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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

Ocorrência e caracterização de rotavírus em frangos de corte, poedeiras e matrizes de criações comerciais brasileiras / Occurrence and characterization of rotavirus in broilers, layers and broiler breeders from Brazilian poultry farms

Laila Andreia Rodrigues Beserra 02 July 2013 (has links)
Os rotavírus estão entre os principais causadores de diarreia em humanos e animais, inclusive em mamíferos e aves. Os sintomas da doença geralmente incluem diarreia e depressão, aumento da mortalidade, e \"runting and stunting syndrome\", caracterizado principalmente por perda de peso, também tem sido atribuído a infecções por rotavírus em aves. O capsídeo externo da partícula viral é formado pelas proteínas estruturais VP4 e VP7 que possuem antígenos de neutralização baseados nos quais os rotavírus são classificados em genotipos P e G, respectivamente. O capsídeo intermediário é formado pela VP6 que define os grupos de rotavírus de A-G de acordo com a reatividade de anticorpos ou sequenciamento nucleotídico desta proteína. A proteína não estrutural NSP5 está envolvida no processo de replicação viral, sendo essencial para a formação dos viroplasmas. Este estudo teve o objetivo de pesquisar a frequência de ocorrência de rotavírus dos grupos A e D, em amostras fecais de aves de diferentes criações comerciais brasileiras, seguida da caracterização dos genotipos P e G, dos rotavírus do grupo A, através de sequenciamento nucleotídico. Para isso, 111 pools de amostras fecais foram processados através das técnicas de ELISA, PAGE e RT-PCR (NSP5), resultando em 43 (38,73%) amostras positivas pelas três técnicas. Definiram-se os genotipos G5, G8 e G11 através de RT-PCR (VP7) e o genotipo G19 após reação de RT-PCR seguida de sequenciamento nucleotídico. Definiu-se ainda o genotipo P[31] a partir do sequenciamento de amostras positivas por RT-PCR (VP4). Das 111 amostras processadas por RT-PCR visando o gene codificador da VP6, obtiveram-se 4 sequências que confirmaram tratar-se de rotavírus do grupo D. Os genotipos G5, G8 e G11 estão relacionados a surtos em bovinos e suínos, enquanto que os genotipos G19 e P[31] estão descritos em aves. Conclui-se que os rotavírus encontram-se amplamente disseminados nas criações comerciais brasileiras devido à elevada frequência da ocorrência e que existe a possibilidade de transmissão interespécie. / Rotavirus are a major cause of diarrhea in humans and animals, including several mammalian and avian species. The symptoms of the disease generally include diarrhea and depression, increased mortality and the chronic runting and stunting syndrome mainly characterized by weight loss have also been linked to rotavirus infections of birds. The outer layer of the virus particle is formed by VP4 and VP7 proteins, which possess neutralization antigens. Based on VP7 and VP4 the rotavirus are classified into genotypes G and P respectively. The intermediate layer consists of VP6 which defines the rotavirus groups. Based on the antibody reactivity and sequence identity of VP6, seven rotavirus groups (A to E) have been defined. The NSP5 are involved in viral replication and they are essential for the formation of viroplasm. Here we report the occurrence of group A and D rotavirus in feces of broilers, layers and broiler breeders from Brazilian poultry farms. A total of 111 pools of intestinal contents were processed in this study, using a ELISA, PAGE and RT-PCR (NSP5) techniques. Out of 111 pools of fecal samples tested, 43 showed positive results (38.73%) for rotavirus. Were typed the G5, G8 e G11 genotypes using the RT-PCR (VP7) and the G19 genotype using a RT-PCR followed by nucleotide sequencing reaction of the amplicons. Was defined the P[31] genotype using the RT-PCR (VP4) technique followed by nucleotide sequencing reaction. Out of 111 pools of fecal samples tested by RT-PCR (VP6), 4 showed positive results for rotavirus of group D. The G5, G8 and G11 are typical bovine and porcine rotavirus genotypes, whereas the G19 and P[31] genotypes are found in birds. As a conclusion, rotavirus is widely spread in commercial Brazilian poultry farms due to the high frequency of occurrence and there is the possibility of interspecies transmission.
162

Métodos clássicos e moleculares para avaliação da qualidade virológica de lodo de esgoto e de água de reúso: determinação da eficiência e limites de detecção. / Standard and molecular methods for surveillance of human enteric viruses in sludge and reclaimed water: efficiency and detections limits.

