RESUMO
Oryzoborus angolensis (Lesser Seed-Finch), Oryzoborus crassirostris (Large-billed Seed-Finch), and Sporophila intermedia (Grey Seedeater) are finch species native to the Caribbean island of Trinidad. These species are locally trapped and kept for their song, but with declining native populations, enthusiasts have turned to illegally importing birds from the South American mainland. The smuggling of wild birds from South America poses significant disease risks to the native bird species of Trinidad. Herein we describe the first case of poxviral infection in these illegally imported birds in Trinidad and partial genome sequence of the causative agent. Phylogenetic analysis of the 4b core protein sequence indicated that the avian poxvirus identified was most closely related to a 2012 avian pox sequence from Brazil, with 96.2% and 98.1% identity at the nucleotide and amino acid level.
Assuntos
Doenças das Aves/virologia , Genoma Viral , Infecções por Poxviridae/veterinária , Poxviridae/genética , Poxviridae/isolamento & purificação , Aves Canoras , Distribuição Animal , Animais , Comércio , Tentilhões , Filogenia , Poxviridae/classificação , Infecções por Poxviridae/virologia , Análise de Sequência de DNA/veterinária , Trinidad e TobagoRESUMO
The poxviruses identified in cetaceans are associated with characteristic tattoo or ring skin lesions. However, little is known regarding the prevalence and progression of these lesions and the molecular characterization of cetacean poxviruses in the Southern Hemisphere. This manuscript describes the progression of poxvirus-like skin lesions in 5 free-ranging Guiana dolphins Sotalia guianensis. Additionally, 151 skin samples from 113 free-ranging cetaceans from Brazil, including 4 animals with tattoo skin lesions, were selected for poxvirus testing. Poxviral DNA polymerase gene PCR amplification was used to detect the virus in ß-actin-positive samples (145/151). DNA topoisomerase I gene PCR was then used in Cetaceanpoxvirus (CePV)-positive cases (n = 2), which were further evaluated by histopathology and electron microscopy. Based on photo-identification, adult Guiana dolphins presented regressing or healed poxvirus-like lesions (2/2), while juveniles presented persistent (2/3) or healed and progressive lesions (1/3). CePV DNA was amplified in a common bottlenose dolphin Tursiops truncatus and in a Guiana dolphin. Intracytoplasmic inclusion bodies and viral particles consistent with poxvirus were identified by histology and electron microscopy, respectively. CePV-specific amino acid motifs were identified through phylogenetic analysis. Our findings corroborate previous studies that suggest the placement of poxviruses from cetaceans within the novel CePV genus. This is the first molecular identification of poxvirus in South American odontocetes.
Assuntos
Golfinho Nariz-de-Garrafa , Filogenia , Infecções por Poxviridae , Poxviridae , Animais , Golfinho Nariz-de-Garrafa/virologia , Brasil , Poxviridae/isolamento & purificação , Infecções por Poxviridae/veterináriaRESUMO
Bovine vaccinia (BV) is a vesicular disease induced by the Vaccinia virus (VACV) that affects milk production and is an occupational zoonosis. This research had the following objectives: (i) detection of VACV by qPCR in cattle with clinical suspicion of vesicular disease; (ii) symptoms characterization in animals and milkers with clinical suspicion of the disease and virus detection in humans; and (iii) identification of risk factors for infections of VACV in herds from several Brazilian states. A total of 471 bovine epithelial samples from dairy farms, in 15 Brazilian states, were evaluated between 2007 and 2012. The samples were tested by quantitative PCR (qPCR) using SYBR Green® reagents, validated with a lower limit of detection of 10 TCID50/50µL (1.7x10 viral particles), and 45.1% of VACV positive samples were detected. Using official forms for epidemiological investigation (FORM-IN), the risk factors for VACV infections in cattle were determined to be farms with a lack of technological facilities (P=0.029) and the presence of rodents (P=0.001). There was an effect of seasonality in cattle with a higher occurrence of BV during the dry season. A total of 420 epidemiological questionnaires were applied at public health care centers, where 100% of the milkers had vesicular lesions on their hands (98.1%) and on their arms (6.9%). The most frequent clinical symptoms in humans were: local swelling (74.2%), headache (20.7%), fever (10.4%) and inguinal lymphadenopathy (74.2%). Only 19.98% of milkers aged between 39 and 58 years were seroreactive to VACV and were immunized with the human anti-smallpox vaccine. There was an increase in the frequency of BV in older individuals due to their natural decrease in specific immunity. It has been shown that the implementation of zootechnical management techniques and health planning are important for the prevention of BV in animals and humans.(AU)
