No Brasil, casos de doença exantemática em bovinos e humanos têm sido relatados em diversas regiões, cujo agente causal é o virus vaccinia pertencente ao gênero Orthopoxirus da família Poxviridae. Classicamente, a varíola bovina é causada pelo Cowpoxvirus, entretanto, outros Poxvirus, como o vírus vaccinia podem desenvolver sintomatologia clínica semelhante. Além de comprometer a cadeia produtiva de leite, uma vez que dificulta a ordenha, predispõe a mastite e descarte do produto, é uma zoonose e atualmente está incluída no diagnóstico de doença vesicular. A origem desses casos bem como a epidemiologia da doença ainda é pouco conhecida. Assim, objetivou-se no presente estudo 1) Avaliar a soroprevalência de Orthopoxirus em rebanhos bovinos do circuito sete do Estado de São Paulo que compreendem as regiões do Vale do Paraíba e Mogi das Cruzes e associar os possíveis fatores de risco envolvidos na transmissão da doença; 2) Detectar e caracterizar a presença de Orthopoxirus em amostras suspeitas de doença vesicular, no período de 2007 a 2009, provenientes de diversas regiões do Brasil utilizando técnicas convencionais e moleculares: microscopia eletrônica, isolamento viral, PCR e RFLP; 3) Sequenciamento e análise filogenética das amostras positivas para o vírus vaccinia. Para o inquérito soroepidemiológico foram analisadas 76 propriedades pertencentes ao circuito 7 que compreendem as regiões do Vale do Paraíba e Mogi das Cruzes, estado de São Paulo, selecionadas aleatoriamente, totalizando 619 animais, estratificados em fêmeas acima de dois anos. A soroprevalência de Orthopoxirus no Vale do Paraíba foi de 32,3% (200/619) pela virusneutralização. Associação positiva foi encontrada para presença de animais silvestres. No diagnóstico virológico foram analisadas 227 amostras de epitélio, negativas para outras doenças vesiculares. Encontrou-se frequencia de 63,4% (144/227) positivas para o Orthopoxirus em praticamente todas as regiões do país. A análise por RFLP revelou perfil de padrão para o vírus vaccinia. O sequenciamento dos isolados confirmou que o vírus vaccinia é a estirpe circulante e está agrupado no grupo I de isolados de vaccinia brasileiros. / In Brazil, cases of rash illness in cattle and humans have been reported in several regions whose causal agent is the vaccinia virus belonging to the genus Orthopoxirus (OPV) family Poxviridae. Classically, cowpox is caused by Cowpoxvirus, however, other poxviruses such as vaccinia virus may develop same clinical signs. In addition to compromising the production chain of milk, as it hampers milking, predisposes to mastitis and discard the product, also it is a zoonosis and is currently included in the differential diagnosis of vesicular disease. The origin of these cases as well as the epidemiology of the disease is still unknown. Thus, the aim of the present study 1) assess the serum prevalence of OPV in cattle herds circuit seven Vale do Paraíba and associate the possible risk factors involved in disease transmission, 2) identify and characterize the presence of OPV in samples suspected vesicular disease in the period 2007-2009, from various regions of Brazil using conventional techniques and molecular electron microscopy, virus isolation, PCR and RFLP; 3) Sequencing and phylogenetic analysis of the samples positive for OPV. For epidemiological survey were analyzed 76 properties in the region of Vale do Paraíba, São Paulo, randomly selected, totaling 619 animals, stratified in females more than two years. The serum prevalence of OPV in the Paraíba Valley was 32.3% (200/619) by virus neutralization. Positive association was found for presence of wild animals. The virological diagnosis were analyzed 227 samples of epithelium, negative for other vesicular diseases. Met frequency of 63.4% (144/227) positive for OPV in practically all regions of the country. RFLP analysis revealed default profile for the vaccinia virus. The sequencing of the isolates confirmed that vaccinia virus strain is circulating and is clustered in group I isolates of Brazilians vaccinia.