Luana de Cássia Umeda 20 August 2012 (has links)
Os vírus entéricos humanos são encontrados no esgoto e em subprodutos dos processos de tratamento. Recentemente vem sendo recomendados como indicadores de qualidade microbiológica em normas da legislação brasileira e também nas de outros países, mas ainda com parâmetros a definir. O objetivo do estudo é a avaliação e a comparação entre métodos clássicos e moleculares aplicados à detecção de vírus entéricos em amostras de água de reúso e de lodo, visando subsidiar a legislação brasileira. Ensaios de semeadura experimental de protótipos de rotavírus e de adenovírus foram realizados nas matrizes ambientais e os vírus detectados por métodos clássicos (cultivo celular e reação de imunoperoxidase) e moleculares (PCR/nested-PCR, RT-PCR e ICC-PCR), determinando-se os limites de detecção de cada método para cada matriz. A pesquisa de rotavírus e adenovírus presentes naturalmente em 25 amostras de água de reúso e em 25 de lodo possibilitou a comparação dos métodos propostos. O ICC-PCR mostrou ser o método mais factível a ser aplicado na área de saneamento. / Human enteric viruses are common contaminants of raw sewage and subproducts of sewage treatment processes. In recent years, those viruses were recommend as new microbiological indicators in different matrices in Brazilian legislation and others countries, although some questions should be elucidated. At present, the aim was to evaluate and compare the efficiencies of standard and molecular virological methods for detection of human enteric viruses in sludge and reclaimed water samples. Rotavirus and adenovirus were experimentally spiked in the proposed matrices and virus recovery and detection limits established for each method and matrice. Viruses naturally presented in 25 samples of sludge and 25 samples of reclaimed water were assayed by all methods and results evaluated and compared for statistical significance. From all methods evaluated, ICC-PCR showed to be the most suitable for virus surveillance in sludge and reclaimed water.
163

Diversidade sorológica e molecular de rotavírus identificados em humanos em São Paulo, Brasil. / Serological and molecular diversity of human rotavirus in São Paulo, Brazil.

Veridiana Munford 13 September 2007 (has links)
De um total de 187 amostras fecais coletadas no ambulatório do Hospital Universitário/USP, entre 1994 a 1996, 54 (28,9%) foram positivas para rotavírus. Entre as amostras caracterizadas por EGPA foram identificados nove perfis eletroforéticos longos, dois curtos e um tipo não usual. O subgrupo II e o sorotipo G2 foram os mais freqüentemente identificados. Foram caracterizadas três amostras com misturas de sorotipos. As amostras positivas e mais 163 amostras, coletadas em um laboratório particular, em 2000, foram genotipadas. Os genótipos G2P[4] e G1P[8] foram os mais freqüentes nos anos de 1994-1996 e G1P[8] e G9P[8], os mais freqüentes em 2000. Os genótipos G3 e G4 foram detectado em menor freqüência. No HU, 20 (38,5%) amostras foram caracterizadas como misturas de genótipos G e 16 (29,6%), como misturas de genótipos P; não foram identificadas misturas em 2000. Dezoito amostras foram caracterizadas como P[10] por RT-PCR mas a análise da seqüência de nucleotídeos mostrou uma homologia de 90,7 a 98,0% com a amostra padrão P[8]. / From 187 fecal samples collected from outpatients at Hospital Universitário (HU)/ USP, between 1994 to 1996, 54 (28,9%) were positive for rotavirus. Positive samples were submitted to electropherotyping, subgrouping, and G serotype. Electropherotypes were characterized as nine different long genome profiles, one short and one unusual profile. Subgroup II and G2 serotype were the most frequently found and three samples showed mixed serotypes. Rotavirus samples and an additional 163 positive fecal samples, collected in a private laboratory in 2000, were G and P genotyped. Genotypes G2P[4] and G1P[8] were the most frequently found in 1994-1996 and, in 2000, G1P[8] and G9P[8] were the most frequent. Genotype G3 and G4 were detected as minor strains in both years. For HU, G genotype mixtures were found in 20 (38.5%) samples and P mixtures were found in 16 (29.6%). No mixtures were identified in 2000. Nucleotide sequencing and phylogenetic analysis of 18 P[10] samples by RT-PCR showed 90.7 to 98.0% homology with the P[8] prototype.
164

