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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Contribuição para o estudo da dinâmica de populações de cães e gatos do município de Jaboticabal, São Paulo

Nunes, Juliana Olivencia Ramalho [UNESP] 23 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-23Bitstream added on 2014-06-13T18:55:50Z : No. of bitstreams: 1 nunes_jor_me_jabo.pdf: 1573295 bytes, checksum: 55a5cc5a8fd3d59d09557d2948d6bd19 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O convívio do ser humano com cães e gatos tem se intensificado sem a devida adoção de posturas de posse responsável. O presente trabalho teve propósito de contribuir com os estudos da dinâmica populacional de cães e gatos em Jaboticabal, São Paulo, e avaliar o nível de conhecimento das pessoas sobre posse responsável e zoonoses. A obtenção de dados foi feita em dois bairros da periferia, nos anos 2005 e 2010, por meio de questionários. No Bairro Residencial entrevistaram-se 228 moradores em 2005 e, em 2010, foram re-entrevistados 196. No Bairro Jardim Boa Vista foram 111 em 2005, e 84 em 2010. Foram realizados a Análise de Correspondência Múltipla e o Geoprocessamento. Obteve-se um alto número de animais com livre acesso às ruas, na maioria machos e principalmente gatos. Esses animais podem ser computados como semi-restritos ou de vizinhança, com possibilidade de causar transtornos. Além de já estarem em número elevado, os animais de rua têm respaldo da comunidade, que os alimenta, dando condições para que perpetuem. Existe um programa de castração no Município, mas a população de cães e gatos continua crescendo, pois o número de animais castrados ainda é pouco expressivo. Do ano de 2005 para 2010, houve aumento significativo da quantidade de cães idosos, principalmente fêmeas; isso pode ser reflexo da postura das pessoas de maiores cuidados com os animais. As informações obtidas em muito contribuirão para que seja estabelecida a dinâmica da população de cães e gatos em todo Município de Jaboticabal. Certamente, isto dará um suporte valioso ao Serviço Municipal de Saúde para o planejamento e a adoção de medidas mais adequadas de controle de populações animais e de zoonoses / The interaction of humans with dogs and cats has increased without proper postures of responsible ownership. The purpose of this study was to contribute to studies of population dynamics of dogs and cats in Jaboticabal, São Paulo, and assess the level of knowledge of the community about responsible ownership and zoonoses. The data collection was done with two neighborhoods, in the years 2005 and 2010, using questionnaires. In the Neighborhood Residential 228 residents were interviewed in 2005 and 196 residents were re-interviewed in 2010. In Jardim Boa Vista 111 residents were interviewed in 2005 and 84 in 2010. We performed a Multiple Correspondence Analysis and GIS. We obtained a high number of animals witch has free access to the streets, mostly male and cats. These animals could be classified as semi-restricted or neighborhood, with the possibility of causing trouble. In addition, besides the high number of animals, the street animals have the support of the community that provide food to them, giving conditions to perpetuate. There is a castration program in the city, but the cats and dogs population continues to grow due to the fact that the number of castrated animals is still small. From 2005 to 2010, there was a significant increase in the number of older dogs, especially female; this may reflect the attitude of the community to be more careful with animals. The information obtained will contribute greatly to the setting of a dynamic population of dogs and cats throughout Jaboticabal. Certainly, it will provide valuable support to the Municipal Health Service for planning and adoption of suitable measures to control animal populations and zoonoses
132

Contribuição para o estudo da dinâmica de populações de cães e gatos do município de Jaboticabal, São Paulo /

