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Extensão rural na TV um estudo da campanha de vacinação contra a febre aftosa no Globo Rural DiárioANDRADE NETO, Luís Boaventura de 14 August 2014 (has links)
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Previous issue date: 2014-08-14 / The proposal is to evaluate if the daily version of the thematic newscast Globo Rural (Grud) can function as a tool for Agricultural Extension. After a specific literature review, were recorded sixty-six (66) editions and analyzed fifteen reports shown about the campaign of vaccination against Foot-and-mouth disease, the subject of the reports chosen to be analyzed by this work. In addition, also sought to know who are and what thinks the people who goes to the cattle fair in Caruaru (dry region of Pernambuco), about Grud and how the thematic newscast in question assists they in daily work. Grud is shown in the open on national TV and appeared for the first time on October 9, 2000, from the program that is displayed by TV Globo on Sundays for more than thirty years. The reports address topics that interest the farmers and for those who deal directly or indirectly with the field. With the aid of work carried out by researchers as Paulo Freire, Juan Diaz Bordenave, Armand e Michelle Mattelart, Vera Íris Paternostro, and others, it is concluded that the Grud can be considered an important tool for the agricultural extension, and consequently, for the dissemination of scientific mass to your audience. / A proposta é avaliar se o telejornal temático Globo Rural Diário (Grud) pode funcionar como uma ferramenta para a Extensão Rural. Após a revisão bibliográfica, foi feita a gravação de sessenta e seis (66) edições e análise de quinze reportagens exibidas sobre a campanha de vacinação contra a febre aftosa, o assunto das matérias escolhido para ser analisados por este trabalho. Além disso, também procurou-se saber quem são e o que pensam os frequentadores da feira de gado de Caruaru (no Agreste de Pernambuco), sobre o Grud e de que forma o telejornal temático em questão os auxilia no trabalho diário. O Grud é exibido na TV aberta em rede nacional e surgiu no dia 09 de outubro de 2000, a partir do programa que é exibido aos domingos pela TV Globo há mais de trinta anos. As matérias abordam assuntos de interesse de produtores rurais e de quem lida direta ou indiretamente com o campo. Com o auxílio de trabalhos já realizados por pesquisadores como Paulo Freire, Juan Diaz Bordenave, Armand e Michelle Mattelart, Vera Íris Paternostro, entre outros, concluiu-se o que o Grud pode ser considerado uma ferramenta importante para a extensão rural e por consequência para a disseminação científica de massa para sua audiência.
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Atividade do interferon tipo I suíno na proteção contra o vírus da febre aftosa (FMDV) / Activity of swine type i interferon in protection against foot-and-mouth disease virus (FMDV)Botton, Sonia de Avila 08 March 2005 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this study is to evaluate the adjuvant effect of interferon alpha (IFNα) in swine vaccinated with a recombinant replication-defective adenovirus containing foot-and-mouth disease virus (FMDV) protein coding regions, as well as to understand the molecular mechanisms involved in the interaction of FMDV with its host. In the first part of this thesis, the adjuvant effect of pIFNα was evaluated in swine vaccinated with a recombinant vaccine delivered by a human adenovirus type 5 (Ad5) vector containing FMDV capsid (P1-2A) and 3Cpro proteinase coding regions (Ad5-A24). Swine were separated into 5 groups and inoculated with low (5x108 PFU) or high (5x109 PFU) doses of Ad5-A24 in the presence or absence of pIFNα (Ad5-pIFN, 109 PFU). Control animals received 6x109 PFU of an Ad5 vector containing the glycoprotein gene of vesicular stomatitis virus (Ad5-VSNJV-G). All swine were challenged at 42 days post vaccination (dpv) with FMDV-A24. Prior to challenge, blood samples were examined for