Structural Studies On The Rotaviral Enterotoxin NSP4

Chacko, Anita Rachel 06 1900 (has links) (PDF)
No description available.
165

Proporção de rotavírus, norovírus e Cryptosporidium ssp. em crianças com diarreia aguda atendidas no Hospital de Urgências de Sergipe / Proportion of rotavirus, norovirus and Cryptosporidium spp. in children with acute diarrhea treated at Sergipe Emergency Hospital

Vicente, Ana Paula Constantino do Amaral 30 August 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Acute diarrhea is one of the most common infectious diseases and still one of the leading causes of morbidity and mortality in the pediatric world, a global public health problem. Several efforts have been made over the years to reduce infant mortality, despite the commitment of diarrhea still occupy a significant space of malnutrition in children under 5 years. A wide spectrum of enteric pathogens can cause acute childhood diarrhea, among which we can mention Rotavirus, Norovirus and Cryptosporidium spp. Rotavirus is one of the most important. Currently two live attenuated live Rotavirus vaccines have been licensed and are available globally: a human monovalent strain (RV1) (Rotarix®, GlaxoSmithKline Biologicals) and a pentavalent bovine-human rearrangement (RV5) (Rotateq®). Brazil was one of the first countries to integrate the vaccine into its national immunization program (2006), and it was possible to observe significant improvements in reducing infant mortality and hospitalizations for diarrheal diseases in children from Rotavirus. However, diarrhea continues to be a serious health problem, and can be avoidable and treatable. Several etiological agents may be related to these intestinal infections and deserve to be investigated. The objective of this study was to verify the presence of the three etiological agents Cryptosporidium spp., Rotavirus and Norovirus, associated with diarrhea in children aged 0 to 11 years old, attended at Sergipe Emergency Hospital (HUSE). The samples were tested by Elisa for Cryptosporidium spp and Rotavirus for fecal antigen detection and reverse transcription polymerase chain reaction (RT-PCR) for Norovirus detection. A total of 92 diarrheic stool specimens were analyzed, of which 62% were positive for one of the pathogens studied, 49% positive for Norovirus, 10% for Rotavirus, 4% for Crysptoporidium spp and 37% of diarrheal samples were not positive for any enteropathogen studied. Norovirus was the main cause of childhood diarrhea in the period studied, with predominance (98%) of the GII genotype. The most affected age group were children younger than 24 months. Infections have shown similar symptoms. Complementary studies are needed to discover other etiological agents involved in gastroenteritis in the State of Sergipe, since a significant number of children with diarrhea did not present positivity to any of the pathogens studied. / A diarreia aguda é uma das doenças infecciosas mais comuns e ainda uma das principais causas de morbidade e mortalidade no mundo pediátrico, um problema global de saúde pública. Diversos esforços vêm sendo realizados no decorrer dos anos para redução da mortalidade infantil, apesar do empenho as diarreias ainda ocupam um significativo espaço da desnutrição em menores de 5 anos. Um amplo espectro de patógenos entéricos pode provocar a diarreia infantil aguda, dentre esses podemos citar os Rotavírus, Norovírus e Cryptosporidium spp, sendo o Rotavírus um dos mais importantes. Atualmente duas vacinas orais contra o Rotavírus, de vírus vivos atenuados foram licenciadas e estão disponíveis globalmente: uma cepa monovalente humana (RV1) (Rotarix®, GlaxoSmithKline Biologicals) e um rearranjo bovino-humano pentavalente (RV5) (Rotateq®). O Brasil foi um dos primeiros países a integrar a vacina em seu programa nacional de imunizações (2006), e foi possível observar melhorias significativas na redução da mortalidade infantil e nas hospitalizações por doenças diarreicas em crianças decorrentes de Rotavírus. No entanto, as diarreias continuam sendo um grave problema de saúde, podendo ser evitável e tratável. Diversos agentes etiológicos podem estar relacionados a essas infecções intestinais e merecem ser investigados. O objetivo desse estudo foi verificar a presença dos três agentes etiológicos Cryptosporidium spp., Rotavírus e Norovírus, associados aos quadros de diarreia aguda em crianças de 0 a 11 anos atendidas no Hospital de Urgência de Sergipe (HUSE). As amostras foram testadas por Elisa para Cryptosporidium spp e Rotavírus, para detecção de antígenos nas fezes, e reação de cadeia em polimerase após transcrição reversa (RT-PCR) para detecção de Norovírus. Foram analisadas 92 amostras de fezes diarreicas das quais 62% apresentaram positividade para um dos patógenos estudados, 49% positivos para Norovírus, 10% para Rotavírus, 4% para Crysptoporidium spp e 37% das amostras diarreicas não apresentaram positividade para nenhum enteropatógeno estudado. Norovírus foi o principal causador da diarreia infantil no período estudado, com predominância (98%) do genótipo GII. A faixa etária mais acometida foi de crianças menores de 24 meses. As infecções demonstraram sintomas semelhantes. Estudos complementares são necessários para descobrir outros agentes etiológicos envolvidos em gastroenterites do Estado de Sergipe, visto que uma quantidade significativa de crianças com diarreia não apresentou positividade para nenhum patógeno estudado. / São Cristóvão, SE
166