Nunes, Juliana Olivencia Ramalho. January 2011 (has links)
Resumo: O convívio do ser humano com cães e gatos tem se intensificado sem a devida adoção de posturas de posse responsável. O presente trabalho teve propósito de contribuir com os estudos da dinâmica populacional de cães e gatos em Jaboticabal, São Paulo, e avaliar o nível de conhecimento das pessoas sobre posse responsável e zoonoses. A obtenção de dados foi feita em dois bairros da periferia, nos anos 2005 e 2010, por meio de questionários. No Bairro Residencial entrevistaram-se 228 moradores em 2005 e, em 2010, foram re-entrevistados 196. No Bairro Jardim Boa Vista foram 111 em 2005, e 84 em 2010. Foram realizados a Análise de Correspondência Múltipla e o Geoprocessamento. Obteve-se um alto número de animais com livre acesso às ruas, na maioria machos e principalmente gatos. Esses animais podem ser computados como semi-restritos ou de vizinhança, com possibilidade de causar transtornos. Além de já estarem em número elevado, os animais de rua têm respaldo da comunidade, que os alimenta, dando condições para que perpetuem. Existe um programa de castração no Município, mas a população de cães e gatos continua crescendo, pois o número de animais castrados ainda é pouco expressivo. Do ano de 2005 para 2010, houve aumento significativo da quantidade de cães idosos, principalmente fêmeas; isso pode ser reflexo da postura das pessoas de maiores cuidados com os animais. As informações obtidas em muito contribuirão para que seja estabelecida a dinâmica da população de cães e gatos em todo Município de Jaboticabal. Certamente, isto dará um suporte valioso ao Serviço Municipal de Saúde para o planejamento e a adoção de medidas mais adequadas de controle de populações animais e de zoonoses / Abstract: The interaction of humans with dogs and cats has increased without proper postures of responsible ownership. The purpose of this study was to contribute to studies of population dynamics of dogs and cats in Jaboticabal, São Paulo, and assess the level of knowledge of the community about responsible ownership and zoonoses. The data collection was done with two neighborhoods, in the years 2005 and 2010, using questionnaires. In the Neighborhood Residential 228 residents were interviewed in 2005 and 196 residents were re-interviewed in 2010. In Jardim Boa Vista 111 residents were interviewed in 2005 and 84 in 2010. We performed a Multiple Correspondence Analysis and GIS. We obtained a high number of animals witch has free access to the streets, mostly male and cats. These animals could be classified as semi-restricted or neighborhood, with the possibility of causing trouble. In addition, besides the high number of animals, the street animals have the support of the community that provide food to them, giving conditions to perpetuate. There is a castration program in the city, but the cats and dogs population continues to grow due to the fact that the number of castrated animals is still small. From 2005 to 2010, there was a significant increase in the number of older dogs, especially female; this may reflect the attitude of the community to be more careful with animals. The information obtained will contribute greatly to the setting of a dynamic population of dogs and cats throughout Jaboticabal. Certainly, it will provide valuable support to the Municipal Health Service for planning and adoption of suitable measures to control animal populations and zoonoses / Orientador: Adolorata Aparecida Bianco Carvalho / Coorientador: Antonio Sergio Ferraudo / Banca: Angela Cleusa de Fátima Banzatto de Carvalho / Banca: Maria Angélica Dias / Mestre
133

Análise quali-quantitativa sobre a percepção da transmissão de zoonoses em Vargem Grande, São Paulo (SP): a importância dos animais de companhia, da alimentação e do ambiente / A quali-quantitavive analysis on the zoonosis transmition perception in Vargem Grande, São Paulo (SP): the importance of pets, food and environment

Carolina Ballarini Zetun 07 August 2009 (has links)
O presente trabalho aborda a questão de transmissão de zoonoses de forma muito mais ampla do que ela costuma ser tratada. Com o uso de análises quali-quantitativas, buscou-se entender o que as pessoas pensam e como elas se comportam, quanto à relação delas com o ambiente, com os animais de estimação e com os alimentos que elas ingerem, a partir de uma contextualização local, de acordo com suas condições sócio-econômicas e culturais. Vargem Grande é um bairro pobre e sem infra-estrutura adequada, não possui calçamento das ruas, o esgoto é a céu aberto, há presença de lixo nas vias públicas e nos terrenos baldios, e grande população de roedores. A população do bairro possui hábitos insalubres como, andar descalços pelas ruas, jogarem lixo e acumularem entulho em seus próprios quintais e fazerem suas hortas ao lado do esgoto. A técnica do Discurso do Sujeito Coletivo possibilitou a construção de uma análise aprofundada, que permitiu identificar categorias, que revelam a percepção da população quanto a sua relação com os animais, os alimentos de origem animal e o ambiente em que vivem. A partir do perfil do bairro e dos moradores, bem como das categorias, que revelam suas representações sociais, foi possível fornecer bases para futuras medidas de controle e prevenção de zoonoses e para um Programa de Educação em Saúde. Concluiu-se que só ocorrerá melhoria da qualidade de vida da população de estudo, se esse for um objetivo comum entre os órgãos públicos e empresas de distribuição de água e esgoto, os próprios habitantes do bairro, e os profissionais de saúde, incluindo veterinários. / The present work aimed to illustrate the transmission of zoonosis in a more complete way than it is usually treated. Using quali-quantitative analysis to understand what people think and how they behave, how they relate with the environment, with companion animals and the food that they eat, a local context was defined according to their social economic and cultural conditions. Vargem Grande is a poor neighborhood without adequate infrastructure, paved streets, sewer system, there is trash on public ways and in vacant lots and large populations of rodents. The population of the district has unhealthy habits such as walking barefoot, throw garbage and debris in their own backyards and make their gardens next to the sewer. The technique Collective Subject Speech enabled the construction of a detailed analysis, identified categories that show the peoples perception about their relation with animals, food and the environment in which they live. From the neighborhood and residents profile, such as the categories that show their social representations, we provided groundwork for future measures for prevention and control of zoonosis and a program of education in health. We concluded that an improvement on life quality will only occur if a common goal between government, companies of water supply and sewage, the population and health professionals, including veterinarians.
134