Vaccinia bovina (VB) é uma doença vesicular induzida pelo Vaccinia virus (VACV) que afeta a produção de leite e é uma zoonose ocupacional. Este trabalho teve os seguintes objetivos: (i) detecção de VACV por qPCR em bovinos com suspeita clínica de doença vesicular; (ii) caracterização dos sintomas apresentados por animais e ordenhadores com suspeita clínica da doença e detecção do vírus em humanos; e (iii) identificação de fatores de risco para infecção por VACV em rebanhos de vários estados brasileiros. Um total de 471 amostras de epitélio bovino de fazendas leiteiras, em 15 estados brasileiros, foram avaliados entre 2007 e 2012. As amostras foram testadas por PCR quantitativa (qPCR) usando reagentes SYBR Green®, validados com um limite inferior de detecção de 10TCID50/50L (1,7x10 partículas virais) e 45,1% das amostras positivas de VACV foram detectadas. Usando formulários oficiais de investigação epidemiológica (FORM-IN), os fatores de risco para infecções por VACV em bovinos foram determinados como fazendas com falta de instalações tecnológicas (P=0,029) e presença de roedores (P=0,001). Houve um efeito da sazonalidade no gado com maior ocorrência de VB durante a estação seca. Um total de 420 questionários epidemiológicos foram aplicados nos centros públicos de saúde, onde 100% dos ordenhadores apresentaram lesões vesiculares nas mãos (98,1%) e nos braços (6,9%). Os sintomas clínicos mais frequentes em humanos foram: inchaço local (74,2%), cefaleia (20,7%), febre (10,4%) e linfadenopatia inguinal (74,2%). Apenas 19,98% dos produtores de leite com idade entre 39 e 58 anos foram sororreagentes ao VACV e foram imunizados com a vacina contra a varíola humana. Houve um aumento na frequência de BV em indivíduos mais velhos devido à sua diminuição natural na imunidade específica. Demonstrou-se que a implementação de técnicas de gestão zootécnica e planejamento sanitário são importantes para a prevenção da VB em animais e seres humanos.(AU)
Assuntos
Animais , Bovinos , Vacínia/veterinária , Vaccinia virus , Poxviridae/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Doenças ProfissionaisRESUMO
Bovine vaccinia (BV) is a vesicular disease induced by the Vaccinia virus (VACV) that affects milk production and is an occupational zoonosis. This research had the following objectives: (i) detection of VACV by qPCR in cattle with clinical suspicion of vesicular disease; (ii) symptoms characterization in animals and milkers with clinical suspicion of the disease and virus detection in humans; and (iii) identification of risk factors for infections of VACV in herds from several Brazilian states. A total of 471 bovine epithelial samples from dairy farms, in 15 Brazilian states, were evaluated between 2007 and 2012. The samples were tested by quantitative PCR (qPCR) using SYBR Green® reagents, validated with a lower limit of detection of 10 TCID50/50µL (1.7x10 viral particles), and 45.1% of VACV positive samples were detected. Using official forms for epidemiological investigation (FORM-IN), the risk factors for VACV infections in cattle were determined to be farms with a lack of technological facilities (P=0.029) and the presence of rodents (P=0.001). There was an effect of seasonality in cattle with a higher occurrence of BV during the dry season. A total of 420 epidemiological questionnaires were applied at public health care centers, where 100% of the milkers had vesicular lesions on their hands (98.1%) and on their arms (6.9%). The most frequent clinical symptoms in humans were: local swelling (74.2%), headache (20.7%), fever (10.4%) and inguinal lymphadenopathy (74.2%). Only 19.98% of milkers aged between 39 and 58 years were seroreactive to VACV and were immunized with the human anti-smallpox vaccine. There was an increase in the frequency of BV in older individuals due to their natural decrease in specific immunity. It has been shown that the implementation of zootechnical management techniques and health planning are important for the prevention of BV in animals and humans.
Vaccinia bovina (VB) é uma doença vesicular induzida pelo Vaccinia virus (VACV) que afeta a produção de leite e é uma zoonose ocupacional. Este trabalho teve os seguintes objetivos: (i) detecção de VACV por qPCR em bovinos com suspeita clínica de doença vesicular; (ii) caracterização dos sintomas apresentados por animais e ordenhadores com suspeita clínica da doença e detecção do vírus em humanos; e (iii) identificação de fatores de risco para infecção por VACV em rebanhos de vários estados brasileiros. Um total de 471 amostras de epitélio bovino de fazendas leiteiras, em 15 estados brasileiros, foram avaliados entre 2007 e 2012. As amostras foram testadas por PCR quantitativa (qPCR) usando reagentes SYBR Green®, validados com um limite inferior de detecção de 10TCID50/50L (1,7x10 partículas virais) e 45,1% das amostras positivas de VACV foram detectadas. Usando formulários oficiais de investigação epidemiológica (FORM-IN), os fatores de risco para infecções por VACV em bovinos foram determinados como fazendas com falta de instalações tecnológicas (P=0,029) e presença de roedores (P=0,001). Houve um efeito da sazonalidade no gado com maior ocorrência de VB durante a estação seca. Um total de 420 questionários epidemiológicos foram aplicados nos centros públicos de saúde, onde 100% dos ordenhadores apresentaram lesões vesiculares nas mãos (98,1%) e nos braços (6,9%). Os sintomas clínicos mais frequentes em humanos foram: inchaço local (74,2%), cefaleia (20,7%), febre (10,4%) e linfadenopatia inguinal (74,2%). Apenas 19,98% dos produtores de leite com idade entre 39 e 58 anos foram sororreagentes ao VACV e foram imunizados com a vacina contra a varíola humana. Houve um aumento na frequência de BV em indivíduos mais velhos devido à sua diminuição natural na imunidade específica. Demonstrou-se que a implementação de técnicas de gestão zootécnica e planejamento sanitário são importantes para a prevenção da VB em animais e seres humanos.
Assuntos
Animais , Bovinos , Poxviridae/isolamento & purificação , Vacínia/veterinária , Vaccinia virus , Doenças Profissionais , Reação em Cadeia da Polimerase/veterináriaRESUMO
Bats (Order Chiroptera) are an abundant group of mammals with tremendous ecological value as insectivores and plant dispersers, but their role as reservoirs of zoonotic diseases has received more attention in the last decade. With the goal of managing disease in free-ranging bats, we tested modified vaccinia Ankara (MVA) and raccoon poxvirus (RCN) as potential vaccine vectors in the Brazilian Free-tailed bat (Tadarida brasiliensis), using biophotonic in vivo imaging and immunogenicity studies. Animals were administered recombinant poxviral vectors expressing the luciferase gene (MVA-luc, RCN-luc) through oronasal (ON) or intramuscular (IM) routes and subsequently monitored for bioluminescent signal indicative of viral infection. No clinical illness was noted after exposure to any of the vectors, and limited luciferase expression was observed. Higher and longer levels of expression were observed with the RCN-luc construct. When given IM, luciferase expression was limited to the site of injection, while ON exposure led to initial expression in the oral cavity, often followed by secondary replication at another location, likely the gastric mucosa or gastric associated lymphatic tissue. Viral DNA was detected in oral swabs up to 7 and 9 days post infection (dpi) for MVA and RCN, respectively. While no live virus was detected in oral swabs from MVA-infected bats, titers up to 3.88 x 104 PFU/ml were recovered from oral swabs of RCN-infected bats. Viral DNA was also detected in fecal samples from two bats inoculated IM with RCN, but no live virus was recovered. Finally, we examined the immunogenicity of a RCN based rabies vaccine (RCN-G) following ON administration. Significant rabies neutralizing antibody titers were detected in the serum of immunized bats using the rapid fluorescence focus inhibition test (RFFIT). These studies highlight the safety and immunogenicity of attenuated poxviruses and their potential use as vaccine vectors in bats.
Assuntos
Anticorpos Antivirais/sangue , Quirópteros/imunologia , Imunogenicidade da Vacina , Poxviridae/imunologia , Vacina Antirrábica/imunologia , Vírus da Raiva/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Quirópteros/virologia , Vetores Genéticos , Luciferases/genética , Medições Luminescentes , Masculino , Boca/virologia , Orthopoxvirus/genética , Orthopoxvirus/fisiologia , Poxviridae/isolamento & purificação , Poxviridae/fisiologia , Raiva/prevenção & controle , Raiva/veterinária , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/genética , Vacinação/métodos , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/imunologia , Vaccinia virus/genética , Vaccinia virus/imunologia , Vaccinia virus/isolamento & purificação , Vaccinia virus/fisiologia , Replicação ViralRESUMO
This study represents the first phylogenetic analysis of avian poxvirus recovered from turkeys in Brazil. The clinical disorders related to fowlpox herein described occurred in a turkey housing system. The birds displaying characteristic pox lesions which were observed on the neck, eyelids and beak of the turkeys. Four affected turkeys were randomly chosen, euthanized and necropsied. Tissues samples were submitted for histopathological analysis and total DNA was further extracted, amplified by conventional PCR, sequenced and phylogenetically analyzed. Avian poxviruses specific PCR was performed based on P4b core protein gene sequence. The histological analysis revealed dermal inflammatory process, granulation tissue, hyperplasia of epithelial cells and inclusion bodies. The P4b gene was detected in all samples. Sequencing revealed a 100% nucleotide and amino acid sequence identity among the samples, and the sequences were deposited in GenBank®. The four Avian poxviruses fragments sequenced in this study clustered along the A1 clade of avipoxviruses, and were classified as Avipoxvirus (APV). Additional studies, such as virus isolation, PCR and sequencing includinga large number of specimens from the Brazilian turkey production must be conducted due to the hazardous risk that poxvirus infections may cause to the Brazilian poultry production scenario, given that Brazil's turkey production attracts attention due to its economic importance worldwide. Our findings point to the need to identify the prevalence of APV in Brazilian turkey production, to perform risk assessment studies and continued surveillance of APV infections in both wild and commercial avian species.
Este trabalho representa a primeira análise filogenética de Poxvirus aviário detectado em perus no Brasil. Os distúrbios clínicos relacionados com bouba aviária aqui descritos ocorreram em um sistema de alojamento de perus. As aves apresentaram lesões características de varíola observadas no pescoço, pálpebras e bico das aves. Quatro perus com sinais característicos foram escolhidos aleatoriamente, sacrificados e submetidos à autópsia. Amostras de tecido foram submetidas à análise histopatológica e o DNA total foi extraído, amplificado por PCR convencional e os amplicons foram sequenciados e analisados filogeneticamente. A PCR específica para Poxvírus aviário foi realizada com base na seqüência do gene da proteína do núcleo P4b. A análise histológica revelou um processo inflamatório dérmico, tecido de granulação, hiperplasia de células epiteliais e corpúsculos de inclusão. O gene P4b foi detectado em todas as amostras. O sequenciamento revelou uma identidade entre nucleotídeos e aminoácido de 100% entre as amostras e as sequências foram depositadas no GenBank®. Os quatro fragmentos de poxvírus aviário sequenciado neste estudo foram agrupados no clado A1 de avipoxvirus e foram classificados como Avipoxvirus (APV). Estudos adicionais, como isolamento viral, PCR e sequenciamento, incluindo um grande número de perus da produção brasileira devem ser conduzidos devido ao grave risco que a infecção por poxvírus pode causar ao cenário de produção avícola brasileira, tendo em vista que a produção brasileira de perus atrai atenção devido a sua importância mundial. Nossos resultados apontam para a necessidade de identificar a prevalência da APV na produção de peru no Brasil, para realizar estudos de avaliação de risco e continuada monitoração de infecções por APV nas espécies de aves comerciais e silvestres.
Assuntos
Animais , Avipoxvirus/isolamento & purificação , Filogenia , Perus/microbiologia , Poxviridae/isolamento & purificação , Reação em Cadeia da Polimerase/veterináriaRESUMO
This study represents the first phylogenetic analysis of avian poxvirus recovered from turkeys in Brazil. The clinical disorders related to fowlpox herein described occurred in a turkey housing system. The birds displaying characteristic pox lesions which were observed on the neck, eyelids and beak of the turkeys. Four affected turkeys were randomly chosen, euthanized and necropsied. Tissues samples were submitted for histopathological analysis and total DNA was further extracted, amplified by conventional PCR, sequenced and phylogenetically analyzed. Avian poxviruses specific PCR was performed based on P4b core protein gene sequence. The histological analysis revealed dermal inflammatory process, granulation tissue, hyperplasia of epithelial cells and inclusion bodies. The P4b gene was detected in all samples. Sequencing revealed a 100% nucleotide and amino acid sequence identity among the samples, and the sequences were deposited in GenBank®. The four Avian poxviruses fragments sequenced in this study clustered along the A1 clade of avipoxviruses, and were classified as Avipoxvirus (APV). Additional studies, such as virus isolation, PCR and sequencing includinga large number of specimens from the Brazilian turkey production must be conducted due to the hazardous risk that poxvirus infections may cause to the Brazilian poultry production scenario, given that Brazil's turkey production attracts attention due to its economic importance worldwide. Our findings point to the need to identify the prevalence of APV in Brazilian turkey production, to perform risk assessment studies and continued surveillance of APV infections in both wild and commercial avian species.(AU)
Este trabalho representa a primeira análise filogenética de Poxvirus aviário detectado em perus no Brasil. Os distúrbios clínicos relacionados com bouba aviária aqui descritos ocorreram em um sistema de alojamento de perus. As aves apresentaram lesões características de varíola observadas no pescoço, pálpebras e bico das aves. Quatro perus com sinais característicos foram escolhidos aleatoriamente, sacrificados e submetidos à autópsia. Amostras de tecido foram submetidas à análise histopatológica e o DNA total foi extraído, amplificado por PCR convencional e os amplicons foram sequenciados e analisados filogeneticamente. A PCR específica para Poxvírus aviário foi realizada com base na seqüência do gene da proteína do núcleo P4b. A análise histológica revelou um processo inflamatório dérmico, tecido de granulação, hiperplasia de células epiteliais e corpúsculos de inclusão. O gene P4b foi detectado em todas as amostras. O sequenciamento revelou uma identidade entre nucleotídeos e aminoácido de 100% entre as amostras e as sequências foram depositadas no GenBank®. Os quatro fragmentos de poxvírus aviário sequenciado neste estudo foram agrupados no clado A1 de avipoxvirus e foram classificados como Avipoxvirus (APV). Estudos adicionais, como isolamento viral, PCR e sequenciamento, incluindo um grande número de perus da produção brasileira devem ser conduzidos devido ao grave risco que a infecção por poxvírus pode causar ao cenário de produção avícola brasileira, tendo em vista que a produção brasileira de perus atrai atenção devido a sua importância mundial. Nossos resultados apontam para a necessidade de identificar a prevalência da APV na produção de peru no Brasil, para realizar estudos de avaliação de risco e continuada monitoração de infecções por APV nas espécies de aves comerciais e silvestres.(AU)
Assuntos
Animais , Perus/microbiologia , Filogenia , Poxviridae/isolamento & purificação , Avipoxvirus/isolamento & purificação , Reação em Cadeia da Polimerase/veterináriaRESUMO
Poxvirus skin disease has been reported in several species of cetaceans, principally in odontocetes, and a single report in mysticetes. Southern right whales Eubalaena australis in Peninsula Valdes, Argentina, show a variety of skin lesions of unknown etiology, and the number of these lesions has increased in recent years. Samples from dead whales were taken in order to establish the etiology of these lesions. One calf and one adult presented ring-type lesions, characterized by a circumscribed and slightly raised area of skin. Lesions were histologically characterized by the presence of microvesicles and vacuolated cells in the stratum spinosum, along with hyperplasia of the stratum corneum and eosinophilic inclusion bodies in the cytoplasm of the epithelial cells. Transmission electron microscopy showed aggregations of virions with typical poxvirus morphology. PCR of cetacean poxvirus (CPV) DNA polymerase, DNA topoisomerase I and parapoxvirus DNA polymerase gene fragments was done, and confirmed the presence of poxvirus in one sample. Phylogenetic analysis showed that the detected poxvirus belongs to the CPV-2 group. This is the first confirmed report of poxvirus in southern right whales in Argentina.
Assuntos
Filogenia , Infecções por Poxviridae/veterinária , Poxviridae/genética , Poxviridae/isolamento & purificação , Baleias , Animais , DNA Viral/genética , Microscopia Eletrônica de Transmissão , Infecções por Poxviridae/virologiaRESUMO
O ectima contagioso (também conhecido como orf), é uma doença debilitante de ovinos e caprinos causada pelo vírus do orf (ORFV). A vacinação tem sido usada com relativo sucesso no controle da doença. No entanto, as vacinas atuais contêm amostras virulentas do agente, são produzidas por escarificação cutânea de animais, e apresentam eficácia questionável. Assim, o presente trabalho teve como objetivo produzir e testar a eficácia de uma vacina experimental produzida em cultivo celular. A cepa IA-82 do ORFV foi submetida a 21 passagens em cultivo de células BHK-21 e usada para vacinar ovinos jovens (n=30), por escarificação cutânea na face interna da coxa. A vacinação produziu pústulas e crostas em 16 dos 30 ovinos vacinados, indicando imunização adequada. Noventa dias após a vacinação, ovinos vacinados (n=16) e controles (n=16) foram inoculados com uma cepa virulenta do ORFV (10(6,9)DICC50/mL) após escarificação na comissura labial. Todos os animais desenvolveram lesões típicas de ectima, incluindo hiperemia, vesículas, pústulas e crostas. No entanto, os animais vacinados desenvolveram lesões mais leves e passageiras do que os controles, e os escores clínicos foram estatisticamente diferentes (p<0,05) entre os dias 10 e 22 pós-desafio. Além disso, o tempo de duração da doença foi significativamente inferior (p<0,05) nos animais vacinados. Os animais vacinados também excretaram menor quantidade de vírus (p<0,05) e por um período significativamente mais curto do que os controles (13 dias versus 22 dias, p<0,001). Esses resultados demonstram a proteção parcial conferida pela vacina experimental e, dependendo da melhoria dos índices de imunização e proteção, são promissores no sentido da utilização de vacinas contra o ORFV produzidas em cultivo celular.(AU)
Contagious ecthyma, also known as orf, is a debilitating disease of sheep and goats caused by the parapoxvirus, orf virus (ORFV). Vaccination has been used with relative success to reduce the losses caused by the disease, yet the current vaccines contain virulent virus, are empirically produced through skin scarification of live lambs, and present questionable efficacy. Therefore, the present study aimed at developing and testing an experimental ORFV vaccine produced in tissue culture. The ORFV strain IA-82 was submitted to 21 passages in BHK-21 cells and then used to immunize lam bs (n=30) through skin scarification of the internal face of the hind limb. Vaccination produced localized pustules and scabs lesions in 16 out of 30 animals, indicating an adequate replication of the vaccine virus. Ninety days after vaccination, vaccinated (n=16) and control lambs (n=16) were inoculated with a virulent ORFV strain (10(6,9)TCID50/ml) in the labial commissure. Vaccinated and control lambs developed typical orf lesions, characterized by hyperemia, vesicles, pustules and scab formation. Nonetheless, vaccinated animals developed milder lesions compared to controls and the clinical scores were significantly lower (p<0.05) between days 10 and 22 post-challenge. In addition, the mean duration of clinical disease was significantly reduced in vaccinated animals (p<0.05). Furthermore, vaccinated animals excreted much less virus (p<0.05) and for a significantly shorter period of time than did the controls (13 days versus 22 days, p<0.001). These results demonstrate partial protection by the experimental vaccine and, upon improvement of immunization and protection indices, are promising towards the use of tissue culture-based ORFV vaccines.(AU)
Assuntos
Animais , Ovinos/imunologia , Ectima Contagioso/imunologia , Vacinas/biossíntese , Poxviridae/isolamento & purificação , Infecções por Poxviridae/transmissão , Técnicas de Cultura de Células , Técnicas de Cultura de Células/veterináriaRESUMO
O ectima contagioso (também conhecido como orf), é uma doença debilitante de ovinos e caprinos causada pelo vírus do orf (ORFV). A vacinação tem sido usada com relativo sucesso no controle da doença. No entanto, as vacinas atuais contêm amostras virulentas do agente, são produzidas por escarificação cutânea de animais, e apresentam eficácia questionável. Assim, o presente trabalho teve como objetivo produzir e testar a eficácia de uma vacina experimental produzida em cultivo celular. A cepa IA-82 do ORFV foi submetida a 21 passagens em cultivo de células BHK-21 e usada para vacinar ovinos jovens (n=30), por escarificação cutânea na face interna da coxa. A vacinação produziu pústulas e crostas em 16 dos 30 ovinos vacinados, indicando imunização adequada. Noventa dias após a vacinação, ovinos vacinados (n=16) e controles (n=16) foram inoculados com uma cepa virulenta do ORFV (10(6,9)DICC50/mL) após escarificação na comissura labial. Todos os animais desenvolveram lesões típicas de ectima, incluindo hiperemia, vesículas, pústulas e crostas. No entanto, os animais vacinados desenvolveram lesões mais leves e passageiras do que os controles, e os escores clínicos foram estatisticamente diferentes (p<0,05) entre os dias 10 e 22 pós-desafio. Além disso, o tempo de duração da doença foi significativamente inferior (p<0,05) nos animais vacinados. Os animais vacinados também excretaram menor quantidade de vírus (p<0,05) e por um período significativamente mais curto do que os controles (13 dias versus 22 dias, p<0,001). Esses resultados demonstram a proteção parcial conferida pela vacina experimental e, dependendo da melhoria dos índices de imunização e proteção, são promissores no sentido da utilização de vacinas contra o ORFV produzidas em cultivo celular.
Contagious ecthyma, also known as orf, is a debilitating disease of sheep and goats caused by the parapoxvirus, orf virus (ORFV). Vaccination has been used with relative success to reduce the losses caused by the disease, yet the current vaccines contain virulent virus, are empirically produced through skin scarification of live lambs, and present questionable efficacy. Therefore, the present study aimed at developing and testing an experimental ORFV vaccine produced in tissue culture. The ORFV strain IA-82 was submitted to 21 passages in BHK-21 cells and then used to immunize lam bs (n=30) through skin scarification of the internal face of the hind limb. Vaccination produced localized pustules and scabs lesions in 16 out of 30 animals, indicating an adequate replication of the vaccine virus. Ninety days after vaccination, vaccinated (n=16) and control lambs (n=16) were inoculated with a virulent ORFV strain (10(6,9)TCID50/ml) in the labial commissure. Vaccinated and control lambs developed typical orf lesions, characterized by hyperemia, vesicles, pustules and scab formation. Nonetheless, vaccinated animals developed milder lesions compared to controls and the clinical scores were significantly lower (p<0.05) between days 10 and 22 post-challenge. In addition, the mean duration of clinical disease was significantly reduced in vaccinated animals (p<0.05). Furthermore, vaccinated animals excreted much less virus (p<0.05) and for a significantly shorter period of time than did the controls (13 days versus 22 days, p<0.001). These results demonstrate partial protection by the experimental vaccine and, upon improvement of immunization and protection indices, are promising towards the use of tissue culture-based ORFV vaccines.
Assuntos
Animais , Ectima Contagioso/imunologia , Ovinos/imunologia , Poxviridae/isolamento & purificação , Vacinas/biossíntese , Infecções por Poxviridae/transmissão , Técnicas de Cultura de Células , Técnicas de Cultura de Células/veterináriaRESUMO
The biological properties of poxvirus isolates from skin lesions on dairy cows and milkers during recent exanthem episodes in Cantagalo County, Rio de Janeiro State, Brazil, were more like vaccinia virus (VV) than cowpox virus. PCR amplification of the hemagglutinin (HA) gene substantiated the isolate classification as an Old World orthopoxvirus, and alignment of the HA sequences with those of other orthopoxviruses indicated that all the isolates represented a single strain of VV, which we have designated Cantagalo virus (CTGV). HA sequences of the Brazilian smallpox vaccine strain (VV-IOC), used over 20 years ago, and CTGV showed 98.2% identity; phylogeny inference of CTGV, VV-IOC, and 12 VV strains placed VV-IOC and CTGV together in a distinct clade. Viral DNA restriction patterns and protein profiles showed a few differences between VV-IOC and CTGV. