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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.
161

Efetividade da doxiciclina na profilaxia contra letptospirose

Monteiro, Gl?ria Regina de Goes 27 June 2003 (has links)
Made available in DSpace on 2014-12-17T14:03:43Z (GMT). No. of bitstreams: 1 GloriaRGM.pdf: 347705 bytes, checksum: f20a585acbdd2c228097c779694d18db (MD5) Previous issue date: 2003-06-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Leptospirosis is a worldwide zoonosis of considerable medical and economical importance that affects humans in both urban and rural contexts, as well as domestic animals and wild fauna. Leptospira interrogans is the causative agent and is transmitted to humans by indirect contact with contaminated soil or water. The clinical syndromes include sub clinical infection, self-limited anicteric febrile illness, and severe and potentially fatal illness, known as Weil?s syndrome. In developed countries, leptospirosis is related to occupational or recreational activities while in developing countries, outbreaks occur during floods. In those regions, traditional strategies to prevent the transmission are difficulties to be implemented because of costs and lack of community acceptance. In addition, no efficient vaccine is available for human use. Several studies have suggested that chemoprophylaxis with doxycycline pre and post-exposure may be effective to prevent leptospirosis. Leptospirosis has been reported in rural areas of the State of Rio Grande do Norte, Brazil since 1985 in rice farmers who present the anicteric illness. The disease cause great social and economics impact. The study was conducted in S?o Miguel where an epidemic of leptospirosis in rice farmers was reported. The main objective was to determine the efficacy of doxycycline in preventing Leptospira exposure. A taxa de soropreval?ncia de leptospirose na popula??o estudada antes e ap?s a colheita foi de 14,2% (n=22) e de 16.6% (n=27) respectivamente. Anti-Leptospira serology was determined for 61 subjects in two instances, pre and post-exposure to potential contaminated water. There was an increased risk of 29.0 per cent in acquiring infection for individuals that did not use doxycycline. In addition, an increased risk of 30.0 % observed in farmers who did not use protection when exposed to Leptospira. The adhesion to preventive chemoprophylaxis was 55.7%. Therefore doxycycline, under specific circunstances appears to be an effective alternative to protect against leptosprirosis infection. A large sample composed of individuals to adhere to preventive therapy is needed to define time, dosage and length of use of doxycycline in this area / A leptospirose ? uma zoonose de distribui??o mundial que afeta, acidentalmente, o homem tendo como reservat?rios animais dom?sticos e silvestres. O agente causal, a Leptospira interrogans, ? transmitido ao homem, principalmente, por contato indireto com ?gua ou solo contaminados com a urina de ratos. O espectro cl?nico inclui infec??o subcl?nica, doen?a febril anict?rica e doen?a severa potencialmente fatal conhecida como s?ndrome de Weil. Em pa?ses desenvolvidos ? descrita, quase sempre, associada ? atividade profissional ou recreativa, enquanto nas regi?es em desenvolvimento epidemias tamb?m s?o associadas a enchentes. Nestas ?reas, medidas tradicionais de preven??o da doen?a, como, melhoria das condi??es sanit?rias, prote??o individual e controle de roedores s?o dif?ceis de serem implementadas por problemas econ?micos e pela baixa aceita??o da comunidade. Por outro lado, at? o momento n?o h? uma vacina eficaz para uso em humanos, mas, a quimioprofilaxia com doxiciclina tem sido apontada na literatura como uma alternativa adequada pra preven??o pr? e p?s-exposi??o de indiv?duos sob risco por determinado per?odo de tempo. Epidemias de leptospirose t?m sido relatadas na ?rea rural do Rio Grande do Norte, Brasil desde 1985, atingindo lavradores de arroz que apresentam a forma anict?rica da doen?a. Tais epidemias causam forte impacto econ?mico-social na regi?o por incapacitarem agricultores durante a ?poca da colheita do arroz e aumentarem os gastos da sa?de. O objetivo deste estudo foi avaliar a efic?cia da doxiciclina na prote??o contra infec??o por Leptospira em agricultores de arroz do munic?pio de S?o Miguel/RN, cuja taxa de soropreval?ncia antes da interven??o foi de 14,2%(n=22). Avalia??o sorol?gica pr? e p?s-colheita realizada em 61 indiv?duos demonstraram uma taxa de soroconvers?o de 8,8% (n=34) nos que utilizaram a droga e de 11,1%(n=27) naqueles que n?o utilizaram. A an?lise estat?stica revelou um risco adicional de aquisi??o da infec??o de 29% entre os agricultores que n?o utilizaram a doxiciclina, al?m de um risco adicional de 30% de adquirir a infec??o naqueles indiv?duos que trabalharam descal?os. A taxa de ades?o a quimioprofilaxia foi de apenas 55,7%. A doxiciciclina pode ser uma medida efetiva na profilaxia pr?-exposi??o de lavradores de arroz, entretanto, uma amostra maior composta por indiv?duos que apresentem maior ader?ncia ? terapia ? necess?ria para uso efetivo deste antibi?tico como profilaxia da infec??o por Leptospira nessa regi?o
162

Agentes infecciosos e dieta de carnívoros domésticos e silvestres em área de silvicultura do Alto Paranapanema: implicações para a conservação / Infectious agents and diet of domestic and wild carnivores in a silvicultural area in Alto Paranapanema: implications for conservation

Thais Rovere Diniz Reis 02 March 2012 (has links)
Apesar do estado de São Paulo ter uma área de vegetação nativa pequena e, em sua maioria, altamente fragmentada, isolada e imersa em matrizes agrícolas em propriedades privadas, seu território ainda alberga um número considerável de espécies silvestres, inclusive nessas áreas comerciais. Para a elaboração de planos de manejo ecologicamente corretos, é necessário selecionar (1) espécies-chave, como os mamíferos carnívoros; (2) fatores ecológicos primários das espécies, como a dieta e o uso do espaço; e (3) locais com histórico de uso do solo representativos da exploração espaço-temporal, como, por exemplo, Angatuba (SP) em São Paulo. Essa dissertação foi desenvolvida na Fazenda Três Lagoas e seus arredores, entre maio de 2008 e junho de 2010 e abrange três temas distintos, mas interligados. No primeiro capítulo fez-se uma introdução geral sobre os temas. No segundo avaliou-se, em quatro fazendas adjacentes, a exposição de carnívoros domésticos aos agentes infecciosos da parvovirose, raiva, cinomose e leptospirose através de exames sorológicos. Verificou-se que as prevalências de contato dos 13 cães amostrados com esses agentes patológicos, foram, respectivamente, 100%, 80%, 23% e 15,4%. As reações positivas a alguns desses agentes e sorovares, mostram que os cães domésticos tiveram contato com os agentes através de outros hospedeiros, pois esses agentes não estão presentes em vacinas. Isso demostra a importância de sua detecção na vida silvestre e no ambiente visando elaborar um manejo sanitário efetivo para a economia e saúde humana e para a vida silvestre. No terceiro capítulo estudou-se a dieta de 12 espécies de mamíferos carnívoros através da análise de 524 amostras de fezes coletadas nas Fazendas Três Lagoas e Arca. Pode-se verificar que os carnívoros presentes na área possuem hábitos onívoros, com algumas alterações da dieta em comparação com áreas mais preservadas, consumindo em grande quantidade pequenos roedores, frutos e insetos. A competição, apesar de pequena, foi constadada entre as espécies domésticas e silvestres. Verificou-se, de forma complementar, que as espécies usam mais as áreas próximas da vegetação nativa que dentro da matriz, sendo que algumas espécies estiveram restritas ao ambiente nativo. Esse estudo sugere que essas paisagens albergam somente espécies com hábitos mais plásticos e que a matriz silvicultural é permeável a alguns predadores. No quarto capítulo, estudou-se a prevalência de ectoparasitas naquelas amostras de fezes, que mostrou-se de 42,17% para ácaros, dentre eles carrapatos, e 4% de pulgas. As prevalências desses artrópodes variaram entre as espécies de carnívoros. Os ácaros foram encontrados nas fezes de todas as espécies amostradas, e as pulgas estiveram presentes em fezes de todos os canídeos, de todos os felídeos, com exceção do gato-mourisco, e do quati. Foram detectados carrapatos em fezes de espécies de hospedeiros ainda não relatadas na literatura, mostrando serem hospedeiros não-usuais, o que poderia demonstrar um aumento de sua prevalência no ambiente como consequência provável da mudança da paisagem. Essa maior carga de parasitas, juntamente com o contato frequente da fauna silvestre com os humanos e seus animais domésticos, atesta a necessidade de estudos epidemiológicos de maior amplitude nessas paisagens agrícolas. / Although the state of Sao Paulo has a small area of native vegetation, mainly fragmented, isolated and highly immersed in agricultural matrices on private properties, it still lodges a considerable number of wild species, also on these commercial areas. For elaboration of ecologically correct manegement plans, it´s necessary to select (1) key-species, as carnivore mammals; (2) species primary ecological factors, as diet and space use; and (3) representative areas of space-temporal exploration of the land, as Angatuba does on Sao Paulo. This study was carried out at Fazenda Três Lagoas and its surrounding between May 2008 and June 2010, and encloses three distinct but linked subjects. The first chapter is a general introduction of those subjects. The second one evaluates, in those four adjacent farms, domestic carnivores exposition to infectious agents of parvovirosis, rabies, canine distemper and leptospirosis through serologic examinations. The prevalence of contact of those pathological agents, in the 13 dogs, were 100%, 80%, 23% and 15.4%, respectively. The positive reactions to some of these agents and serovares show that those domestic dogs had contact to other hosts, as some of them do not compose vaccines. It shows the importance of its detention in wildlife and in the environment aiming to elaborate an effective sanitary management for economy and human health and for wildlife conservation. In the third chapter the diet of 12 species of carnivorous mammals were investigated through analysis of 524 scats collected on Fazenda Três Lagoas and Fazenda Arca. Carnivore mammals on these area have omnivores\' food habits, with some modifications on diet in comparison with those in preserved areas, consuming in a great amount small rodents, fruits and insects. The competition, although weak, occurs among the domestic and wild species. In a complementary way, it was verified that the animals use more areas closer to native vegetation than inside matrix and that some species use areas restricted to native environment. This study suggests that these landscapes only lodge species with more plastic habits and that silvicultural matrix is permeable to some predators. In the forthy chapter, it was investigated the ectoparasites prevalence in those excrement samples and revealed a prevalence of 42,17% for mites, amongst them ticks, and 4% of fleas. The prevalence of those arthropods varied between carnivore species. Mites were found in excrements of all sampled species, and fleas were found in all wild dogs and wild cats faeces, but jaguarundi, and coati. Some carnivore scats contenied different ticks showing that those mammals are non-usual hosts of them and that, possibly, there is an increase of its prevalence in the environment as probable effect of the landscape modifications. A higher parasitic load with direct contact of wildlife to humans and livestock request to carry out a more in-depth epidemiologic investigation into these agricultural landscapes.
163

Prevalência e fatores de risco para Coxiella burnetii em queijos Minas artesanais da microrregião do Serro

Faria, Letícia Scafutto de 22 August 2017 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-08T17:55:42Z No. of bitstreams: 1 letíciascafuttodefaria.pdf: 1095599 bytes, checksum: 1c63329ef1875b3086d3531350f36ccc (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-01-23T11:12:07Z (GMT) No. of bitstreams: 1 letíciascafuttodefaria.pdf: 1095599 bytes, checksum: 1c63329ef1875b3086d3531350f36ccc (MD5) / Made available in DSpace on 2018-01-23T11:12:07Z (GMT). No. of bitstreams: 1 letíciascafuttodefaria.pdf: 1095599 bytes, checksum: 1c63329ef1875b3086d3531350f36ccc (MD5) Previous issue date: 2017-08-22 / O objetivo desse trabalho foi estimar a prevalência de Coxiella burnetii em Queijo Minas Artesanal da microrregião do Serro e identificar os fatores associados à presença desse microrganismo nas propriedades estudadas. Foram sorteados aleatoriamente 55 produtores cadastrados no Instituto Mineiro de Agropecuária (IMA) para participar da pesquisa. Os produtores responderam a um questionário e foi coletada uma amostra de queijo de cada propriedade para representá-la. Nas amostras de queijo coletadas, foram realizadas as análises de Reação de Cadeia da Polimerase (PCR) para C. burnetii e sequenciamento dos produtos de DNA amplificados. Os dados provenientes das entrevistas e resultados das análises laboratoriais, uma vez sistematizados, formaram a base de dados do trabalho. A presença de DNA de C. burnetii foi considerada a variável dependente e as variáveis explicativas foram divididas em três grupos hierárquicos: distal (socioeconômicas e demográficas), intermediário (produção de queijo) e proximal (características do rebanho, produção de leite e ordenha). Os fatores associados à presença de C. burnetii nos queijos foram identificados por análises de regressão logística univariada e multivariada. Do total de amostras analisadas (n = 53), cinco (9,43%) apresentaram DNA de C. burnetii confirmado por sequenciamento. Os fatores associados com a presença de DNA de C. burnetii nos queijos foram: uso do pingo (soro- fermento) para a fabricação dos queijos (OR= 12,09), tipo de ordenha (OR= (16,45) e número de vacas em lactação (OR= 1,05). As variáveis que permaneceram no modelo final como explicativas para presença de C. burnetii nos queijos foram: número de vacas em lactação, tipo de ordenha e uso do pingo. A presença de DNA de C. burnetii nos queijos artesanais enfatiza, por um lado, a necessidade de medidas de controle mais rigorosas para que essa bactéria não esteja presente nos rebanhos de propriedades produtoras de queijos artesanais. Por outro lado, o conhecimento dos fatores associados à presença de C. burnetii nos queijos artesanais poderá auxiliar no estabelecimento de medidas preventivas e na criação de novas normas e legislação para a produção de queijos artesanais, já que essa lacuna na legislação seria algo para reflexão, dada a importância da febre Q para a saúde pública. / The objective of this study was to estimate the prevalence of Coxiella burnetii in Artisan Minas cheese of region of Serro and identify the factors associated with the presence of this organism in the properties studied. Were drawn at random 55 registered producers in the Instituto Mineiro de Agropecuária (IMA) to participate in the research. The producers responded to a questionnaire and was collected a sample of cheese at a property to represent her. The cheese samples collected, the analysis of reaction of polymerase chain reaction (PCR) to C. burnetii and sequencing of amplified DNA products. Data from the interviews and results of laboratory tests, once organized, form the basis of work data. The presence of DNA of C. burnetii was considered as the dependent variable and the explanatory variables were divided into three groups: hierarchical distal (socioeconomic and demographic), intermediate (cheese production) and proximally (characteristics of the herd, milk production and milk). The factors associated with the presence of C. burnetii in cheeses were identified by analysis of univariate and multivariate logistic regression. Of the total samples analyzed (n = 53), five (9.43%) presented DNA of C. burnetii confirmed by sequencing. The factors associated with the presence of DNA of C. burnetii in cheeses were: use of the pingo (serum- baking) for the manufacture of the cheeses (OR = 12.09), type of milking (OR = (16.45) and number of lactating cows (OR = 1.05). The variables that remained in the final model as explanatory for the presence of C. burnetii in cheeses were: number of lactating cows, milking and type use the pingo. The presence of DNA of C. burnetii in artisanal cheeses emphasizes, on the one hand, the need for more stringent control measures so that this bacteria is not present in flocks of artisanal cheese-producing properties. On the other hand, the knowledge of the factors associated with the presence of C. burnetii in artisanal cheeses may assist in establishing preventive measures and the creation of new standards and legislation for the production of artisanal cheeses, since this gap in the legislation would be something for reflection, given the importance of Q fever to public health.
164

Investigação soroepidemiológica e molecular de brucelose e leptospirose em núcleos de conservação de gado curraleiro pé duro e pantaneiro / Seroepidemiological and molecular monitoring of brucellosis and leptospirosis in nucleus of in situ conservation of curraleiro pé-duro and pantaneiro breeds

ROMANI, Alana Flávia 21 September 2012 (has links)
Made available in DSpace on 2014-07-29T15:13:48Z (GMT). No. of bitstreams: 1 TESE ALANA ROMANI.pdf: 1045802 bytes, checksum: f2ca493c65e73360592831be5ef56fb6 (MD5) Previous issue date: 2012-09-21 / The locally adapted breeds to different Brazilian ecosystems characterized as an alternative to food production, for presenting, among other characteristics, greater resistance to diseases.The main objective of this study was to evaluate the epidemiological situation of brucellosis and leptospirosis in nucleus of in situ conservation of Curraleiro and Pantaneiro bovine breeds in Cerrado and Pantanal biomes by serological and molecular diagnosis of these diseases in the livestock. We analyzed serum of 1,280 Curraleiro and 248 Pantaneiro animals on convenience sampling. We employed microscopic agglutination test, for the diagnosis of leptospirosis and the buffered acidified antigen test (Rose Bengal plate test) for brucellosis and 2-mercaptoethanol test for confirmation. The frequency of brucellosis in Curraleiro was 0.7% for animals and 25% for herds. In Pantaneiros, all animals tested were negative for Brucella abortus. The frequency of anti- Leptospira antibodies was 44.8% in Curraleiro and 51.2% in Pantaneiros, and 100% of the herds of both breeds showed positive animals. The factors associated with leptospirosis were access to wetland, abortions, vaccination against leptospirosis and practice of slaughtering in the propertyfor Curraleiro breed; and sex and age, with the highest risk for females aged between 12 and 24 months for Pantaneiro breed. Serological methods were employed above and polymerase chain reaction (PCR) for detecting infection by Brucella spp. and Leptospira spp. in cattle, to evaluate the concordance of the results of such tests. Brucellosis shows low frequency in Curraleiro cattle and is controlled in Pantaneiro. Leptospirosis was widely disseminated in nucleus of in situ conservation. In both breeds the serovars Hardjo and Wolffi were the most prevalent, which reinforce the function of bovine as a source of infection in the herd. However, the presence of reactions to serovars characteristic of wild animals suggests the involvement of local wildlife in the epidemiology of bovine leptospirosis in these nuclei of in situ conservation. The correlation of results obtained by serology and PCR to identify infection by Brucella spp. and Leptospira spp. was weak, which reinforces the idea that the diagnosis is more reliable when more than one method is employed. / As raças bovinas localmente adaptadas aos diferentes ecossistemas brasileiros caracterizam-se como uma alternativa para produção de alimentos, por apresentarem entre outras características, maior resistência a enfermidades. O objetivo geral foi avaliar a situação epidemiológica da brucelose e da leptospirose em núcleos de conservação de bovinos Curraleiros Pé Duro e Pantaneiros no Cerrado e Pantanal, utilizando métodos sorológicos e moleculares no diagnóstico de rebanho destas enfermidades. Foram testados soros de 1.280 bovinos Curraleiros e 248 bovinos Pantaneiros em amostragem de conveniência. Para diagnóstico de leptospirose empregou-se a soroaglutinação microscópica (SAM) e para brucelose adotou-se o teste de antígeno acidificado tamponado (AAT) e confirmação pelo teste de soroaglutinação lenta e 2 mercaptoetanol (2 - ME). Além dos métodos sorológicos descritos, foi empregada a reação em cadeia da polimerase (PCR) para detecção de infecção por Brucella spp. e Leptospira spp. em bovinos Curraleiros Pé Duro, para avaliar a concordância dos resultados de tais testes. A frequência de brucelose em bovinos Curraleiros foi de 0,7% para animais e 25% para rebanhos, enquanto os Pantaneiros foram soronegativos para Brucella abortus. A frequência anticorpos anti-Leptospira em bovinos Curraleiros foi de 44,8% e em Pantaneiros 51,2%. 100% dos rebanhos apresentaram animais soropositivos. Os fatores associados à leptospirose em bovinos Curraleiros foram acesso à área alagadiça, ocorrência de abortos, vacinação contra leptospirose e prática de abate na propriedade. Para bovinos Pantaneiros os fatores associados foram sexo e idade, com maior risco para fêmeas na faixa etária entre 12 e 24 meses. Conclui-se que a brucelose apresenta baixa frequência em bovinos Curraleiros Pé Duro e está controlada em Pantaneiros. A leptospirose revelou-se amplamente disseminada nos núcleos de criação de bovinos de raças localmente adaptadas. Nas duas raças os sorovares mais prevalentes foram Hardjo e Wolffi reforçando o papel dos bovinos como fonte de infecção no rebanho. A ocorrência de positividade para sorovares adaptados à fauna silvestre local sugere a participação da mesma na epidemiologia da leptospirose bovina nos núcleos de conservação das raças. A concordância dos resultados obtidos pela PCR em amostras sanguíneas e pela sorologia para identificação da infecção por Brucella spp. e Leptospira spp. foi fraca, o que reforça da necessidade de validação da PCR tendo em vista que o diagnóstico é mais confiável quando obtido por meio de vários métodos.
165

Aves silvestres como portadoras de agentes infecciosos para humanos no município de Goiânia - Goiás / Wild birds as carriers of infectious agents to humans in Goiania, Goias, Brazil

RAMOS, Talita Silva 27 April 2011 (has links)
Made available in DSpace on 2014-07-29T15:29:11Z (GMT). No. of bitstreams: 1 Dissertacao Talita Silva Ramos.pdf: 3387095 bytes, checksum: 04f2c9013d8026bdbc34d13d75a0c272 (MD5) Previous issue date: 2011-04-27 / The narrowing between humans, domestic and wild animals has increased the dissemination of infectious agents for new hosts. The result of this interaction has lead to zoonosis. Among these animals are birds, which are natural reservoirs, carriers and disseminators of several infectious agents, potentially transmissible to humans. This dissemination can occur through direct and indirect contact with migratory birds originated from smuggling of wild animals. The objective was to detect viral, bacterial and fungal agents with zoonotic potential in wild birds in the county of Goiânia, Goiás. It was carried out a systematic review to assess the State of Goiás in relation to the performance of wild birds as carries of infectious agents to humans. Blood samples and cloacal swabs were collected from 88 different species of birds, as most of them were originated from smuggling and sent to CETAS-IBAMA in Goiânia in the first semester of 2010. The collects were analyzed in the Laboratory of Animal Virology at Federal University of Goiás (UFG) and the bacteriological and fungal analyses were done in the Laboratory of Microbiology at National Service of Industrial Education (SENAI) in Anápolis, Goiás. The blood was stored in tubes without anticoagulant in order to obtain serum and it was carried out a research with Enzyme-Linked Immunosorbent to search for the antibody of influenza virus and the cause of Newcastle disease. In order to isolate and identify filamentous fungus, Candida spp, bacteria, Salmonella sp and Escherichia coli, samples were collected from cloacal excretion through swabs. In the systematic review, three articles were selected using two tests of Relevance. From the interpretation of these studies, it was proved the role of migratory birds as carriers and disseminators in short and long distances of several pathogenic virus to humans. Furthermore, there are no records or even systematic studies about this process in the state of Goiás. From 88 analyzed samples, none of them presented antibodies for the two researched virus. The analysis of samples from cloacal swabs indicated a positivity of 9,1% for Candida tropicalis , 9,1% for Salmonella sp, 1,1% for Aspergillus fumigatus, 11,4% for Candida albicans, 12,5% for Candida krusei, 27,3% for Candida spp, and 43,2% for Escherichia coli. The literature review suggests that further researches should be carried out as the distribution of this zoonosis can possibly be wider, even in the State of Goiás. Regarding the negative results for the viral agents, they indicate that part of the wild birds in Goiânia-Goiás did not have contact with influenza and Newcastle viral antigens yet. Therefore they are not carriers of these photogenes. In relation to presumptive identifications of pathogenic bacteria and fungal agents in wild birds, they confirm the possibility of transmission of these agents among animals and to humans. Besides, this study also reinforces that researches about zoonosis transmitted by wild birds in the state of Goiás are still recent and incipient, highlighting the need of continuation of these studies in the region. / O estreitamento entre a população humana e os animais domésticos com animais silvestres aumentou a disseminação de agentes infecciosos para novos hospedeiros, sendo uma importante consequência, as zoonoses. Entre estes animais, estão as aves, que são reservatórios naturais, portadores e disseminadores de diversos agentes infecciosos, potencialmente patogênicos transmissíveis aos humanos. A disseminação pode ocorrer por meio de contato direto ou indireto com aves migratórias e provenientes do tráfico de animais silvestres. O objetivo foi detectar agentes virais, bacterianos e fúngicos, com potencial zoonótico em aves silvestres no município de Goiânia-Goiás. Foi conduzida uma revisão sistemática para avaliar com ênfase, o Estado de Goiás em relação a atuação das aves silvestres como portadoras de agentes infecciosos para humanos. Amostras de sangue e de swabs cloacais foram coletadas em 88 aves de distintas espécies, sendo a maioria, proveniente do tráfico e encaminhadas ao CETAS-IBAMA de Goiânia. As coletas foram realizadas em cinco incursões ao CETAS no primeiro semestre de 2010. As análises virais foram realizadas no Laboratório de Virologia Animal da UFG e as análises bacteriológicas e fúngicas no Laboratório de Microbiologia do SENAI em Anápolis. O sangue foi coletado em tubos sem anticoagulante para obtenção de soro e com o ensaio imunoenzimático indireto pesquisou-se anticorpos para os vírus influenza e causador da doença de Newcastle. As amostras de excreção cloacal foram coletadas por meio de swabs e realizouse o isolamento e identificação de fungos filamentosos, Candida spp, Salmonella sp e Escherichia coli. Na revisão sistemática, três artigos foram selecionados por meio de dois Testes de Relevância e a partir da interpretação destes estudos foi comprovado o papel das aves silvestres como portadoras e disseminadoras, a curta ou longa distância, de vários agentes infecciosos aos humanos e que não existem registros ou estudos sistemáticos sobre este processo no Estado de Goiás. Das 88 amostras analisadas, nenhuma apresentou anticorpos para os dois vírus pesquisados. As análises das amostras procedentes de swabs cloacais houve uma positividade de 9,1% para Candida tropicalis, 9,1% para Salmonella sp, 1,1% para Aspergillus fumigatus, 11,4% para Candida albicans, 12,5% para Candida krusei, 27,3% para Candida spp e 43,2% para Escherichia coli. Na revisão observou-se que novos estudos devem ser realizados, pois a distribuição destas zoonoses, possivelmente deve ser mais ainda mais ampla, inclusive em relação ao Estado de Goiás. Quanto aos resultados negativos para os agentes virais, estes sugerem que uma parcela das aves silvestres circulantes em Goiânia, ainda não entrou em contato com os agentes virais influenza e Newcastle, não sendo, portanto, portadoras destes patógenos. Em relação às identificações presuntivas de agentes bacterianos e fúngicos, em aves silvestres, estas confirmam a possibilidade da transmissão destes agentes entre os animais, incluindo os humanos. Além disso, este estudo reforça que ainda são incipientes as investigações desenvolvidas na área de zoonoses transmitidas por aves silvestres no Estado de Goiás, ressaltando a necessidade da continuidade destes estudos na região.
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Prevalência e distribuição espacial da cisticercose e fasciolose bovina no estado de Goiás / Prevalence and spatial distribution of cysticercosis and fasciolosis bovine in the state of Goiás

Aquino, Fernanda Martins de 08 March 2017 (has links)
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No. of bitstreams: 2 Dissertação - Fernanda Martins de Aquino - 2017.pdf: 2825789 bytes, checksum: 21dd668e99af981f702f5b0d0823a01c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-08 / Amongst the several parasite-diseases that may be found on the bovine species slaughter line, cysticercosis surely is the most frequent one. Besides being a zoonosis and a public health issue, it also causes great economic losses on the Brazilian meat productive chain. On the other hand, fasciolosis, also considered a zoonosis, has a lower occurrence when compared to cysticercosis, fact that may be due to its epidemiologic dynamics. Aiming to learn the level of infection of these zoonosis in the bovine herd of the state of Goiás, this project was undertaken with the scope of determining the prevalence and spatial distribution, as well to evaluate the association with some epidemiologic variables with the occurrence of these diseases and also to estimate economic losses inflicted on the producers and industries. A retrospective study was carried out on a total of 23.255.979 animals slaughtered per year, mesoregions and microregions. The data were used to create one epidemiologic map for bovine cysticercosis and one for bovine fasciolosis, gathering all cities of the state of Goiás. A prevalence of bovine cysticercosis on the state of Goiás of 0,53% (CI 95% 0,5295 – 0,5354), where the percentage of viable cysticercosis was 42,31%, non-viable cysticercosis 57,69% and the presence of bovine fasciolosis was de 0,0026% (CI 95% 0,0024 – 0,0028). The mesoregion Centro presented a greater chance (OR = 4,44) of finding positive cattle for cysticercosis when compared to the mesoregions Norte (OR = 1) and Nordeste (OR = 1,02), whilst the mesoregions diagnosed with greater chances of finding animals positive for fasciolosis, due to having a greater effective herd (p ≤ 0,05), were Noroeste, Sul, part of the region Centro and two cities of the region Leste of the state. The losses estimated for the evaluated period, from 2007 to 2014, ranged from R$ 64.809.817,50 (US$ 20.574.545,24) due to the presence of cysticercosis, and around R$ 15.072,75 (US$ 4.785) due to the presence of Fasciola hepatica in bovine liver. Such results outline the importance of developing strategic measures and action policies to try and control the spreading of these relevant zoonosis. / Dentre os vários parasitos que podem ser encontrados na linha de abate da espécie bovina, é notório que a cisticercose é a de maior frequência. Além de ser uma zoonose e um problema de saúde pública, ainda causa grandes prejuízos econômicos na cadeia produtiva de carnes do Brasil. Por outro lado a fasciolose, também considerada uma zoonose, possui uma menor ocorrência quando comparada à cisticercose, fato que pode estar atribuído a sua dinâmica epidemiológica. Visando conhecer o nível de infecção destas zoonoses no rebanho bovino goiano, realizou-se este trabalho com o objetivo de determinar a prevalência e a distribuição espacial, além de avaliar a associação de algumas variáveis epidemiológicas com a ocorrência destas enfermidades nos animais e estimar as perdas econômicas causadas aos produtores e indústrias. Foi realizado um estudo do tipo retrospectivo referente a um total de 23.255.979 animais abatidos agrupados por ano, mesorregiões e microrregiões de Goiás. Os dados foram utilizados para criar um mapa epidemiológico da cisticercose bovina e um mapa epidemiológico da fasciolose bovina abrangendo todos os municípios goianos. A prevalência de cisticercose bovina no estado de Goiás foi de 0,53% (IC 95% 0,5295 – 0,5354), sendo a porcentagem de cisticercose viável 42,31% e cisticercose inviável 57,69% e a prevalência de fasciolose bovina de 0,0026% (IC 95% 0,0024 – 0,0028). A mesorregião Centro apresentou maior chance (OR = 4,44) de encontrar bovinos positivos para a cisticercose quando comparada as mesorregiões Norte (OR = 1) e Nordeste (OR = 1,02), enquanto as mesorregiões diagnosticadas com chances mais elevadas de se encontrar animais com fasciolose, porque continham maior rebanho efetivo (p ≤ 0,05) foram a Noroeste, Sul, parte da região Centro e dois municípios da região Leste do estado. As perdas estimadas para o período analisado, de 2007 a 2014, foram de R$ 64.809.817,50 reais (US$ 20.574.545,24 dólares) devido à presença da cisticercose no rebanho e cerca de R$ 15.072,75 reais (US$ 4.785 dólares) devido à presença de Fasciola hepatica no fígado de bovinos. Os resultados encontrados neste trabalho destacam a importância de se realizar medidas e ações políticas estratégicas na tentativa de controlar a disseminação destas importantes zoonoses.
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Leptospirose animal: estudos para o desenvolvimento de vacinas recombinantes / Leptospirose animal: estudos para o desenvolvimento de vacinas recombinantes

Felix, Samuel Rodrigues 01 February 2013 (has links)
Made available in DSpace on 2014-08-20T14:37:53Z (GMT). No. of bitstreams: 1 tese_samuel_felix.pdf: 483417 bytes, checksum: 782ad0a9939b35b83a255622221d018c (MD5) Previous issue date: 2013-02-01 / Leptospirosis is a disease caused by pathogenic spirochetes of the Leptospira genus. This zoonosis of worldwide distribution causes veterinarian and public health issues, especially in underdeveloped and developing countries with tropical and subtropical climates. In veterinary medicine, leptospirosis is important both as a clinical problem, causing illness in domestic animals, and an economic problem, causing productive and reproductive losses in commercial herds. Vaccination of these animals is applied, however protection conferred by these conventional vaccines is limited, and the carrier status is not always avoided. Recombinant outer membrane proteins seem to be the most promising antigens to replace the traditional bacterins (whole cell inactivated preparations), but thus far none of the tested proteins have turned satisfactory results. The goal of this study was to assess recombinant antigens and vaccine preparations, regarding their capability of producing protective immunity in hamsters, against lethal leptospirosis. Moreover, heterologous protection was sought, and assessed. The prevalence anti-Leptospira antibodies in stray dogs from the city of Pelotas was assessed using serogroups Icterohaemorrhagie and Canicola antigens. Several experiments were conducted to assess the protective potential of previously described leptospiral proteins. Twenty seven proteins were used to immunize hamsters which were then challenged with virulent Leptospira. Furthermore, leading vaccine candidates, LipL32 and LigB, were assessed regarding their protective potential when co-administered with traditional bacterins in previously established heterologous challenge experiments. A total of 28.96% of the animals tested were seropositive for the disease in the prevalence assay. Of the 27 antigens tried, two were shown to have some protective potential. Although no protection was demonstrated in the coadministration experiment, leptospiral bacterins seem to have some immunestimulating activity. / A leptospirose é uma doença causada por espiroquetas do gênero Leptospira. É uma zoonose de ampla distribuição geográfica, sendo um problema de saúde pública e veterinária, principalmente em países subdesenvolvidos e em desenvolvimento de clima tropical e subtropical. Em medicina veterinária, a leptospirose é uma doença importante tanto para a clínica quanto para a produção, devido ao risco à saúde pública, perdas reprodutivas e óbitos. A vacinação animal é realizada como medida de prevenção da enfermidade, entretanto, a proteção conferida pelas vacinas comerciais é limitada e não evita a condição de portador. Os antígenos protéicos da membrana externa parecem ser a melhor alternativa para substituir as vacinas atualmente disponíveis, porém, após diversos estudos, nenhum apresentou resultados satisfatórios. O objetivo deste trabalho foi avaliar antígenos recombinantes e preparações vacinais, capazes de conferir proteção de amplo espectro, em hamsters, contra leptospirose letal. A prevalência da leptospirose em cães da cidade de Pelotas foi aferida em um ensaio de diagnóstico sorológico usando como antígeno cepas dos sorogrupos Icterohaemorrhagie e Canicola. Em uma série de experimentos de prospecção de alvos, grupos de hamsters foram vacinados com diferentes proteínas recombinantes e posteriormente desafiados com cepa virulenta de Leptospira sp. Após o desenvolvimento de modelo para avaliação de proteção contra desafios heterólogos, as proteínas rLipL32 e rLigBNI foram avaliadas quando coadministradas com bacterinas (preparações de células inteiras inativadas por calor) em hamsters, sofrendo posterior desafio com quatro cepas de sorogrupos diferentes. Uma soroprevalência de 28,96% foi encontrada nos ensaios de prevalência. Duas de 27 proteínas recombinantes triadas foram identificadas como possíveis imunógenos. Apesar da falta de proteção demonstrada no experimento de coadministração de proteína e bacterina contra desafio homólogo ou heterólogo, a bacterina parece ter ação imunoestimulante.
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Identificação molecular e perfil sorológico de Leptospira spp. isolada de gambás-de-orelha-branca (Didelphis albiventris) no sul do Brasil / Molecular identification and serological profile of Leptospira spp. isolated of white-eared-opossum (Didelphis albiventris) in South of Brazil

Jorge, Sérgio 20 July 2009 (has links)
Made available in DSpace on 2014-08-20T14:37:58Z (GMT). No. of bitstreams: 1 dissertacao_sergio_jorge.pdf: 980348 bytes, checksum: 9e56cf9be902454868ace419c988ca33 (MD5) Previous issue date: 2009-07-20 / Leptospirosis is a zoonotic disease that occurs all over the world, particularly in developing countries, caused by bacteria of the genus Leptospira. Several marsupial species are considered susceptible to infection caused by a wide variety of Leptospira serovars, acting as reservoirs. In this work were collected serum and urine samples of 33 White-eared opossum, trapped within distinct locations of Capão do Leão and Pelotas cities, in the South of Brazil, aiming to detect antibodies and to isolate leptospires. Serum samples were screened against a panel of 58 Leptospira spp and Leptonema illini serovars using the microscopic agglutination test (MAT). To attempt isolation, urine samples from all animals were inoculated in culture medium.EMJH enriched with 10% of supplement Difco® One pathogenic serovar was isolated after two months of inoculation, and is first isolate the country for this animal species and was characterized by PCR using primers for 16S and Lipl32 genes. The technique of partial sequencing of the rpoB gene was used to identify the genomic specie. The isolated strain belongs to the specie L. borgpetersenii, which along with L .interrogans are the main cause disease in humans. The isolate, was tested on MAT using dog, cattle and human sera. Cut off titer of 50 was used for domestic animal sera and 25 for human and opossum sera. Both human and animal sera presented agglutination on MAT to isolated strain corresponding to 3.3% (2/60), 28.33% (17/60) and 1.67% (1/60) in human, dog and cattle sera, respectively. The opossum sera presented 36.36% (12/33) of reaction. These findings suggest a probable white-eared opossum role in the maintenance of pathogenic Leptospira on the environment since low titer sera and urine elimination were observed. These animals could be important reservoirs of Leptospira serovars for human and domestic animals. / A Leptospirose é uma antropozoonose de ocorrência mundial, particularmente nos países em desenvolvimento, causada por bactérias do gênero Leptospira. Várias espécies de marsupiais e didelfídeos são consideradas suscetíveis a infecção causada por uma grande variedade de sorovares patogênicos de Leptospira spp. tendo sido considerados possíveis hospedeiros deste agente. Neste trabalho foram coletadas amostras de soro e urina de 33 gambás-de-orelha-branca (Didelphis albiventris), capturados em diferentes regiões dos municípios do Capão do Leão e Pelotas, no sul do Brasil, com o objetivo de detectar anticorpos e isolar leptospiras. As amostras de soro foram testadas por aglutinação microscópica (MAT), utilizando 58 sorovares de Leptospira spp. e 1 de Leptonema. Para o isolamento, amostras de urina foram inoculadas em meio de cultura EMJH enriquecido com 10% de suplemento Difco®. Um sorovar patogênico foi obtido da urina, sendo o primeiro isolado do país para esta espécie, e foi caracterizado quanto ao gênero e patogenicidade por PCR utilizando primers para os genes 16S rDNA e Lipl32. A técnica de seqüenciamento parcial do gene rpoB foi utilizada para identificar a espécie genômica. A cepa isolada pertence à espécie L. borgpertersenii,, que juntamente com L. interrogans são as principais causadoras de doença em humanos. Anticorpos anti isolado de gambá foram avaliados em amostras sorológicas de 60 cães, 60 bovinos, 60 humanos e dos 33 gambás capturados através da MAT. Os soros humanos apresentaram reação de 3,3% (2/60), 28,33% (17/60) em soros caninos, 1,67% (1/60) em soros bovinos e 36,36% (12/33) em soros dos gambás capturados no estudo. Esses dados sugerem o envolvimento do gambá-de-orelha-branca na manutenção de leptospiras no ambiente, uma vez que estando infectados por sorovares patogênicos podem eliminar o agente pela urina e infectar direta ou indiretamente animais domésticos e conseqüentemente o homem.
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Viruses in rodents : from field work to virus discovery and characterization / Les virus chez les rongeurs : De la capture à la découverte et caractérisation de virus

Yama, Ninon Ines 27 November 2012 (has links)
Les maladies émergentes représentent actuellement 65% de toutes les pathologies infectieuses récentes. Récemment, un nombre croissant de nouveaux virus a été associé à de petits mammifères terrestres, plus particulièrement à des rongeurs, désignant ce groupe comme étant l'une des possibles sources de dangereuses pathologies émergentes et ré-émergentes. Actuellement, la réaction en chaîne par polymérase (PCR) est l'outil principal utilisé pour la détection d'agents pathogènes dans la diagnostique de routine et dans la recherche. Or, plusieurs recherches ont montré que certaines substances inhibent la PCR, causant de faux résultats. Aussi, nous avons lancé un programme de capture de rongeurs pour le dépistage de virus connus et non identifiés. Au total 1441 rongeurs ont été capturés pendant des campagnes organisées en Europe et Afrique entre 2002 et 2011. Tout d'abord, nous avons examiné l'inhibition de la PCR et étudié les différentes techniques de traitement d'échantillons qui favorisent la réduction de la quantité d'inhibiteurs dans les échantillons de rongeurs. Parmi les techniques d'extraction évaluées, l'EZ1 virus mini kit et le réactif d'extraction RNAnow se sont avéré plus efficaces que le NucleoSpin virus kit ou le réactif d'extraction TRIzol. De même, l'utilisation des poumons et de reins était préférable à l'utilisation du foie et de la rate. Aucune différence significative n'a été observée entre le stockage à -80°C et le stockage dans le réactif RNAlater. Nous avons conduit le dépistage des virus, en utilisant les tests moléculaires et la culture cellulaire. Deux nouvelles souches de virus ont été isolées, séquencées et caractérisées. / Emerging diseases currently represent 65% of recent major disease outbreaks. Of them, 75% are associated with wildlife. Recently, an increasing number of newly discovered viruses have been associated with small terrestrial mammals, particularly with rodents, pointing at this group as one of the most dangerous potential sources of emerging or re-emerging diseases. To meet these challenges for public health, a proper surveillance becomes necessary, which passes by detection of pathogens in human and risky groups of animals, including field investigations. Yet this can be achieved only by using proper techniques of samples treatment and pathogen detection. Currently, polymerase chain reaction (PCR) is the main tool used for the detection of pathogens in routine diagnostic and research. Yet, several researches showed that some substances can inhibit PCR, causing false-negative results. Therefore, we initiated a screening program targeting rodents for the presence of known and unidentified viruses. A total of 1441 rodents were trapped during field campaigns organized in Europe and Africa, between 2002 and 2011. At first we investigated on PCR inhibitors and discussed techniques of treatment of samples allowing reducing the influence of inhibitors in rodent samples. Among the extraction techniques tested, EZ1 virus mini kit and RNAnow extraction reagent were more effective than NucleoSpin virus kit or TRIzol extraction reagent. Also, the use of lungs and kidneys was preferable to the use of liver and spleen, the quantity of inhibitors being higher in the last two organs. No significant difference was observed between storage at -80°C, or in RNAlater RNA stabilization reagent.
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Investigations on the occurrence of infections with hepatitis E virus and related viruses in zoo animals