Avaliação da ação neutralizante e da reatividade de anticorpos IgA e IgG anti-rotavírus SA-11 em soro de adultos saudáveis. / Evaluation of neutralizing ability and reactivity of anti-rotavirus SA-11 IgA and IgG antibodies in serum samples from healthy adults.

Thalita Lopes Ferreira 17 May 2011 (has links)
O rotavírus é a principal causa de diarréia em crianças em todo o mundo. Infecta também adultos, mas não há dados completos sobre a sua incidência nesse grupo nem sobre o papel de anticorpos preexistentes na proteção contra o vírus. O objetivo do trabalho foi avaliar a presença de anticorpos IgA e IgG anti-rotavírus SA-11, por ELISA, em amostras de soro de adultos saudáveis e sua ação neutralizante frente ao vírus, em ensaios de neutralização. Por Immunoblotting foi avaliado o reconhecimento de proteínas virais pelos anticorpos séricos. Observou-se que os títulos das amostras foram muito variáveis, sendo os de IgG superiores aos de IgA. Todas as amostras mostraram-se capazes de neutralizar o vírus em diferentes níveis, porém não foi possível estabelecer uma correlação com os títulos de anticorpos. Foi observado que anticorpos da classe IgG reconhecem mais proteínas virais que os da classe IgA. Este trabalho pode ser considerado mais um passo na elucidação do papel dos anticorpos séricos IgA e IgG anti-rotavírus na infecção em adultos. / Rotavirus has been considered the leading cause of diarrhea in children worldwide. The virus also infects adults but there is no conclusive data neither on the incidence of infection on this group nor on the role of pre-existing antibodies. The aim of the work was to evaluate the presence of anti-rotavirus SA-11 IgA and IgG by ELISA in serum samples of healthy adults and the serum neutralizing ability against the virus by neutralization assays. Immunoblotting was used to evaluate viral proteins recognition by serum antibodies. The antibody titers were extremely variable where IgG titers are greater than IgA ones. All samples were able to neutralize the virus in different levels but it was not possible to establish a correlation between antibody titers and neutralization ones. Immunoblotting assays revealed that IgG antibodies recognize more viral proteins than IgA did. This work can be considered a valuable step for elucidating the role of serum anti-rotavirus IgG and IgA antibodies in adults infection.
167