Resumo: O Vírus da Diarréia Viral Bovina (BVDV) é um dos patógenos mais importantes na pecuária bovina em todo mundo, principalmente por desencadear manifestações clínicas relacionadas à esfera reprodutiva. A infecção em fêmeas gestantes pode resultar em abortamentos, reabsorções embrionárias, mumificações fetais, má formações e nascimento de bezerros fracos além do aparecimento de animais persistentemente infectados e imunotolerantes ao vírus, que são a principal fonte de infecção e disseminação da doença nos rebanhos. Atualmente, a complexidade do diagnóstico e consequentemente a patogenia, estão relacionados às diferenças genotípicas do agente. Por isso, a presente pesquisa teve como objetivo verificar a ocorrência dos genótipos BVDV-1 (Singer) e BVDV-2 (VS-253) em vacas, e respectivos fetos, abatidas em um frigorífico no Estado de São Paulo por meio da análise do soro sanguineo por meio da técnica de virusneutralização. No contexto geral, 52,51% (115/219) das vacas testadas foram reagentes, mas nenhum feto (0/219) reagiu na virusneutralização. Pela análise cruzada conforme a estirpe viral, observou-se que 42% (92/219) das vacas foram reagentes tanto para o genótipo BVDV-1 como para o genótipo do BVDV-2. Por outro lado 4,10% (9/219) reagiram apenas para o genótipo BVDV-1 e 6,39% (14/219) reagiram apenas para o genótipo do BVDV 2. Notou-se portanto que ambas as estirpes estão disseminadas nas regiões estudadas, fato que justifica o emprego de antígenos diferentes para evitar diagnóstico falso-negativo. Por fim, não foi observado qualquer alteração nos fetos que pudessem ser caracterizada como patologia da enfermidade. / Abstract: The Bovine viral diarrhea virus (BVDV) is one of the pathogens in bovine livestock worldwide most important mainly triggered by clinical manifestations related to the reproductive sphere. The infection in pregnant females may result in abortions, embryonic resorptions, fetal mummification, poor training, birth of weak calves in addition to persistently infected and virus immunotolerant animals, which are the main source of infection and spread of the disease. Currently, the complexity to diagnosis and consequently to the pathogenesis are related genotypic differences that he presents. Therefore, this research aimed to verify the occurrence of BVDV- 1 (Singer) and BVDV-2 (VS-253) genotypes in cows and their respective fetuses slaughtered in a abattoir at the state of São Paulo by analyzing the blood serum using virusneutralization technique. In the general context, 52.51% (115/219) of cows were reagents, but no fetus (0/219) reacted in virusneutralization. After a cross-examination we observed that 42% (92/219) of cows reacted for both BVDV-1 and BVDV-2 genotype. Furthermore 4,10% (9/219) reacted only to the genotype BVDV-1 and 6,39% (14/219) responded only to the genotype 2 of BVDV. It was noted therefore that both strains are widespread in the regions studied, which also justifies the use of different antigens to avoid false-negative diagnosis. Finally, there was no change in fetuses that could be characterized as a pathology of the disease. / Orientador: Samir Issa Samara / Coorientador: Fabio Carvalho Dias / Banca: José Gabriel Amoril / Banca: Sandra Possebon Gatti / Mestre

No Brasil, casos de doença exantemática em bovinos e humanos têm sido relatados em diversas regiões, cujo agente causal é o virus vaccinia pertencente ao gênero Orthopoxirus da família Poxviridae. Classicamente, a varíola bovina é causada pelo Cowpoxvirus, entretanto, outros Poxvirus, como o vírus vaccinia podem desenvolver sintomatologia clínica semelhante. Além de comprometer a cadeia produtiva de leite, uma vez que dificulta a ordenha, predispõe a mastite e descarte do produto, é uma zoonose e atualmente está incluída no diagnóstico de doença vesicular. A origem desses casos bem como a epidemiologia da doença ainda é pouco conhecida. Assim, objetivou-se no presente estudo 1) Avaliar a soroprevalência de Orthopoxirus em rebanhos bovinos do circuito sete do Estado de São Paulo que compreendem as regiões do Vale do Paraíba e Mogi das Cruzes e associar os possíveis fatores de risco envolvidos na transmissão da doença; 2) Detectar e caracterizar