Spahr, Carina 27 March 2020 (has links)
Introduction Hepatitis E is a worldwide distributed disease, which is caused by the hepatitis E virus (HEV). In addition to humans, domestic pigs, wild boars, rabbits and dromedaries can be subclinically infected as reservoir animals with the zoonotic HEV genotypes 3, 4 and 7. In addition, HEV and HEV-like viruses have been described sporadically in other mammals, as well as in birds and fish, although their distinct role as reservoirs or carriers of the virus is still unclear. Aims The aim of the study was therefore to analyse in more detail the importance of different mammalian species, which do not belong to the known HEV reservoirs, for the epidemiology of HEV infections, thus enabling a better assessment of the risk of virus transmission by these animal species. Material and Methods Fourteen non-human primate species and 66 other mammal species, as well as Norway rats (Rattus norvegicus) and feeder rats (Rattus norvegicus forma domestica) from German zoos were selected for the investigations. In total 259 individual non-human primate sera and 244 individual mammalian sera of clinically healthy zoo animals were analysed for the presence of HEV-specific antibodies (ab) using a species-independent double-antigen sandwich ELISA. The non-human primate sera were additionally examined using a commercial human ELISA. Real-time reverse-transcription (RT)-PCR, nested broad-spectrum RT-PCR and a rat HEV-specific RT-PCR were used to detect the HEV genome in sera of mammals and rat liver samples. A commercial and an in-house method were used for the DNA sequencing. Results HEV-specific ab were detected in 3.9% (10/259) of the non-human primate sera (4 species) and 11.5% (28/244) of the mammalian sera (16 species). The highest detection rates were recorded with 33.3% (9/27) in porcines and with 27.0% (10/37) in carnivores. HEV-RNA was detected in a clinically healthy female Syrian brown bear (Ursus arctos syriacus) and in 8 of the investigated Norway rats. Sequence analysis identified the virus as rat HEV; the viruses from the bear and the free-ranging rats from the same zoo showed a high nucleotide sequence identity (94.6%–97.8%). Because of the small number of samples due to the small populations within the individual zoos, further statistical evaluations were not carried out. Conclusions The results show that non-human primates in zoos may be infected with HEV or HEV-like viruses; however, the low ab detection rates together with the negative genome detection argue against a high risk of virus transmission to humans. The study in other zoo-housed mammalian species was able to significantly increase the number of animal species with indications of HEV infections. In most animal species, only rare evidence and low detection rates were available, which can best be explained by “spillover-infections”. In addition to the expected high detection rate in porcine species, the high percentage of HEV antibody-positive carnivores is remarkable. Their role as possible HEV reservoir animals should therefore be clarified in further investigations. The detection of rat HEV in the serum of the bear and its high nucleotide sequence identity with the HEVs of the pest rodents provides first evidence of transmission of this virus species between rodents and carnivores.:List of content List of figures List of tables List of abbreviations 1 General introduction 1.1 Discovery of HEV 1.2 Taxonomy 1.3 Morphology 1.4 Genomic organisation 1.5 Viral replication 1.6 Hepatitis E in humans 1.7 Tools for HEV diagnosis 1.8 Therapy 1.9 Animal infections with HEV and HEV-like viruses 1.10 Experimental infections of animals 1.11 Geographical distribution 1.12 Transmission pathways 1.13 Epidemiology 1.14 Prevention 2 Aims of the study 3 Publications 3.1 Publication I 3.1.1 Summary of Publication I 3.1.2 Key messages of Publication I 3.1.3 Own contribution to Publication I 3.2 Publication II 3.2.1 Summary of Publication II 3.2.2 Key messages of Publication II 3.2.3 Own contribution to Publication II 3.3 Publication III 3.3.1 Summary of Publication III 3.3.2 Key messages of Publication III 3.3.3 Own contribution to Publication III 4 General discussion 4.1 HEV infections in various animal species 4.2 Prevalence of natural HEV infections in non-human primates 4.3 Prevalence of natural HEV infections in other zoo-housed mammals 4.4 Transmission pathways of HEV in a zoo-setting 4.5 Risk of virus transmission from zoo animals to humans 5 Conclusion and perspectives 6 Summary 7 Zusammenfassung 8 References List of animals investigated in the study List of publications Acknowledgements / Einleitung Hepatitis E ist eine durch das Hepatitis E-Virus (HEV) verursachte, weltweit verbreitete Erkrankung. Neben dem Menschen können Hausschwein, Wildschwein, Kaninchen und Dromedar als Reservoirtiere subklinisch mit den zoonotischen HEV-Genotypen 3, 4 und 7 infiziert werden. Darüber hinaus wurden HEV und HEV-ähnliche Viren vereinzelt bei weiteren Säugetieren, sowie Vögeln und Fischen beschrieben, wobei deren genaue Rolle als Reservoir oder Überträger des Virus bislang unklar ist. Ziele Ziel der Arbeit war es deshalb, die Bedeutung verschiedener Säugetierarten, die nicht zu den bekannten HEV-Reservoiren gehören, für die Epidemiologie der HEV-Infektionen besser zu erfassen und dadurch das Risiko einer Virusübertragung durch diese Tierarten besser abzuschätzen. Material und Methoden Vierzehn Affenarten und 66 weitere Säugetierarten, sowie Wanderratten (Rattus norvegicus) und Futterratten (Rattus norvegicus forma domestica) aus deutschen Zoos wurden für die Untersuchungen ausgewählt. Insgesamt wurden 259 individuelle Affenseren und 244 individuelle Säugerseren klinisch gesunder Zootiere mittels eines Spezies-unabhängigen Doppel-Antigen-Sandwich-ELISAs auf das Vorhandensein von HEV-spezifischen Antikörpern (AK) untersucht. Die Affenseren wurden zusätzlich mittels eines kommerziellen humanen ELISAs untersucht. Real-time reverse-transcription (RT)-PCR, nested broad-spectrum RT-PCR sowie eine Ratten-HEV-spezifische RT-PCR wurden für den HEV-Genomnachweis in Seren der Säuger und in Ratten-Lebern verwendet. Für die DNA-Sequenzierungen wurden eine kommerzielle und eine In-house-Methode verwendet. Ergebnisse In 3,9% (10/259) der Affenseren (4 Arten) und 11,5% (28/244) der Säugerseren (16 Arten) wurden HEV-spezifische AK nachgewiesen. Die höchsten Nachweisraten wurden mit 33,3% (9/27) in Schweineartigen und 27,0% (10/37) in Fleischfressern ermittelt. HEV-RNA wurde in einer klinisch gesunden Syrischen Braunbärin (Ursus arctos syriacus), sowie in 8 der untersuchten Wanderratten nachgewiesen. Die Sequenzanalyse identifizierte das Virus als Ratten-HEV; die Viren aus der Bärin und aus den wildlebenden Ratten desselben Zoos zeigten eine hohe Nukleotidsequenz-Identität (94,6%–97,8%). Weitergehende statistische Auswertungen wurden wegen der geringen Probenzahlen aufgrund der kleinen Populationen innerhalb der einzelnen Zoos nicht durchgeführt. Schlussfolgerungen Die Ergebnisse zeigen, dass Affen in Zoos mit HEV oder HEV-ähnlichen Viren infiziert sein können, jedoch sprechen die geringen AK-Nachweisraten zusammen mit den negativen Genomnachweisen gegen ein hohes Übertragungsrisiko auf den Menschen. Die Studie an anderen Säugetierarten in Zoos konnte die Zahl der Tierarten mit Hinweisen auf HEV-Infektionen deutlich erhöhen. Bei den meisten Tierarten lagen nur seltene Nachweise und niedrige Detektionsraten vor, die am besten durch „Spillover-Infektionen“ erklärt werden können. Neben der erwarteten hohen Nachweisrate bei Schweineartigen ist der hohe Prozentsatz an HEV AK-positiven Fleischfressern bemerkenswert, weshalb deren Rolle als mögliche HEV-Reservoirtiere in weiteren Untersuchungen geklärt werden sollte. Der Ratten-HEV-Nachweis im Serum der Bärin, sowie dessen hohe Nukleotidsequenz-Identität zu den HEVs der Schadnager geben erstmals Hinweise auf eine Übertragung dieser Virusart zwischen Nagern und Fleischfressern.:List of content List of figures List of tables List of abbreviations 1 General introduction 1.1 Discovery of HEV 1.2 Taxonomy 1.3 Morphology 1.4 Genomic organisation 1.5 Viral replication 1.6 Hepatitis E in humans 1.7 Tools for HEV diagnosis 1.8 Therapy 1.9 Animal infections with HEV and HEV-like viruses 1.10 Experimental infections of animals 1.11 Geographical distribution 1.12 Transmission pathways 1.13 Epidemiology 1.14 Prevention 2 Aims of the study 3 Publications 3.1 Publication I 3.1.1 Summary of Publication I 3.1.2 Key messages of Publication I 3.1.3 Own contribution to Publication I 3.2 Publication II 3.2.1 Summary of Publication II 3.2.2 Key messages of Publication II 3.2.3 Own contribution to Publication II 3.3 Publication III 3.3.1 Summary of Publication III 3.3.2 Key messages of Publication III 3.3.3 Own contribution to Publication III 4 General discussion 4.1 HEV infections in various animal species 4.2 Prevalence of natural HEV infections in non-human primates 4.3 Prevalence of natural HEV infections in other zoo-housed mammals 4.4 Transmission pathways of HEV in a zoo-setting 4.5 Risk of virus transmission from zoo animals to humans 5 Conclusion and perspectives 6 Summary 7 Zusammenfassung 8 References List of animals investigated in the study List of publications Acknowledgements

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