IFN production, induction of IFN-induced genes (ISG s), FMDV-specific neutralizing antibodies and FMDV-specific antibody isotypes. After challenge, a number of parameters were analyzed including clinical score, viremia, lymphopenia and antibodies against FMDV structural (S) and non-structural (NS) proteins. The results indicate that both groups that received high-dose Ad5-A24 developed an FMDV-specific neutralizing antibody response by 14-21 dpv, which was maintained until the day of challenge. Both high-dose groups developed high levels of IgG1 and IgG2, however the IgG1 response was higher. The high-dose Ad5-A24 with IFN group developed higher levels of IgG1 than the group administered only high-dose Ad5-A24 and this difference was statistically significant. Antiviral activity and IFNα were detected in the groups that received IFN. The three ISG s examined, PKR, OAS and Mx1, were detected by real time RT-PCR in leukocytes from Ad5-pIFNα-vaccinated swine. After challenge, all animals in the control group developed early viremia, vesicular lesions, considerable lymphopenia and antibodies to FMDV NS proteins. The animals that received low-dose Ad5-A24 without IFN had similar clinical signs, except that fewer animals had viremia. In contrast, pigs inoculated with the low-dose Ad5-A24 and IFNα had a delayed onset of vesicular lesions and only one animal had detectable viremia. Animals vaccinated with high-dose Ad5-A24 without IFNα had no viremia, showed fewer lesions, one animal had no lesions, and delayed onset of disease compared to the low-dose Ad5-A24 groups. Four of five pigs vaccinated with high-dose Ad5-A24 and IFNα were completely protected from disease and only one animal in this group had a vesicular lesion restricted to the site of challenge virus inoculation. The results indicate that IFNα enhances the level of protection induced by the Ad5-FMD vaccine against homologous FMDV, supporting the use of IFNα as a potential adjuvant in FMD vaccination strategies. To investigate the effect of FMDV infection on the induction of the host IFN-α/β response, swine cells were infected with wild-type (WT) FMDV and a mutant FMDV lacking the L proteinase (Lpro) coding region (A12-LLV) at different multiplicities of infection. The synthesis of IFN-α and IFN-β mRNAs and three well characterized ISG s, PKR, OAS, and Mx1 mRNA, were evaluated by real time RT-PCR. A12-LLV infection resulted in significantly higher levels of induction of IFN-β mRNA as compared to WT virus infected cells, while IFN-α mRNA was not induced after either infection. The increased levels of IFN-β mRNA in A12-LLV-infected cells correlated with higher levels of induction of PKR, OAS and Mx1 mRNAs and antiviral activity. By using RNA interference (RNAi) technology to knock-down PKR mRNA expression, it was possible to demonstrate that the yield of A12-LLV was increased up to 200-fold, supporting the role of PKR as an inhibitor of FMDV replication. These results confirm that Lpro down regulates the innate immune response to FMDV infection at multiple levels. Previous studies indicated that control was at the translation initiation level by Lpro cleavage of translation initiation factor eIF-4G. The present data demonstrates that regulation also occurs at the level of transcription by inhibition of IFN-β mRNA induction through an unknown mechanism. / Esse trabalho tem como objetivo avaliar o efeito adjuvante do interferon alfa suíno em animais imunizados com uma vacina recombinante de um adenovírus defectivo contendo as regiões codificadoras das proteínas do FMDV, bem como investigar alguns dos aspectos moleculares envolvidos na interação FMDV e a célula hospedeira em uma espécie susceptível. Na primeira fase do trabalho, o efeito adjuvante do interferon alfa suíno (pIFNα) foi avaliado em suínos imunizados com uma vacina recombinante, tendo como vetor o adenovirus humano tipo 5 (Ad5), contendo regiões do capsídeo do FMDV A24 e da proteinase 3Cpro do FMDV A12 (Ad5-A24). Os suínos foram separados em 5 grupos e inoculados com baixa (5x108 