Avaliação sanitária de animais silvestres de produção abatidos em abatedouro / Sanitary evaluation of commercially produced wild animals slaughtered in abattoir

Ricardo Pinho Gomez Lopez 05 February 2010 (has links)
Muitas espécies de mamíferos selvagens são criadas para produção de carne. No Brasil, a capivara (Hydrochaeris hydrochaeris), a paca (Agouti paca), o cateto (Tayassu tajacu) e a queixada (Tayassu pecari) são criadas comercialmente para este fim, porém são escassas as informações sanitárias a respeito dessas espécies. Assim, o presente estudo teve por objetivo estudar a presença de infecção causada por leptospiras, micobactérias, brucelas e Erysipelothrix spp. em 138 animais dessas quatro espécies, provenientes de nove criadouros e abatidos em estabelecimento com Serviço de Inspeção Federal. Nenhum animal apresentou anticorpos séricos contra brucelas lisas. As capivaras apresentaram a maior freqüência de animais sorologicamente reagentes para leptospiras (54,5%), seguidas das queixadas (39%) e dos catetos (21,7%). O sorovar mais provável mais freqüente para as espécies estudadas foi o Grippotyphosa, seguido do Hardjobovis e do Tarassovi. Das capivaras foram isolados Leptospira santarosai a partir de rim e Mycobacterium xenopi a partir de linfonodo mesentérico. Das queixadas foi isolado Erysipelothrix rhusiopathiae a partir de tonsila. Segundo os bancos de dados Scopus, Pubmed e Cab Abstracts (Ovid), trata-se dos primeiros relatos de isolamento de M. xenopi em capivara e de E. rhusiopathiae em queixada. / Many species of wild mammals are raised for meat production. In Brazil, the capybara (Hydrochaeris hydrochaeris), paca (Agouti paca), collared peccary (Tayassu tajacu) and the white-lipped peccary (Tayassu pecari) are commercially bred, however there is limited sanitary information related to these species. This study aimed to search for the presence of infection caused by Leptospira spp., Mycobacteria spp., Brucella spp. and Erysipelothrix spp. in 138 animals belonging to those species, coming from nine commercial breeders and slaughtered under the Federal Inspection Service. None of these animals presented antibodies against smooth brucellas. The capybaras showed the highest frequency of seropositive animals for leptospirosis (54.4%), followed by the white-lipped peccaries (39%) and the collared peccaries (21.7%). The most frequent serovar was Grippotyphosa, followed by Hardjobovis and Tarassovi. Leptospira santarosai was isolated from the kidneys and Mycobacterium xenopi from the mesenteric lymph nodes of the examined capybaras. Erysipelothrix rhusiopathiae was isolated from the tonsils of one white-lipped peccary. According to the data banks Scopus, Pubmed e Cab Abstracts (Ovid), this is the first report of M. xenopi isolation from capybara and of E. rhusiopathiae from white-lipped peccary.
135

Conhecimentos e percepção sobre esporotricose em região endêmica: Pelotas, RS, Brasil / Knowledge and perception of sporotrichosis in an endemic region: Pelotas, Brazil

Silva, Franklin de Moraes Vaz da 28 February 2014 (has links)
Made available in DSpace on 2014-08-20T14:37:54Z (GMT). No. of bitstreams: 1 dissertacao_franklin_de_moraes_vaz_da_silva.pdf: 964493 bytes, checksum: 4984372f2eaf08c502de40b75e4a01fb (MD5) Previous issue date: 2014-02-28 / Sporotrichosis is a subcutaneous mycosis with worldwide distribution, caused by the fungal species Sporothrix schenckii complex, its endemic in areas with temperatures between 25-28ºC. Cause a chronic infection in humans, with significant economic and social impact, causing direct and indirect losses in population. To study the knowledge of the population in endemic areas, a cross-sectional, population-based between December, 2013 and February, 2014 was conducted in the city of Pelotas - RS, using a structured questionnaire divided into three sections. In the first section, global data such as age , sex, occupation, education, the second section data on the relationship between respondents with pets, and the third section on knowledge and perceptions were collected interviewed about definitions and concepts about mycosis, zoonosis and knowledge of sporotrichosis. 618 interviews, being composed of 40.94% (253/618) men and 59.06% (365/618) of women were conducted. 73.62% (455/618) are owners of pets. Of these, 50.32% (229/455) kept their animals out of home with 21.53% (49/229) of these are cats. In the population that does not have pets, the cat was the species with greater contact between 19.02% (31/163) respondents. Students achieved the best performance on questions about knowledge of ringworm and zoonosis. On knowledge of sporotrichosis least half of the students 44.17% (273/618) and 26.51% (164/618) of health professionals were aware, all other categories were below 5% accuracy. Although the city of Pelotas - RS, is considered an endemic area for sporotrichosis, we found a low level of knowledge about sporotrichosis by population, for this, greater awareness and information about the disease is necessary. / A esporotricose é uma micose subcutânea zoonótica de distribuição mundial, causada por espécies fúngicas do complexo Sporothrix schenckii, endêmica em áreas com temperatura entre 25 a 28ºC. Causa infecção crônica em humanos, com grande impacto econômico e social, provocando perdas diretas e indiretas na população. Para estudar o conhecimento da população em área endêmica, foi realizado um estudo transversal, de base populacional entre dezembro de 2013 e fevereiro de 2014, na cidade de Pelotas RS, utilizando questionário estruturado dividido em três seções. Na primeira seção foram coletados dados globais como idade, sexo, ocupação, escolaridade, a segunda seção foram coletados dados referentes à relação entre os entrevistados com animais domésticos, e a terceira seção referente ao conhecimento e percepção dos entrevistados sobre definições e conceitos sobre micose, zoonose e conhecimento sobre esporotricose. Foram realizadas 618 entrevistas, sendo compostas por 40,94% (253/618) de homens e 59,06% (365/618) de mulheres. 73,62% (455/618) são proprietários de animais de estimação. Destes, 50,32% (229/455) mantinham seus animais em regime semidomiciliado, sendo destes 21,53% (49/229) de gatos. Na população que não possui animais de estimação, o gato foi a espécie com maior contato 19,02% (31/163) entre os entrevistados. Os estudantes obtiveram o melhor desempenho nas questões sobre conhecimento de micose e zoonose. Sobre o conhecimento da esporotricose menos da metade dos estudantes 44,17% (273/618) e dos profissionais da saúde 26,51% (164/618) tinham conhecimento, todas as demais categorias ficaram abaixo dos 5% de acertos. Embora, a cidade de Pelotas RS, seja considerada uma região endêmica para esporotricose, encontramos um baixo índice de conhecimento sobre esporotricose pela população, sendo necessária uma maior divulgação e informação sobre a doença.
136

Etude des mécanismes de haute pathogénicité des Henipavirus / Study on mecanisms of high pathogenicity of Henipaviruses

Dhondt, Kévin 21 November 2014 (has links)
Les Henipavirus sont des paramyxovirus zoonotiques émergents hautement pathogènes. Ils sont capables d’infecter un large spectre d’hôtes incluant notamment la chauve-souris frugivore (réservoir naturel), le porc et l’homme. Etant donné leur très grande dangerosité et en l’absence de traitements curatifs ou prophylactiques efficaces, ces virus doivent être manipulés dans un laboratoire de classe P4. Dans une première partie, nous étudions l’effet de composés glyco-amino-glycanes sur l’infection par les Henipavirus ainsi que leur potentielle application en tant que traitement. Dans une seconde partie, nous nous attachons à comprendre les interactions entre le système immunitaire de l’hôte et le virus. Afin de mieux comprendre ces interactions, nous avons utilisé une approche basée sur l’utilisation de souris déficientes pour certaines voies de l’immunité. En effet, bien que les récepteurs cellulaires au virus (EFN B2 et B3) soient fonctionnels chez la souris, celle-ci est résistante à l’infection par voie intrapéritonéale. Nous avons analysé la susceptibilité au virus Nipah (NiV) de souris privées de différentes voies du système immunitaire inné et adaptatif. Les résultats obtenus permettent d’envisager certaines lignées de ces souris comme nouveaux modèles animaux pour l’étude de l’immunopathogénèse du NiV. Cette étude suggère aussi que le système interféron de type I joue un rôle crucial dans la limitation de la propagation virale vers le cerveau et que les lymphocytes T sont nécessaires à la complète élimination du virus. Les macrophages jouent, quant à eux, un rôle central et indispensable, à l’interface entre système inné et adaptatif. Enfin, nous abordons les prémices d’un projet visant à identifier les différences d’interactions au niveau moléculaire entre les protéines non-structurales du virus et les protéines du système immunitaire inné chez l’Homme et la souris afin de voir s’il se dégage des différences d’interactions pouvant expliquer les différences de pathogénie. Ces travaux ont donc permis d’identifier de nouveaux modèles animaux et de mieux caractériser les interactions entre le pathogène et le système immunitaire de l’hôte, de l’échelle moléculaire à l’échelle de l’organisme entier. Néanmoins, les mécanismes précis de ces interactions restent à élucider et permettront certainement de mieux comprendre la grande diversité de pathogénie des Henipavirus. / Henipaviruses are highly pathogenic emerging zoonotic paramyxoviruses. They can infect a broad spectrum of mammals including flying foxes (Pteropus fruit bats), its reservoir, pigs and humans. As there are neither therapeutic drugs nor efficient prophylactic treatment towards these highly lethal viruses, they have to be manipulated in biosafety level-4 laboratories. In the first part of this thesis, we study the role of glyco-amino-glycans on Henipavirus infection and their potential use as treatment. In the second part, we describe the interaction between the host immune system and the pathogen. To investigate these interactions, we took advantage of different transgenic mouse models deficient for some immune pathways. Indeed, although mice possess the viral entry receptor for Henipaviruses, they do not succumbed to intraperitoneal infection. We analyzed the susceptibility to Nipah virus (NiV) infection of mice deleted for different components of innate and adaptive immune systems. Obtained results showed that some of these mice can be used as new models for NiV immunopathogenesis study. This study also suggests that type I interferon system plays a major role in limitation of viral spreading to the brain and that T cells are necessary for full viral clearance. Macrophages act at the crossroad of immunity, between innate and adaptive system. Finally, we deal with the preliminary phases of a project which aims to identify the differences, at a molecular level, of interaction between non-structural viral proteins and innate immunity proteins in mice and human. Such differences could explain the different clinical patterns that are observed in these species. In conclusion, this thesis allowed to identify new animal models and to better characterize host-pathogen interactions, from molecular to whole organism level. However, the precise mecanisms of these interactions remain to be elucidated and would probably help to understand the great diversity of pathogeny of Henipaviruses.
137

Identification et caractérisation moléculaires des rétrovirus simiens et évaluation du risque de transmission à l'homme en Afrique Centrale / Identification and molecular characterization of simian retroviruses and assessment of human transmission risk in Central Africa

Ahuka Mundeke, Steve 24 November 2011 (has links)
De nombreux primates d'Afrique sont infectés par les SIV et SLTV en particulier par ceux reconnus comme les ancêtres du VIH et HTLV à l'origine de graves épidémies chez l'homme. Des humains en Afrique continuent d'être exposés à ces virus lors des activités liées à la chasse. Ainsi le risque de transmissions inter-espèces des rétrovirus des primates aux humains persiste toujours dans cette région. Nous avons montré que le mangabey agile est infecté par un SIVagi phylogénétiquement très proche du SIVrcm infectant le mangabey à collier blanc au Cameroun. Nous avons montré aussi que les SIVdeb infectant les cercopithèques de Brazza se regroupent phylogénétiquement selon leurs régions géographiques d'origine non seulement à travers l'Afrique Equatoriale mais aussi à l'intérieur même du Cameroun. Nous avons adapté et validé un outil sérologique (Luminex) qui permet de tester près de 34 antigènes SIV/HIV simultanément. Cet outil et d'autres nous ont permis ensuite de documenter une prévalence globale élevée d'infection SIV et STLV chez les singes chassés pour la viande de brousse en RDC, particulièrement chez les espèces les plus consommées. De nouvelles lignées de SIV et STLV ont aussi été décrites. Par ailleurs, nous avons montré pour la première fois que les fécès peuvent être utilisés pour la détection des STLV chez les bonobos qui sont naturellemnt infectés par les STLV-2 et 3. En revanche, aucune évidence d'infection SIV chez les bonobos n'a été observée. Les travaux de cette thèse contribuent à l'amélioration des connaissances sur les infections rétrovirales chez les primates non humains au Cameroun et en RDC, complètent les informations disponibles sur les réservoirs du VIH-1 et HTLV et enfin fournissent des éléments d'appréciation du risque de transmission de ces virus à l'homme en RDC et au Cameroun. / SIVs and SLTVs infecting apes and monkeys in Africa are the progenitors of HIV and HTLV. Numerous African non-human primates are infected with SIV and STLV and humans continue to be exposed to these viruses by hunting and handling of primate bushmeat. Therefore the risk of cross-species transmissions from primates to humans is still persistent. We showed that SIVagi infecting captive agile mangabey is most closely related to SIVrcm from a wild-caught red capped mangabey from Cameroon. We observed also phylogeographic clustering among SIVdeb strains from Cameroon, DRC and Uganda, but also among distinct areas in Cameroon. We adapted and evaluated a novel high troughput immune assay that included 34 different HIV and SIV antigens in a single well. Using this tool and others, we found a high SIV and STLV prevalence especially among the most hunted monkeys in DRC. We identified also new SIV and STLV lineages. On the other hand, we did not find any evidence of SIV infection in bonobos. However, we showed, for the first time, that fecal samples could be used to detect STLV infection in bonobos that are naturally infected with STLV-2 and 3. The results obtained during this thesis contribute to the improvement of our knowledge on retroviral infections in nonhuman primates from Central Africa, complete information on HIV and HTLV reservoirs and provide background information on human transmission risk of these infections in central Africa especially in DRC.
138

Caractéristiques virologiques et pathogéniques du virus H5N1 et son rôle à l'interface hôte-environnement / Virological and pathogenic characteristics of the H5N1 virus and its role at the host-environment interface

Gutierrez, Ramona 05 December 2011 (has links)
Le virus de l'influenza aviaire hautement pathogène (IAHP) de sous-type H5N1 a causé de nombreuses pertes humaines, animales et économiques à travers le monde, notamment en Asie du Sud-Est. Son potentiel pandémique est une source d'inquiétude majeure en santé publique. Au Cambodge, l'infection est enzootique, et a causé la mort de 16 personnes depuis sa première détection en 2004 dans le pays, dont 8 pour la seule année 2011. Bien que l'hypothèse de la transmission directe hôte-hôte (animal-animal ou animal-homme) soit privilégiée, de récentes études semblent clairement incriminer certains éléments constitutifs de l'environnement dans le cycle de transmission du virus. Cependant, peu de données sont actuellement disponibles sur le sujet. Le travail de cette thèse a consisté en grande partie à apporter quelques réponses aux nombreuses questions soulevées. Des méthodes de détection du virus H5N1 dans l'environnement ont été mises au point, validées, et utilisées pour la détection de virus dans des prélèvements environnementaux collectés sur des sites d'épizooties au Cambodge. Le rôle de passereaux, capturés pour la réalisation de certains rituels bouddhistes en Asie, dans la dissémination du virus aux populations aviaires et humaines, a également été étudié. En parallèle, des données importantes du mode d'évolution du virus H5N1 au sein d'hôtes aviaires, jusqu'alors inexistantes, ont été apportées par l'étude des quasi-espèces du virus. L'ensemble des résultats rassemblés dans cette thèse souligne l'importance du rôle de l'environnement dans la dissémination et la transmission du virus IAHP H5N1. / The Highly Pathogenic Avian Influenza (HPAI) virus, subtype H5N1, has caused important human, animal and economical and losses in all countries affected, especially in Southeast Asia. Its pandemic potential is a major public health concern. In Cambodia, the infection is enzootic, and has caused 16 human fatalities since its first detection in the country in 2004, out of which 8 occurred in 2011. Although the hypothesis of direct host-to-host (animal-to-animal or animal-to-human) transmission is commonly accepted, recent studies clearly identified some environmental components as sources for avian and/or human contamination with H5N1 virus. Nonetheless, only few data are currently available on this topic. The work presented in this thesis aimed at better describing the role of the environment in the transmission cycle of the H5N1 virus. H5N1 virus detection methods in the environment were designed, validated and used for the detection of virus in environmental samples collected during epizootic outbreaks in Cambodia. The role of the Merit Release Birds, used during some common Buddhist rituals in Asia, in the dissemination of the virus to avian and human populations was also studied. In parallel, important and novel data regarding the evolution of the H5N1 virus within avian hosts were provided by quasi-species studies. The findings described in this thesis emphasize the relevance of the role of the environment in the dissemination and transmission of the HPAI H5N1 virus.
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Capacité de différents outils de typage moléculaire pour tracer Campylobacter jejuni et identifier l’origine de contamination en cas de campylobactériose / Ability of several genotyping methods to track Campylobacter jejuni and identify the source of human campylobacteriosis

Thépault, Amandine 10 January 2018 (has links)
Campylobacter est responsable de la zoonose bactérienne d’origine alimentaire la plus fréquemment reportée en Europe. Cette bactérie étant ubiquitaire, les sources et voies d’infection de l’Homme sont nombreuses. Cependant, afin de diminuer l’incidence de la maladie, il est nécessaire d’identifier les principaux réservoirs impliqués dans les infections humaines. Pour cela, nous avons dans un premier temps investigué la présence de Campylobacter dans trois réservoirs animaux (volaille, bovin, animaux de compagnie), ainsi que la diversité génétique des isolats de C. jejuni, en comparaison à celle d’isolats cliniques, à l’aide des techniques MLST (Multilocus sequence typing) et CGF (Comparative Genomic Fingerprinting). Afin d’identifier l’origine des campylobactérioses avec précision et de compenser notamment les limites techniques de la MLST, 15 marqueurs génétiques ont été sélectionnés comme marqueurs potentiellement indicateurs de l’hôte, après analyse de plus de 800 génomes de C. jejuni. Par la suite, la capacité de la MLST, la CGF40 et des 15 marqueurs à identifier l’origine des campylobactérioses a été étudiée. Ainsi, les 15 marqueurs se sont révélés être particulièrement performants pour l’attribution de sources des campylobactérioses, suivis ensuite par la MLST, tandis que la CGF40 est apparue comme étant peu adaptée. A partir des données MLST et des 15 marqueurs génétiques, une implication majoritaire des volailles et des bovins a été mis en évidence en France, tandis que les animaux de compagnie et l’environnement (comprenant eau et oiseaux sauvages) étaient faiblement impliqués. Ceci permet ainsi de renforcer les efforts de recherche relatifs aux moyens de lutte contre Campylobacter menés dans ces réservoirs. Ce travail a également permis de mettre en évidence de potentielles spécificités nationales dans la dynamique de transmission de C. jejuni à l’Homme. / Campylobacter is the causal agent of the main bacterial foodborne gastroenteritis in Europe. Since Campylobacter is frequently found in animal reservoirs, sources of human infection and transmission routes are various. However, to decrease the human burden of campylobacteriosis, it is essential to quantify the relative importance of the several reservoirs in human infections. For this purpose, we assessed the contamination of chicken, cattle and pets by Campylobacter spp., and further characterized C. jejuni isolates using MLST (Multilocus Sequence Typing) and CGF (Comparative Genomic Fingerprinting) in comparison with French clinical isolates. Then, in order to identify the most likely origin of campylobacteriosis cases in France and overcome MLST limitations in source attribution, about 800 C. jejuni genomes were analyzed which resulted in the identification of 15 genes as promising host segregating markers for source attribution. Subsequently, we assessed the ability of MLST, CGF40 and the 15 host-segregating markers to identify the most likely origin of campylobacteriosis. The 15 host-segregating markers were the most powerful in source attribution, followed by MLST, while CGF40 appeared to be not suitable for source attribution in our study. Based on MLST and the 15 markers, assignments of clinical cases emphasize the significant implication of chicken and ruminant in human infection by Campylobacter, while pets and the environment (including water and wild birds) were slightly involved, reinforcing the interest to focus control strategies on livestock. Finally this work highlights potential national variations in the transmission dynamics of C. jejuni to human.
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Frequência de anticorpos anti-Toxocara em frangos criados em sistema semi-intensivo, no Norte do Paraná, Sul do Brasil / Frequency of anti-Toxocara antibodies in broiler chickens reared under semi-intensive system, in the State of Paraná, southern Brazil

OLIVEIRA, Adilson Cardoso de 28 June 2017 (has links)
Submitted by Adriana Martinez (amartinez@unoeste.br) on 2018-02-07T17:46:54Z No. of bitstreams: 2 ADILSON OLIVEIRA.pdf: 313073 bytes, checksum: 760378e31125b9946d2bbf47c1aeafdb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-07T17:46:54Z (GMT). No. of bitstreams: 2 ADILSON OLIVEIRA.pdf: 313073 bytes, checksum: 760378e31125b9946d2bbf47c1aeafdb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-28 / Toxocariasis is an important zoonosis of worldwide distribution. The main way of transmission of the disease to human is the ingestion of soil containing embryonated eggs of Toxocara spp., the etiological agent. Studies have indicated the ingestion of raw or undercooked meat of chickens as another way of transmission. Besides, free-range chickens have been considered a good sentinel for the contamination of soil by Toxocara spp. eggs. The aim of this study was to evaluate the presence of anti-Toxocara antibodies in naturally infected broiler chickens (n=189) slaughtered in an abattoir located in Paraná, southern Brazil. The chickens were reared in a semi-intensive system by small familial farmers (n=7). An ELISA test was performed to detect the presence of anti-Toxocara IgY after serum adsorption with Ascaridia galli extract. An overall seroprevalence of 67.7% (128/189; 95% confidence interval [CI] = 61.1-74.4) was observed. The frequency of positive animals by farm ranged from 29.6% to 100%. The optical density and reactivity index indicated the possible chronicity of infection of the evaluated chickens. Associations between the presence of antibodies and the area where chickens were reared (p = 0.382) or the population density of dogs on the farm (p = 0.785) were not observed. This study shows a high frequency of Toxocara spp. infection in broiler chickens reared in semi-intensive systems and provides significant evidence that chickens are good indicator of environmental contamination by larva migrans agents. Further studies are necessary to assess the risk factors associated with poultry infection and the likelihood of toxocariasis transmission to humans via the ingestion of free-range chicken meat. / Toxocaríase é uma importante zoonose, com ampla distribuição mundial. A principal via de transmissão da doença para humanos se deve à ingestão acidental de ovos de Toxocara spp. presentes NO solo. Estudos têm descrito a infecção de seres humanos pelo consumo de carne crua ou mal cozida de frango. Os frangos criados em sistema semi-intensivo têm sido também considerados como sentinelas para a contaminação de solo por ovos de Toxocara spp. Com a finalidade de avaliar a presença de anticorpos anti-Toxocara em frangos de corte, foram colhidas 189 amostras de sangue de frangos em um abatedouro no Norte do Paraná. Os frangos foram criados em sistema colonial/caipira (sistema semi-intensivo), em pequenas propriedades rurais (n=7) pertencentes a produtores vinculados a uma associação de pequenos produtores. Os testes sorológicos foram realizados pela técnica de ELISA indireto, utilizando-se antígenos excretórios-secretórios (TES) de Toxocara canis para detecção de anticorpos IgY (IgG), com preadsorção do soro com antígenos de Ascaridia galli, para redução de reações cruzadas. Como resultado, foi obtida uma prevalência de 67,7% (128/189; IC 95%= 61,1-74,4), com uma variação de 29.6% a 100% entre as propriedades. Não foi observada correlação entre a positividade dos animais quando comparada a área (p= 0,382) e a densidade populacional de cães por propriedade (p= 0,785). Os resultados demonstraram alta frequência de anticorpos anti-Toxocara em frangos de corte criados em sistema semi-intensivo, indicando que essas aves podem ser indicadores de contaminação ambiental por agentes de larva migrans. Outros estudos são necessários para avaliar os riscos associados à transmissão de toxocaríase aos humanos pelo consumo da carne de frangos criados no sistema colonial/caipira.

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