Transferência de imunidade passiva de vacas da raça Holandesa imunizadas e não imunizadas contra rotavírus para seus bezerros /

Rocha, Thaís Gomes. January 2013 (has links)
Orientador: José Jurandir Fagliari / Coorientador: Maria da Glória Buzinaro / Coorientador: Luiz Francisco Zafalon / Banca: Luis Guilherme de Oliveira / Banca: Annelise Carla Camplesi dos Santos / Banca: Viviani Gomes / Banca: Raimundo Souza Lopes / Resumo: O objetivo do presente estudo foi avaliar a resposta imune humoral de vacas primíparas e pluríparas imunizadas ou não contra rotavírus com vacina comercial inativada e a transferência dessa imunidade para seus bezerros. Para tal, ensaio imunoenzimático indireto (EIE indireto) foi utilizado, sendo constituídos dois grupos e quatro subgrupos experimentais: grupo V1: 24 vacas imunizadas contra rotavírus bovino (BRV), com dois subgrupos - V1n (12 vacas primíparas) e V1v (12 vacas pluríparas) e grupo V2: 24 vacas não imunizadas contra BRV, com dois subgrupos - V2n (12 vacas primíparas) e V2v (12 vacas pluríparas). Os bezerros também foram alocados em grupos e subgrupos, de acordo com a distribuição de suas mães para a avaliação da imunidade humoral sérica, da cinética de parâmetros hematológicos, bioquímicos e da excreção de rotavírus nas fezes nos trinta primeiros dias de vida. Os bezerros foram ainda realocados, de acordo com a ocorrência de diarreia no primeiro mês de vida, sendo constituídos os grupos A (sem diarreia), B (diarreia, negativos para a detecção de rotavírus) e C (diarreia, positivos para rotavírus). Os dados foram submetidos à análise de variância, e o teste de Tukey e o teste de correlação de Pearson foram empregados, considerando-se as diferenças significativas quando P<0,05. Nas vacas dos grupos V1 e V2, não foi verificada influência do número de parições sobre os parâmetros séricos analisados, enquanto que na análise do colostro, verificou-se maiores teores de IgA e IgG em vacas do subgrupo V1v. A imunização pré-parto aumentou significativamente os títulos séricos de IgG anti-BRV, sendo os maiores títulos verificados também nos animais do subgrupo V1v. Os bezerros que receberam colostro dessas vacas (grupo B1) também apresentaram maiores títulos de IgG anti-BRV, quando comparados ao grupo B2, no entanto, a vacinação da vaca ... / Abstract: The aim of this study was to evaluate the humoral immune response of primiparous and multiparous cows immunized with an inactivated commercial vaccine against rotavirus, as well as the passive immunity transfer to its calves through indirect enzymatic immunoassay (EIE); thus, two groups and four subgroups were formed: Group V1: 24 cows immunized with a commercial inactivated vaccine against BRV, comprising two subgroups - V1n (12 first gestation cows) and V1v (12 second or later gestation cows) and Group V2: 24 cows not immunized against BRV, comprising two subgroups - V2n (12 first gestation cows) and V2v (12 second or later gestation cows). The calves were also allotted into groups and subgroups according to its mother's distribution, in order to evaluate humoral immune response in serum, the kinetics of hematological and biochemical parameters, the acute phase proteins response, and rotavirus excretion in feces throughout the first 30 days of life. The same calves were also redistributed into groups according to the occurrence of diarrhea in the first month of life as Group A (no diarrhea), group B (diarrhea, but negative to rotavirus detection) and group C (diarrhea, positive to rotavirus detection). Data were submitted to variance analysis and Tukey's test was performed in order to compare mean values of parameters and establish differences between groups; differences were considered significant when P<0,05. Pearson's correlation test was also performed in some of the studied parameters, and was considered significant when P<0,05. In group V1 and V2 cows, there was no influence of lactation number in the serum parameters analyzed, whilst in the colostrum whey, higher levels of IgA and IgG were noted in V1v cows when compared to the other Subgroups. Prepartum immunization of cows with a commercial vaccine against rotavirus effectively raised titers of specific IgG against rotavirus ... / Doutor
168

Porcine Intestinal Enteroids: A Novel Model to Study Host Glycan-Rotavirus Interaction

Guo, Yusheng January 2021 (has links)
No description available.
169

Assessment and Control of Virological Risk in Reclaimed Water Treated by Soil Aquifer Treatment / 土壌浸透処理を介した再生水飲用に伴う病原ウイルスの感染リスク評価

Thuangsit, Denpetkul 23 September 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19983号 / 工博第4227号 / 新制||工||1654(附属図書館) / 33079 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 伊藤 禎彦, 教授 米田 稔, 准教授 西村 文武 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
170

Entwicklung einer Reversen Transkription-Polymerase-Kettenreaktion (RT-PCR) zum Nachweis der Persistenz von Rotaviren beim Schwein

Schwarz, Bernd-Andreas 05 September 2003 (has links)
Im Graduiertenkolleg „Schlachttierbelastung und Produktsicherheit“ der Veterinärmedizinischen Fakultät der Universität Leipzig sollten in interdisziplinärer Zusammenarbeit Erkenntnisse zum Verhalten transportbelasteter Schlachtschweine in Bezug auf bakterielle Translokationsprozesse erarbeitet werden. Es wurden Mastschweine aus herkömmlichen Mastbetrieben definierten Belastungssituationen ausgesetzt , geschlachtet und untersucht. Dabei sollten physiologische, pathologisch-anatomische, immunologische, lebensmittel- und fleischhygienische, bakteriologische, virologische sowie ethologische Fragestellungen bearbeitet werden. Ziel war es festzustellen, ob eine Belastung der Tiere (u.a. durch den Transport) Auswirkungen auf die Produktqualität hat und ob durch eine Translokation pathogener Erreger ein Risiko für die Gesundheit des Verbrauchers besteht. Im Teilprojekt des Institutes für Virologie wurde untersucht, ob Rotavirus-Infektionen von Schlachtschweinen unter der Problematik der Belastung ein mögliches Infektionsrisiko für den Menschen darstellen. Um die zu erwartende niedrige Konzentration von Rotaviren in Organen von Schlachtschweinen nachweisen zu können, wurde eine kompetitive RT-PCR zum Nachweis von Rotaviren der Gruppe A verschiedener Spezies entwickelt. Dazu wurde ein sogenannter Kompetitor synthetisch hergestellt, welcher als interne oder externe Reaktionskontrolle eingesetzt wurde. Zum einen diente er der Überprüfung des ordnungsgemäßen Verlaufes einer RT-PCR, zum anderen wurde er zur Herstellung von Standards verwendet. Die RT-PCR wurde anschließend in eine „Real time“ RT-PCR umgewandelt. Sowohl mit der herkömmlichen als auch mit der „Real-time“ RT-PCR konnten 10 spezifische RNA-Moleküle in einer Probe nachgewiesen werden. In einer SPF-Schweineherde, welche einer Belastung infolge eines Tiertransports ausgesetzt war, konnten mit Hilfe der RT-PCR klinisch gesunde intermittierende Rotavirus-Ausscheider entdeckt werden. Bei einigen dieser Tiere gelang der Nachweis der Virusausscheidung über einen Zeitraum von drei Monaten. Nach der Schlachtung wurden in Organen des lymphatischen Systems bei zwei Schweinen sehr geringe Konzentrationen an rotavirus-spezifischer RNA detektiert. Infektiöses Virus konnte daraus allerdings nicht isoliert werden. Auch in einer Mastschweineherde konnte bei einigen Tieren Rotavirus-spezifische RNA im Kot nachgewiesen werden. Ein Infektionsversuch dieser Tiere mit Salmonella typhimurium konnte keine Reaktivierung der Rotavirus-Infektion auslösen. Aufgrund des Zoonose-Potentials von Rotaviren kann nach den Untersuchungen ein Infektionsrisiko für den Verbraucher durch eine endogene Kontamination von Schlachttieren mit Rotaviren nicht sicher ausgeschlossen werden. Die Untersuchungen zeigten auch, dass intermittierende Rotavirus-Ausscheider ein Infektionsrisiko für den Verbraucher darstellen, wenn z.B. bei der Schlachtung der Tiere oder bei der Verarbeitung des Fleisches dieser Tiere hygienische Grundregeln verletzt werden. Besonders gefährdet wären hierbei Neugeborene, Kinder, Senioren und immunsupprimierte Personen. Ein Ort einer Viruspersistenz in Organen konnte auch nach diesen Untersuchungen nicht gefunden werden. Dennoch scheint es, dass Rotaviren in der Natur oder in einer Population von Menschen oder Tieren persistieren. Durch ständige Neuinfektionen bzw. Reinfektionen empfänglicher Organismen haben Rotaviren so ihre Erhaltung gesichert. / Within the graduate programme “Schlachttierbelastung und Produktsicherheit” of the Veterinary Faculty of the University of Leipzig, the behaviour of slaughter swine exposed to the stress of transport was observed in an interdisciplinary collaboration concerning the translocation processes of bacteria. Fattened pigs from conventional pig fattening units were exposed to particular stress situations, and then slaughtered and examined. The following aspects of this process were investigated: physiology, pathological-anatomy, immunology, food and meat hygiene, bacteriology, virology and ethology. The aim of this study was to verify whether exposing the animals to stress situations (such as transport) influences the quality of the product and whether the translocation of pathogens represents a risk for consumer health. Within the sub-project of the Institute for Virology, analyses were made to verify whether rotavirus infections of slaughter swine exposed to stress situations represents a potential contamination risk for humans. In order to detect the expected low concentration of rotaviruses in the organs of slaughtered pigs, a competitive RT-PCR was developed as a test of rotaviruses for various group A species. To do this, a so-called competitor was synthetically created, which was used as an internal and external reaction control. On one hand, it was used to verify the regular course of an RT-PCR reaction, and on the other hand, it was implemented to develop standards. RT-PCR was then modified by means of a real time RT-PCR. Both with the conventional and with the real time RT-PCR, it was possible to detect 10 specific RNA molecules/ sample.With this new very sensitive and specific amplification process, it was possible to detect rotavirus-specific RNA in the excrement of people and of pigs, cows, horses, rabbits and monkeys. the evidence of the virus excretion was produced over a time period of three months. After slaughtering, low amounts of rotavirus specific RNA were found in the organs of the lymphatic system. There were no indications that any of these organs were infectious. Rotavirus specific RNA was also found in the excrement of some fattened pigs. An attempt to infect these animals with Salmonella typhimurium was unable to cause any reactivation of the rotavirus infection. An infection risk for the consumer through an endogenous rotavirus contamination of fattened pigs cannot be excluded with any degree of certainty on the basis of these analyses due to the zoonotic potential of rotaviruses. The analyses also showed that intermittent rotavirus excretors represent an infection risk for the consumer, if for example basic hygiene rules are broken during the slaughter or meat processing of these animals. At special risk may be new-borns, children, youth, the elderly and people suffering from immunodeficiency. These examinations could not find a specific place in the organs where the virus persists. Nevertheless, it seems that rotaviruses persist in the environment or in a population of people or animals. With constant new infections or re-infections of receptive organisms, rotaviruses seem to have assured their survival.

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