PFU) e alta (5x109 PFU) dosagem de Ad5-A24 na presença ou na ausência de pIFNα (Ad5pIFNα, 109 PFU). O grupo controle foi inoculado com 6x109 PFU da glicoproteína do vírus da estomatite vesicular (VSV) cepa New Jersey (Ad5VSNJV-G). Todos os suínos foram desafiados aos 42 dias pós-vacinação (dpv) com FMDV-A24. Após a inoculação, as amostras de sangue foram examinadas para a produção de IFN, a indução de genes induzidos pelo IFN e os anticorpos neutralizantes e resposta de imunoglobulinas específicos para o FMDV. Depois do desafio um número de parâmetros foram analisados incluindo a avaliação clínica, viremia, linfopenia; além dos anticorpos contra as proteínas estruturais e não estruturais do FMDV. Os resultados obtidos indicam que ambos os grupos que receberam Ad5-A24 em alta dosagem desenvolveram níveis de anticorpos neutralizantes pelos 14-21 dpv, que foram mantidos até o dia do desafio. Os níveis de IgG1 foram maiores que de IgG2 nesses dois grupos, sendo que a IgG1 é considerada a mais relevante para conferir proteção ao FMDV. Dentre esses grupos, o que recebeu o IFN apresentou níveis significativamente mais altos desta imunoglobulina. Atividade antiviral e o IFNα foram detectados nos animais que receberam o IFN. A respeito da presença dos genes induzidos pelo IFN nos leucócitos dos suínos vacinados com Ad5-pIFNα, todos os três genes incluídos neste estudo, PKR, OAS e Mx1, foram detectados pelo real time RT-PCR. Após o desafio todos os animais do controle desenvolveram viremia, linfopenia, lesões vesiculares e os anticorpos contra as proteínas não estruturais do FMDV. Os animais que receberam baixa dose de Ad5-A24 sem IFN tiveram sinais clínicos similares, exceto que poucos animais desenvolveram viremia. Porém, os suínos inoculados com a mesma dose da vacina de Ad5-A24 com o IFN apresentaram as lesões vesiculares com início tardio e somente um animal teve detectável viremia. Os animais vacinados com a alta dose de Ad5-A24 sem IFN não tiveram nenhuma viremia e poucas lesões foram detectadas tardiamente após a inoculação do FMDV. Quatro dos cinco suínos, que receberam a alta dose da vacina com o IFN, foram protegidos da doença e somente um animal neste grupo teve uma lesão vesicular, restrita ao local do inoculação do vírus por ocasião do desafio. Esses resultados indicam que IFNα realça o nível da proteção induzido pela vacina do adenovírus-FMD contra o FMDV homólogo, suportando o uso do IFNα como um adjuvante potencial em estratégias de vacinação de FMD. Para avaliar os efeitos da infecção pelo vírus da FMD na indução da resposta de IFNα⁄β do hospedeiro, células de origem suína foram previamente infectadas em diferentes multiplicidades de infecção com o FMDV e com um vírus mutante que teve o gene que codifica a protease L ou Lpro deletado, o FMDLLV. A síntese de mRNA do IFNα e β bem como de três dos genes induzidos pelo IFN, PKR, OAS e Mx1 foram avaliados por real time RT-PCR. A infecção das células pelo FMDLLV induziu altos níveis de mRNA do IFNβ quando comparados com os do FMDV original. Contudo, não foi possível detectar os níveis de mRNA do IFNα na presença de ambos os vírus. O aumento nos níveis de mRNA do IFNβ foi relacionado ao aumento nos níveis de indução dos mRNAs de PKR, OAS e Mx1, assim como dos altos níveis de atividade antiviral. Pelo uso da tecnologia de interferência do RNA, usando siRNA (silencing RNA) para bloquear a expressão do mRNA da PKR, foi possível demonstrar que o título do FMDLLV aumentou cerca de 200 vezes. Desta forma foi possível confirmar o papel desta proteína como um inibidor da replicação do FMDV. Os resultados obtidos demonstram que a Lpro tem um importante papel na regulação da resposta imunológica inata do hospedeiro quando da infecção pelo FMDV em vários níveis. Estudos anteriormente realizados indicaram que o controle era efetuado ao nível da tradução pela clivagem do eIF4G. Os dados obtidos neste trabalho indicam que a regulação também ocorre ao nível da transcrição e pela inibição da indução do IFNβ através de um mecanismo ainda não conhecido.
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Avaliação dos resultados da Instrução Normativa nº 50/2008 (MAPA) na melhoria da purificação das vacinas contra a febre aftosa comercializadas no BrasilCosta, João Marcos Nacif da January 2018 (has links)
A febre aftosa é causada por um vírus do gênero Aphtovirus, cujas proteínas não estruturais (PNE) estão relacionadas diretamente a replicação viral e são comuns a todos os sorotipos e, portanto, são mais adequadas à pesquisa de anticorpos contra este vírus. Métodos de diagnóstico capazes de diferenciar animais infectados de vacinados aliados ao uso de vacinas purificadas quanto à PNE são imprescindíveis na estratégia para comprovação de ausência de transmissão viral. Através da Instrução Normativa nº 50/2008, o Brasil passou a realizar o controle oficial da pureza nas vacinas contra a febre aftosa. O objetivo deste trabalho foi avaliar se as chances de encontrar bovinos reativos aos testes sorológicos serão maiores antes da implantação do controle oficial, tanto nos resultados do controle oficial das vacinas, quanto nos inquéritos. Para isto, foram utilizados modelos de regressão logística com efeitos aleatórios, interações e controle de possíveis confundidores. Os resultados demonstraram que no realizado em laboratório oficial em 1016 partidas de vacinas, observou-se que a chance de ocorrência de resultados reativos antes da implantação da norma utilizando o método de triagem ELISA 3ABC NCPanaftosa foi 2,86 (IC95%,1,92-4,14) vezes a chance de ocorrência nos testes de vacina feitos após a norma, utilizando-se o mesmo método de triagem. Já a chance de resultados reativos antes da norma, utilizando-se o método NCPanaftosa, foi 19,70 (IC 95%,8,55- 45,37) vezes a chance de ocorrência após a norma com o uso do método PrioCHECK como triagem Já, a partir da comparação entre inquéritos soroepidemiológicos, foi possível observar que antes da implantação da IN50/2008 a chance de ocorrência de resultados reativos em bovinos que receberam uma dose de vacina foi 2,22 (IC 95%, 1,22-4,06) vezes a chance da ocorrência em bovinos não vacinados. Já, a chance de ocorrência de resultados reativos em bovinos que receberam duas ou três vacinas foi 5,94 (IC 95%, 3,25-10,87) vezes a de bovinos não vacinados. Nas estimativas modeladas para os inquéritos soroepidemiológicos realizados após a implantação da norma, independentemente do método de triagem utilizado, não houve associação significativa entre diferentes doses de vacinas e a ocorrência de animais reativos. Os resultados obtidos sugerem que há uma associação do controle oficial com a melhoria da produção de vacinas no que diz respeito a purificação do antígeno, assim como, indicam que a melhoria na pureza está associada à diminuição na chance de ocorrência de bovinos reativos em inquéritos soroepidemiológicos, ou seja, redução nos falso-positivos a campo. / Foot and mouth disease (FMD) is a highly contagious disease caused by an Aphtovirus. Non-structural proteins (NSP) of this virus are directly related to viral replication and are common to all serotypes. Therefore, are more suitable for antibodies-based serological diagnosis. Diagnostic methods capable of differentiating infected from vaccinated animals (DIVA) are important surveillance tools; however, strategies should be in step with the development of vaccines. Since January 2009, the Brazilian government has been conducting an official control to evaluate NSP purity in vaccines production through the Normative Instruction No. 50 from 2008. This paper evaluates the situation of the vaccines produced in Brazil regarding NSP purification based on the results of the official control carried out by MAPA, as well as the adequacy of the surveillance system based on seroepidemiological surveys. Logistic regression with random effects, interactions and control for potential confounders were the chosen models. For the data obtained from the control of vaccines carried out in the official laboratory, the model estimated that the chance of occurrence of seroreactive results before the application of the official control using the 3ABC NCPanaftosa ELISA as screening method was 2.86 (95% CI, 1.92-4.14) times the chance of occurrence in the vaccine tests made after the standard, using the same method. The chance of seroreactive results before the official control, using the NCPanaftosa method as screening, was 19.70 (95% CI, 8.55 to 45.37) times the chance of occurrence after the official control with the use of the PrioCHECK method Comparing the seroepidemiological surveys results, the model indicated that, before the official control of vaccine purity, the chance of occurrence of reactive results in cattle receiving a single dose of vaccine was 2.22 (95% CI, 1.22 -4.06) times the chance of occurrence in unvaccinated animals. Furthermore, the chance of occurrence of reactive results in animals receiving two or three vaccines was 5.94 (95% CI, 3.25-10.87) times that of unvaccinated animals. Despite that, there was no significant difference in the estimates of the odds ratio between different doses of vaccines regardless of the screening method used for the seroepidemiological surveys performed after the official control of vaccines purity,. The present study suggests that there is an association of the implementation of Normative Instruction No. 50 from 2008 with the improvement of the NSP purity of vaccines, as well as indicates that this improvement is associated with a decrease in chance of occurrence of reactive animals in seroepidemiological surveys, i.e., reduction of false-positives in field monitoring.
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State and local policy considerations for implementing the National Response PlanCline, John J. 03 1900 (has links)
CHDS State/Local / Approved for public release, distribution is unlimited / Threatened with the loss of federal funding for Homeland Security and emergency management preparedness programs, state and local entities must implement the National Response Plan and the National Incident Management System, which includes the Incident Command System, Unified Command, and the Multiagency Coordination System. Although mandated by Congress and implemented by Homeland Security Presidential Directive 5, underdeveloped areas of Indian country and small towns, especially farming and ranching communities and agriculturally-based counties are likely to find that they do not have the capacity to fully implement these mandated federal response programs. A theoretical terrorist-induced multistate Foot and Mouth Disease (FMD) outbreak is used to examine the impact of implementing newly established federally mandated response management programs on rural and tribal communities in agrarian states. Recovering from such an agroterrorism bioattack would require a coordinated multi-disciplinary response that is heavily dependent on local, tribal, state, and private sector personnel. However, because the United States has not experienced an outbreak of FMD since 1929, many of the skills required to quickly diagnose and respond may no longer exist. This thesis identifies potential methods for obtaining and deploying the FMD virus in a coordinated bioattack on the U.S. economy. / Director, Idaho Bureau of Disaster Services
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Logistické zabezpečení zásahu při výskytu slintavky a kulhavky ve velkochovu s 300 kusy skotu / Logistics, security and intervention, a strategic approach to the occurrence of foot-and-mouth disease on 300 livestock in a farming communityŘEZNÍČKOVÁ, Martina January 2008 (has links)
The foot and mouth disease is an acute, very contagious virus disease of even-toed ungulates (cattle, Wheel, pigs). The primary source of the infection is an ill animal, a secondary source are all the subject contaminated by the originator of the illness. Also people often pass the illness (on their shoes and also clothes). At present, the foot and mouth disease in Great Britain is mentioned at most; however, the epi-centers of the contagion of this illness may be found in many other places all around the world. Although the last occurrence of the foot and mouth disease was recorded in 1975 in the Czech Republic, the real risk of spreading this infection in our territory exists also at present. The people get infected with foot and mouth disease may very seldom. Also the most animals are able to survive this disease; in spite of this fact, spreading the infection in the breeding causes immense economic loss. For this reason, many countries consider necessary to fight against the infection by all the possible means. First of all the prevention and preparation of various plans and preparation of experts is accentuated. In case of any suspicion concerning the foot and mouth disease it is necessary to take the necessary measures. Only thanks to a thorough preparation and correct observation of all the measures it is possible to fight effectively with this dangerous infection, although at the expense of lives of many animals.
