du prestige et de l'influence des individus (le « patrimoine relationnel ¼ fondé sur les liens personnels). Le Sahel où vivent nombre de nomades peuls se trouve actuellement entraîné dans le djihadisme, les conflits et la violence ; en même temps, cette région offre désormais bien plus de possibilités de se connecter grâce à la technologie de la communication mobile non filaire. Les auteurs analysent les interactions entre la mobilité, la communication et l'insécurité afin de mieux comprendre la situation actuelle des pasteurs peuls nomades et semi-nomades ainsi que leur dynamique identitaire. Les Peuls se retrouvent au coeur de conflits qui mettent fin à leur mobilité et entraînent souvent la destruction de leurs troupeaux. Pourront-ils garder leur mode de vie et leur identité nomade ? L'analyse présentée dans cet article repose sur des études de cas qualitatives et des récits de vie recueillis auprès de pasteurs nomades et semi-nomades qui ont été confrontés à des conflits et à la violence, au Cameroun, au Tchad et au Mali. Il ressort de ces études que si le pastoralisme nomade devient plus difficile en raison des conflits et des pertes de bétail, l'identité « mobile ¼ (ou nomade) reste très présente et se voit renforcée par la téléphonie mobile qui permet notamment de pérenniser les liens à la base du patrimoine relationnel ainsi que les réseaux sociaux.
Los medios de sustento de los pastores nómadas Fulani (o peul, o fulbe) del Sahel, África Central y África Occidental se caracterizan por la movilidad (ligada a las necesidades de sus animales), por extensas redes de sociabilidad y por el lugar central que ocupan los vínculos sociales como fundamento del rango y la influencia de la persona («grado de riqueza en gente¼). El medio saheliano en el que viven muchos nómadas fulani se ha convertido hoy en un avispero de jihadismo, conflictos y violencia. Al mismo tiempo, la región conoce ahora un auge de las posibilidades de conexión gracias a los sistemas móviles de comunicación inalámbrica. Los autores analizan el triángulo formado por la movilidad, la comunicación y la inseguridad con el fin de aprehender la situación actual de los pastores fulani nómadas y seminómadas y su dinámica identitaria. El hecho de que los fulani se vean atrapados en esos conflictos coarta su movilidad y acarrea a menudo la pérdida de sus rebaños. ¿Serán capaces de mantener su modo de vida y su identidad, enraizados en el nomadismo? Los autores se basan aquí en estudios monográficos cualitativos y en historias biográficas recogidas entre y con pastores nómadas y seminómadas del Camerún, el Chad y Malí que han tenido que convivir con conflictos y violencia. Estos estudios monográficos evidencian que, si bien el pastoreo móvil resulta hoy una actividad difícil debido a los conflictos y a la pérdida de ganado, la identidad 'móvil' sigue estando muy presente y cobrando vigor gracias a la telefonía móvil, que permite especialmente mantener la 'riqueza' en gente y redes de sociabilidad.