a presença de Orthopoxirus em amostras suspeitas de doença vesicular, no período de 2007 a 2009, provenientes de diversas regiões do Brasil utilizando técnicas convencionais e moleculares: microscopia eletrônica, isolamento viral, PCR e RFLP; 3) Sequenciamento e análise filogenética das amostras positivas para o vírus vaccinia. Para o inquérito soroepidemiológico foram analisadas 76 propriedades pertencentes ao circuito 7 que compreendem as regiões do Vale do Paraíba e Mogi das Cruzes, estado de São Paulo, selecionadas aleatoriamente, totalizando 619 animais, estratificados em fêmeas acima de dois anos. A soroprevalência de Orthopoxirus no Vale do Paraíba foi de 32,3% (200/619) pela virusneutralização. Associação positiva foi encontrada para presença de animais silvestres. No diagnóstico virológico foram analisadas 227 amostras de epitélio, negativas para outras doenças vesiculares. Encontrou-se frequencia de 63,4% (144/227) positivas para o Orthopoxirus em praticamente todas as regiões do país. A análise por RFLP revelou perfil de padrão para o vírus vaccinia. O sequenciamento dos isolados confirmou que o vírus vaccinia é a estirpe circulante e está agrupado no grupo I de isolados de vaccinia brasileiros. / In Brazil, cases of rash illness in cattle and humans have been reported in several regions whose causal agent is the vaccinia virus belonging to the genus Orthopoxirus (OPV) family Poxviridae. Classically, cowpox is caused by Cowpoxvirus, however, other poxviruses such as vaccinia virus may develop same clinical signs. In addition to compromising the production chain of milk, as it hampers milking, predisposes to mastitis and discard the product, also it is a zoonosis and is currently included in the differential diagnosis of vesicular disease. The origin of these cases as well as the epidemiology of the disease is still unknown. Thus, the aim of the present study 1) assess the serum prevalence of OPV in cattle herds circuit seven Vale do Paraíba and associate the possible risk factors involved in disease transmission, 2) identify and characterize the presence of OPV in samples suspected vesicular disease in the period 2007-2009, from various regions of Brazil using conventional techniques and molecular electron microscopy, virus isolation, PCR and RFLP; 3) Sequencing and phylogenetic analysis of the samples positive for OPV. For epidemiological survey were analyzed 76 properties in the region of Vale do Paraíba, São Paulo, randomly selected, totaling 619 animals, stratified in females more than two years. The serum prevalence of OPV in the Paraíba Valley was 32.3% (200/619) by virus neutralization. Positive association was found for presence of wild animals. The virological diagnosis were analyzed 227 samples of epithelium, negative for other vesicular diseases. Met frequency of 63.4% (144/227) positive for OPV in practically all regions of the country. RFLP analysis revealed default profile for the vaccinia virus. The sequencing of the isolates confirmed that vaccinia virus strain is circulating and is clustered in group I isolates of Brazilians vaccinia.

Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Canine herpesvirus type 1 (CHV-1) is associated with reproductive disorders and neonatal mortality. CHV-1 is widely distributed and is considered enzootic in the dog population. Occurrence of infection in the country is unknown, and thus the real need for additional prevention measures, such as vaccination, is unknown. Therefore, the aim of this study was to investigate the presence of antibodies against CHV-1 in serum samples of domestic and sheltered dogs of different regions from Rio Grande do Sul state. For this, 914 serum samples from domestic dogs from Santa Maria (332 dogs obtained from Hospital Veterinário Universitário - HVU / UFSM and 381 from in the anti-rabies vaccination campaign), a veterinary clinical laboratory in Porto Alegre (n=43) and 158 from shelters dogs of Passo Fundo (n=98) and Cachoeira do Sul (n=60). Serum samples were tested by virus-neutralization test (VN) for CHV-1 antibodies. Neutralizing antibodies against CHV-1 in titers equal or higher than 4 were detected in 66,9% (612/914) of the samples. Among