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Modelos de EDP integrados a logica Fuzzy e metodos probabilisticos no tratamento de incertezas : uma aplicação a febre aftosa em bovinos / PDE models associated to fuzzy logic ans statistical methods in the treatment of uncertainties : an application on food-and-mooth diseaseMissio, Maristela 19 September 2008 (has links)
Orientador: Laercio Carvalho de Barros. / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica. / Made available in DSpace on 2018-08-12T00:22:47Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: A febre aftosa é uma patologia viral, infecto-contagiosa, caracterizada por um cenário repleto de incertezas que lhe são inerentes, resultantes da influência de fatores socioeconômicos e ambientais relacionados ao processo de transmissão, que pode ocorrer por via direta e indireta. Em epidemiologia, grande parte das incertezas são tratadas ou pela Teoria das Probabilidades ou pela Teoria de Conjuntos Fuzzy, a depender da natureza, seja ela oriunda da aleatoriedade ou de verdade parcial. O uso integrado de modelos clássicos, particularmente as Equações Diferenciais Parciais (EDP), modelos fuzzy e probabilísticos no tratamento das duas classes de incertezas ainda é muito incipiente. Com a intenção de contribuir para o aumento dos estudos nessa área, propõe-se um modelo integrado, envolvendo EDP, lógica fuzzy e métodos probabilísticos, a fim de estudar a dinâmica espacial e temporal de fenômenos epidemiológicos, cujas incertezas são importantes para sua evolução. Para tanto, tomou-se como objeto de estudo a febre aftosa em bovinos e elaborou-se um modelo SIR envolvendo EDP para estudar sua evolução espaço-temporal com parâmetros de difusão e transmissão incertos. Esses foram estimados fazendo-se uso de Sistemas Baseados em Regras Fuzzy (SBRF). As variáveis lingüísticas utilizadas nos SBRF apresentaram incertezas de natureza aleatória, as quais foram tratadas por modelos estocásticos. Na implementação computacional, fez-se o acoplamento dos métodos de elementos finitos para a discretização espacial, e Cranck-Nicolson para a temporal, toolbox fuzzy para os modelos fuzzy e Monte Carlo para os modelos estocásticos, todos em um mesmo algoritmo, construído nos ambientes Matlab e Fortran. / Abstract: The foot-and-mouth disease is a viral, infectum contagious pathology, characterized for a scene full of inherent uncertainties, resultants of the influence of social, economic and environmental factors related to the transmission process, that can occur for direct and indirect means. In Epidemiology, great part of the uncertainties are treated either by the Theory of Probabilities or by Fuzzy Logic Theory, depending on the nature, in accordance with the type of uncertainty which can be either deriving of the randomness or coming from the subjectivity. The integrated use of models involving Partial Differential Equations (PDE), Fuzzy Theory and Probabilistic in the treatment of the two categories of uncertainties, simultaneously, is still very incipient. Aiming to contribute to the growth of existing studies in this area, we propose an integrated model, involving PDE Models, Fuzzy Models and Stochastic Models, in order to study the space and secular dynamics of these epidemiological phenomena, whose uncertainties are important for their evolution. To do so, the foot-and-mouth disease in bovines was taken overcome as our study's object and we elaborated a SIR model involving EDP to study its space-weather evolution with uncertain parameters of diffusion and transmission. Due the uncertainties these parameters had been estimated using Rule-Based Fuzzy Systems (RBFS). The linguistic variables of the RBFSs presented uncertainties of random nature, which were treated by random models. For computational results, we coupling several models, using the method of finite elements for the space discretization and Cranck-Nicolson for time discretization, toolbox fuzzy for Fuzzy Models and Mount Carlo for Random Models, all in the same algorithm constructed in the environments Matlab and Fortran. / Doutorado / Matematica Aplicada / Doutor em Matemática Aplicada
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Epidémiologie moléculaire et évolution de l'entérovirus A71 et interactions génétiques avec les autres entérovirus de l'espèce A responsables de la maladie pied-main-bouche. / Molecular epidemiology and evolution of enterovirus A71 and genetic interactions with others enterovirus A species responsive of Hand-Foot and Mouth DiseaseHassel, Chervin 21 April 2015 (has links)
La maladie pied-main-bouche (PMB) et l’herpangine sont deux maladies pédiatriques bénignes causées par les entérovirus (EV), en particulier les sérotypes de l’espèce A (EV-A). Le sérotype EV-A71 fait l’objet d’une surveillance dans les pays du Sud Est de l’Asie car il est associé à des atteintes neurologiques sévères chez les très jeunes enfants, parfois mortelles (défaillance cardio-pulmonaire). Les infections causées par les autres EV-A tel que le coxsackievirus A16 (CV-A16) provoquent rarement des atteintes sévères. En Europe, les cas de maladie PMB causés par l’EV-A71 ne font pas l’objet d’une déclaration obligatoire, car ce virus ne cause pas d’épidémies de grande ampleur. L’objectif général de la thèse était d’étudier l’épidémiologie des EV-A en Europe et nous avons utilisé une approche phylogénétique bayésienne pour analyser un échantillon de 500 souches. Nous montrons la circulation discontinue de l’EV-A71 de deux populations virales principales (sous génogroupes C1 et C2), ce qui explique la rareté des épidémies en Europe. L’épidémiologie de ce virus est aussi caractérisée par des transports de souches entre les pays Européens et sporadiquement entre l’Europe et l’Asie (sous génogroupes B5 et C4). La recombinaison génétique intertypique survient rarement parmi les populations d’EV-A71 en circulation et ne contribue pas significativement à leur diversité génétique. Cependant, ce mécanisme génétique est relié à l’émergence d’un sous génogroupe CV-A16 qui circule en France depuis 2011. Comparés à l’EV-A71, les sérotypes CV-A2, CV-A4, CV-A6 sont plus fréquemment sujets à des événements de recombinaison intertypiques. L’analyse de la sélection à l’échelle moléculaire indique que la fixation des mutations dans les protéines de capside de l’EV-A71 est lente, probablement à cause des contraintes structurales et fonctionnelles. La surveillance des infections à EV-A71 en Europe devrait être renforcée à cause de la neurovirulence de ce virus, de l’introduction récente et répétée de souches variantes « asiatiques » et de l’existence d’une grande diversité de génogroupes en Afrique et en Inde encore peu explorée. / Hand-Foot and Mouth Disease (HFMD) and Herpangina are two benign pediatric diseases caused by Enteroviruses (EV), especially enterovirus A species serotypes (EV-A). Infections caused by the EV-A71 serotype are monitored in countries of South East Asia because they are associated with severe neurological symptoms in young children and may be fatal (cardiopulmonary failure). Infections caused by the other EV-A serotypes, e.g. coxsackievirus A16 (CV-A16), rarely induce severe symptoms. In Europe, EV-A71 HFMD cases are not notifiable because this virus does not cause large-scale epidemics. The overall objective of this thesis was to study the EV-A epidemiology in Europe and we used a Bayesian phylogenetic approach to analyze 500 viral strains. We show a discontinued circulation of two EV-A71 populations (C1 and C2 subgenogroups), which explains the rare outbreaks in Europe. The epidemiology of this virus is characterized by transportation events of viral strains between European countries and sporadically between Europe and Asia (C4 and B5 subgenogroups). Intertypic genetic recombination occur rarely among circulating EV-A71 populations and does not contribute significantly to their genetic diversity. We found that genetic mechanism was related to the emergence of a new CV-A16 subgenogroup, which is circulating in France since 2011. In comparison with EV-A71, a number of serotypes (CV-A2, CV-A4, and CV-A6) are more frequently involved in intertypic recombination events. The structural and functional constraints are possible factors involved in the slow mutation fixation in the EV-A71 capsid proteins as determined by analyses of molecular selection. Neurovirulence, the recent and repeated introductions of variants “Asian” strains, and the diversity of genogroups in Africa and India call for strengthened surveillance of EV-A71 infections among European countries.
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