household dogs, 79,5% (264/332) from HVU/UFSM and 57.2% (218/381) from the vaccination campaign. Among the samples collected in the clinical laboratory in Porto Alegre, 41.8% (18/43) had antibodies to CHV-1. Among the sheltered dogs, 72.4% (71/98) of samples from Passo Fundo and 68.3% (41/60) from Cachoeira do Sul had antibody to CHV-1. The antibody titers ranged among the groups, but many samples had titers higher than 128. Since there are no commercial vaccines against CHV-1 in Brazil, the presence of neutralizing antibodies indicates the circulation of CHV-1 in the investigated population. Based on these findings, control measures, prevention, immunization and the need for a correct diagnosis should be considered. / O herpesvírus canino tipo 1 (CHV-1) está associado a desordens reprodutivas e mortalidade neonatal em cães. O CHV-1 tem distribuição mundial e é considerado enzoótico na população canina, no entanto, a frequência da infecção no país ainda é desconhecida, e assim, se desconhece a real necessidade de medidas adicionais de prevenção, como a vacinação. Com isso, o objetivo deste trabalho foi investigar a presença de anticorpos contra o CHV-1 em amostras de soro de cães domiciliados e de abrigos em diferentes cidades do Rio Grande do Sul. Para isso, foram testadas 914 amostras de soro de cães domiciliados de Santa Maria (332 amostras obtidas do Hospital Veterinário Universitário - HVU/UFSM e 381 obtidas durante a campanha de vacinação antirrábica de 2015), de um laboratório clínico veterinário de Porto Alegre (n=43) e 158 de cães de abrigos dos municípios de Passo Fundo (n=98) e Cachoeira do Sul (n=60). Estas amostras de soro foram testadas pela técnica de soroneutralização (SN) para anticorpos contra o CHV-1. Anticorpos neutralizantes contra o CHV-1, em títulos iguais ou superiores a 4, foram detectados em 66,9% (612/914) das amostras. Entre os cães domiciliados de Santa Maria, 79,5% (264/332) provenientes do HVU/UFSM e 57,2% (218/381) das obtidas durante a campanha de vacinação antirrábica de Santa Maria foram positivas. Das amostras coletadas no laboratório clínico em Porto Alegre, 41,8% (18/43) foram positivas para anticorpos para CHV-1. Entre os cães de abrigo, 72,4% (71/98) das amostras coletadas em Passo Fundo e 68,3% (41/60) das amostras do abrigo de Cachoeira do Sul foram sorologicamente positivas para CHV-1. Os títulos de anticorpos entre os grupos foram variáveis, mas a maioria dos animais positivos possuía títulos acima de 128. Como não existem vacinas comerciais contra o CHV-1 no Brasil, a presença de anticorpos neutralizantes indica a circulação do CHV-1 na população canina das cidades estudadas. Com base nesses achados, medidas de controle, prevenção, imunização e a necessidade de um correto diagnóstico devem ser consideradas contra o CHV-1 em cães no sul do Brasil.

Re-vaccinations against canine distemper virus (CDV) are commonly performed in 3-year intervals. The study’s aims were to determine anti-CDV antibodies in healthy adult dogs within 28 days of vaccination against CDV, and to evaluate factors associated with the presence of pre-vaccination antibodies and with the antibody response to vaccination. Ninety-seven dogs, not vaccinated within 1 year before enrollment, were vaccinated with a modified live CDV vaccine. A measurement of the antibodies was performed before vaccination (day 0), on day 7, and 28 after the vaccination by virus neutralization. A response to vaccination was defined as a ≥4-fold titer increase by day 28. Fisher’s exact test was used to determine factors associated with a lack of antibodies and vaccination response. In total, 94.8% of the dogs (92/97; CI 95%: 88.2–98.1) had antibodies (≥10) prior to vaccination. A response to vaccination was not observed in any dog. Five dogs were considered humoral non-responders; these dogs neither had detectable antibodies before, nor developed antibodies after vaccination. Young age (<2 years) was significantly associated with a lack of pre-vaccination antibodies (p = 0.018; OR: 26.825; 95% CI: 1.216–1763.417). In conclusion, necessity of re-vaccination in adult healthy dogs should be debated and regular vaccinations should be replaced by antibody detection.

Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-16Bitstream added on 2014-06-13T19:26:13Z : No. of bitstreams: 1 oliveira_mc_me_jabo.pdf: 308908 bytes, checksum: 64bbc47e580df30ef60b342b4c429d6c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Vírus da Diarréia Viral Bovina (BVDV) é um dos patógenos mais importantes na pecuária bovina em todo mundo, principalmente por desencadear manifestações clínicas relacionadas à esfera reprodutiva. A infecção em fêmeas gestantes pode resultar em abortamentos, reabsorções embrionárias, mumificações fetais, má formações e nascimento de bezerros fracos além do aparecimento de animais persistentemente infectados e imunotolerantes ao vírus, que são a principal fonte de infecção e disseminação da doença nos rebanhos. Atualmente, a complexidade do diagnóstico e consequentemente a patogenia, estão relacionados às diferenças genotípicas do agente. Por isso, a presente pesquisa teve como objetivo verificar a ocorrência dos genótipos BVDV-1 (Singer) e BVDV-2 (VS-253) em vacas, e respectivos fetos, abatidas em um frigorífico no Estado de São Paulo por meio da análise do soro sanguineo por meio da técnica de virusneutralização. No contexto geral, 52,51% (115/219) das vacas testadas foram reagentes, mas nenhum feto (0/219) reagiu na virusneutralização. Pela análise cruzada conforme a estirpe viral, observou-se que 42% (92/219) das vacas foram reagentes tanto para o genótipo BVDV-1 como para o genótipo do BVDV-2. Por outro lado 4,10% (9/219) reagiram apenas para o genótipo BVDV-1 e 6,39% (14/219) reagiram apenas para o genótipo do BVDV 2. Notou-se portanto que ambas as estirpes estão disseminadas nas regiões estudadas, fato que justifica o emprego de antígenos diferentes para evitar diagnóstico falso-negativo. Por fim, não foi observado qualquer alteração nos fetos que pudessem ser caracterizada como patologia da enfermidade. / The Bovine viral diarrhea virus (BVDV) is one of the pathogens in bovine livestock worldwide most important mainly triggered by clinical manifestations related to the reproductive sphere. The infection in pregnant females may result in abortions, embryonic resorptions, fetal mummification, poor training, birth of weak calves in addition to persistently infected and virus immunotolerant animals, which are the main source of infection and spread of the disease. Currently, the complexity to diagnosis and consequently to the pathogenesis are related genotypic differences that he presents. Therefore, this research aimed to verify the occurrence of BVDV- 1 (Singer) and BVDV-2 (VS-253) genotypes in cows and their respective fetuses slaughtered in a abattoir at the state of São Paulo by analyzing the blood serum using virusneutralization technique. In the general context, 52.51% (115/219) of cows were reagents, but no fetus (0/219) reacted in virusneutralization. After a cross-examination we observed that 42% (92/219) of cows reacted for both BVDV-1 and BVDV-2 genotype. Furthermore 4,10% (9/219) reacted only to the genotype BVDV-1 and 6,39% (14/219) responded only to the genotype 2 of BVDV. It was noted therefore that both strains are widespread in the regions studied, which also justifies the use of different antigens to avoid false-negative diagnosis. Finally, there was no change in fetuses that could be characterized as a pathology of the disease.

Background: Re-vaccination against canine adenovirus (CAV) is performed in ≤3-year-intervals but its necessity is unknown. The study determined anti-CAV antibodies within 28 days of re-vaccination and factors associated with the absence of antibodies and vaccination response. Methods: Ninety-seven healthy adult dogs (last vaccination ≥12 months) were re-vaccinated with a modified live CAV-2 vaccine. Anti-CAV antibodies were measured before vaccination (day 0), and after re-vaccination (day 7, 28) by virus neutralization. A ≥4-fold titer increase was defined as vaccination response. Fisher’s exact test and multivariate regression analysis were performed to determine factors associated with the absence of antibodies and vaccination response. Results: Totally, 87% of dogs (90/97; 95% CI: 85.61–96.70) had anti-CAV antibodies (≥10) before re-vaccination. Vaccination response was observed in 6% of dogs (6/97; 95% CI: 2.60–13.11). Time since last vaccination (>3–5 years, OR = 9.375, p = 0.020; >5 years, OR = 25.000, p = 0.006) was associated with a lack of antibodies. Dogs from urban areas were more likely to respond to vaccination (p = 0.037). Conclusion: Many dogs had anti-CAV pre-vaccination antibodies, even those with an incomplete vaccination series. Most dogs did not respond to re-vaccination. Based on this study, dogs should be re-vaccinated every 3 years or antibodies should be determined.

Les phlébotomes sont les vecteurs reconnus de plusieurs arbovirus, en particulier du genre Phlebovirus, ainsi que de parasites du genre Leishmania. Les infections par les phlébovirus sont responsables chez l’homme de maladies décrites depuis longtemps, pourtant ils demeurent méconnus, avec en particulier un manque de données épidémiologiques et d’outils de diagnostic.Dans une première partie, des études de séroprévalence nous ont permis d’aborder l’impact en santé publique, dans le sud-est de la France, de deux phlébovirus connus pour leur pouvoir pathogène chez l’homme, Toscana virus (TOSV) et Sandfly fever Sicilian virus (SFSV). Pour ce dernier, des anticorps spécifiques (IgG) ont été détectés dans moins de 1% des sérums testés, ce qui suggère que SFSV joue un rôle mineur dans les pathologies humaines de cette région ; ces résultats sont corroborés par l’absence, durant ces dernières décennies, de cas documentés d’infection aigüe due à SFSV en Europe occidentale. Nous avons donc pu concentrer notre travail sur le deuxième groupe de phlébovirus d’intérêt chez l’homme, le groupe des Sandfly fever Naples virus, qui inclut notamment TOSV. Nous avons démontré l’existence d’un lien épidémiologique entre les infections à Leishmania infantum et celles à TOSV, certainement dû au fait que ces pathogènes sont transmis par un vecteur commun (Phlebotomus perniciosus). Les analyses statistiques ont montré que les personnes exposées aux infections à TOSV ont plus de chance d’être aussi infectées par les parasites leishmanies (et vice versa). En admettant que ce lien épidémiologique entre leishmanioses et infections à TOSV est représenté par l’exposition à la piqûre d’un vecteur commun, cette étude confirme l’implication de Phlebotomus perniciosus en tant que vecteur principal de TOSV dans le sud de la France. Cette étude suggère également que certaines données épidémiologiques disponibles pour la leishmaniose pourraient être utilisées pour décrypter l’épidémiologie des infections à TOSV.La deuxième partie de cette thèse est consacrée à la détection, l’isolement et la caractérisation de virus, déjà connus ou inconnus, dans les populations de phlébotomes en France et en Afrique du Nord. Pour atteindre cet objectif, nous avons dû développer une plateforme d’analyse à au débit, adaptée pour la découverte de virus dans les phlébotomes, qui permette de traiter un grand nombre d’échantillons à faible coût. Cette plateforme a récemment été complétée par un outil de Next Generation Sequencing, afin de réaliser la caractérisation génétique complète des virus isolés et découverts. Au total, 12 576 phlébotomes ont été capturés au cours de 12 campagnes de capture menées en France, en Tunisie et en Algérie. Au sein d’une même zone géographique, la découverte de plusieurs nouveaux phlébovirus, ainsi que leur taux d’infection observé dans les populations de phlébotomes, ont démontré que la diversité de phlebovirus est bien plus importante qu’attendue.Dans la troisième partie de cette thèse, une étude de séroprévalence a été menée sur des sérums humains en utilisant des tests comparatifs de neutralisation de virus. Cette étude nous a permis d’exclure le virus Punique, récemment découvert, de la liste des principales menaces en santé publique au nord de la Tunisie, et de confirmer que TOSV est le principal phlebovirus pathogène ayant un impact en santé publique dans cette région du pays. Cette méthode de neutralisation est capable d’identifier précisément, parmi des virus génétiquement proches, le virus contre lequel les anticorps présents dans le sang ont été produits, ce qui permet de déterminer la capacité de chacun de ces virus à jouer un rôle en santé publique. / Sandflies are vectors of various arthropod-borne viruses, in particular viruses within the genus Phlebovirus, family Bunyaviridae, and of parasites in the genus Leishmania. Human diseases caused by infection with sandfly-borne phleboviruses are known for a long time, but they remain neglected due to the lack of epidemiological knowledge and of diagnostic tools.The first part consisted of seroprevalence studies in human sera to address the public health impact in south-eastern France of two recognized sandfly-borne phleboviruses, namely Toscana virus (TOSV) and Sandfly fever Sicilian virus (SFSV). Concerning the latter, specific IgG were detected in less than 1% of tested sera, suggesting that SFSV play a minor role in human disease in the region; this finding was corroborated with the lack of documented case of acute infection due to SFSV in Western Europe during the last decade. This pleaded for focusing on the other group of sandfly fever viruses known for their human interest, namely the group of Sandfly fever Naples virus that includes TOSV. We demonstrated an existing epidemiological relationship between Leishmania infantum and TOSV infections, presumably through the transmission by the common arthropod vector (Phlebotomus perniciosus). Statistical analysis showed that persons exposed to TOSV infection are at greater risk of being infected with Leishmania parasite (and vice versa). Assuming that epidemiological link between leishmaniasis and TOSV infection may be represented by the exposure to the bite of a common vector, this study confirms the involvement of Phlebotomus perniciosus as the major vector of TOSV in the South of France. This study also suggests that some of the epidemiological data available on Leishmaniasis may be used to decipher the epidemiology of TOSV infections..The second part of this thesis was dedicated to detection, isolation and characterization of existing and/or new phleboviruses in sandfly populations in France and in North Africa. To achieve this aim, we had to set up a high-throughput cost-effective platform amenable to virus discovery in sandflies; this sandfly-processing platform has been recently docked to a Next Generation Sequencing platform for full genetic characterization of newly isolated and discovered viruses. A total of 12,576 sandflies were trapped during 12 campaigns conducted in France, Tunisia and Algeria. The discovery of several new phleboviruses and their observed frequency in sandfly populations has clearly demonstrated that within a given geographic area, virus diversity is much higher than previously believed.In the third part of this thesis, a seroprevalence study based on comparative virus neutralization tests was performed on human sera and allowed to exclude the newly described Punique virus from the list of major public health threats in northern Tunisia, and to confirm that TOSV is the dominant phleboviral pathogen with an impact on public health in this part of the country. This neutralization method is suitable to identify precisely the virus against which antibodues were elicited, allowing to discriminate among closely related phleboviruses, and to determine their propensity to play a role in public health.

Made available in DSpace on 2015-03-26T13:47:01Z (GMT). No. of bitstreams: 1 texto completo.pdf: 258964 bytes, checksum: 135e6be4766beec15d819dd30575f517 (MD5) Previous issue date: 2006-07-28 / Bovine herpesvirus type 5 (BoHV-5) is the etiological agent of the bovine meningoencephalitis that presents high morbidity in young bovine. Due to the similarity in the morphology of the virion, cytopathic effect in cell culture and antigenic properties, the BoHV-5 was classified erroneously as BoHV-1 in the past. BoHV-1 is responsible for respiratory and genital diseases, however the disease caused by BoHV-5 presents neurological clinical signs. This virus has been considered a variant of the same agent (BoHV-1) with neuropathogenic characteristics. Comparative studies among isolates of BoHV-5 revealed 97% of proteic similarity. However, the amino-terminal region of the most abundant glycoprotein of the viral envelope, the gC, differs substantially. This glycoprotein is involved in the initial interactions of the virus with the cellular surface besides of presenting as target for antibodies with neutralizing activities. This study aimed at to select an isolate of BoHV-5, among 5 isolates collected in outbreaks in different properties in Brazil, presenting higher antigenicity in vaccinated animals. Vaccines were formulated using isolates ISO9898292, SV507, SV163, 1807 and EVI145 and administered to 5 groups of 10 sheeps, which have received two intramuscular doses on days 0 and 21. Collections of blood were accomplished for analysis of production of antibodies by virus-neutralization and attendance of possible clinical signs to the 63rd day after the first vaccination. Antibodies titers averages ranged from 6,85 and 14,92 on the day 0 before the first vaccination. Antibody peak were on day 14, ranged from 4,50 (isolated ISO9898292) to 138,63 (isolated SV163). A second peak was observed 14 days after the booster ranged from 7,77 (ISO9898292) to 1017,54 (1807). In the 42nd day after the booster, it was observed titers variation from 3,84 (ISO9898292) to 305,97 (1807). The discrepancy among titers of antibody of each group of animals suggests a smaller antigenicity of isolated ISO9898292 in relation to the others, demonstrating a possible variation among the isolates, what results in antigenic differences. All isolates, with exception to ISO9898292, were effective in the induction of antibodies. / O herpesvírus bovino tipo 5 (BoHV-5) é o agente etiológico da menigoencefalite bovina que apresenta alta morbidade em bovinos jovens. Devido à similaridade na morfologia do virion, efeito citopático na cultura de células e propriedades antigênicas, o BoHV-5 foi classificado erroneamente como herpesvírus bovino tipo 1 (BoHV-1). Este vírus é responsável por doenças respiratórias e genitais, porém a doença causada pelo BoHV-5 apresenta sinais clínicos neurológicos, com isso o vírus foi considerado uma variante do mesmo agente com características de neuropatogenicidade. Estudos comparativos entre isolados de BoHV-5 revelaram 97% de similaridade protéica. No entanto, a região amino terminal da glicoproteína mais abundante do envelope viral, a gC, difere substancialmente. Esta glicoproteína está envolvida nas interações iniciais do vírus com a superfície celular, além de se apresentar como alvo para anticorpos com atividades neutralizantes. Este estudo objetivou selecionar um isolado do vírus BoHV-5, entre 5 isolados coletados em surtos da doença em diferentes propriedades, que confira maior antigenicidade em animais vacinados. As vacinas foram formuladas com os isolados ISO9898292, SV507, SV163, 1807 e EVI145 e administradas a 5 grupos de 10 ovelhas, as quais receberam duas doses vacinais por via intramuscular nos dias 0 e 21. Foram realizadas coletas de sangue para análise de produção de anticorpos por virusneutralização e acompanhamento de possíveis sinais clínicos até o 63º dia após a primo-vacinação. Foram observados dois picos na curva de anticorpos, o primeiro no dia 14, após a vacinação, onde os títulos de anticorpos variaram entre 4,50 (isolado ISO9898292) a 138,62 (isolado SV163). O segundo pico foi observado 14 dias após a revacinação onde os títulos variaram entre 7,77 (ISO9898292) a 1017,54 (1807). No 42º dia após a revacinação observou-se variação de título entre 3,84 (ISO9898292) a 305,97 (1807). A discrepância entre as médias de título de anticorpo de cada grupo de animais sugere uma menor antigenicidade do isolado ISO9898292 em relação aos demais, demonstrando uma possível variação entre os isolados, o que resulta em diferenças antigênicas. Todos os isolados, com exceção ao ISO9898292, mostraram-se eficazes na indução de anticorpos.

Le virus Epstein-Barr (VEB) est fortement associé au développement de syndromes lymphoprolifératifs (SLP) en greffe pédiatrique. Ce virus a la capacité d’immortaliser les lymphocytes B et de provoquer leur prolifération incontrôlée chez l’hôte immunodéprimé. Plusieurs études démontrent que le cycle lytique du virus jouerait un rôle primordial dans la genèse des SLP en produisant des particules virales pouvant infecter les cellules B adjacentes. Chez un individu immunodéprimé, ces cellules B nouvellement infectées peuvent donner naissance à une expansion lymphocytaire. Le projet présenté dans ce mémoire fait partie d’un programme de recherche visant à élucider le rôle de l’infection productive par le VEB dans le développement des SLP. L’objectif précis de ce projet est de développer un anticorps monoclonal chimère contre la glycoprotéine gp350 du VEB dans le but de neutraliser le virus et d’ainsi prévenir son entrée dans les cellules B. Notre laboratoire a construit une version chimère de l’anticorps monoclonal murin 72A1, lequel se lie à la gp350 et bloque l’infection. Les premiers essais ont révélé la présence de chaînes non fonctionnelles (aberrantes) dans l’hybridome produisant l’anticorps 72A1. La construction de la chaîne légère authentique est maintenant complète alors que celle de la chaîne lourde est toujours en cours. Le processus de caractérisation de l’anticorps chimère inclura des essais de cytotoxicité à médiation cellulaire dépendante des anticorps (ADCC). Dans cette optique, une lignée cellulaire exprimant de façon stable la gp350 a été établie. Notre anticorps chimère anti-gp350 pourrait éventuellement être utilisé comme thérapie préventive chez les greffés présentant un risque élevé de SLP en empêchant l’infection des cellules B adjacentes. / The Epstein-Barr virus (EBV) is associated with B-cell post-transplant lymphoproliferative disease (PTLD). EBV has the unique property of immortalizing B lymphocytes, thereby causing their uncontrolled proliferation in an immunocompromised host. Certain evidence suggests that EBV productive infection may play a primary role in the genesis of PTLD by generating virus particles which can infect bystander B cells. In an immunocompromised individual, these infected B cells may then give rise to expanding B-cell clones. The project presented in this thesis is part of a research program seeking to elucidate the role of EBV productive infection in the genesis of PTLD. The specific aim of this work was to design a chimeric monoclonal antibody against the EBV envelope glycoprotein gp350 in order to neutralize the virus, thereby preventing entry into B cells. Our laboratory constructed a chimeric version of the murine monoclonal antibody, 72A1, which binds to gp350 and blocks infection. The initial cloning attempts revealed the presence of nonfunctional (aberrant) transcripts in the hybridoma line producing the 72A1 antibody. The chimeric version of the authentic light chain is now completed while the chimeric heavy chain construction is ongoing. As part of the characterisation process for the chimeric antibody, a cell line stably expressing surface gp350 was generated. This gp350-expressing cell line will be used for antibody dependent cellular cytotoxicity assays (ADCC). This anti-gp350 chimeric antibody could be useful as a preventive therapy in transplant patients at high risk for PTLD by blocking the infection of bystander B cells.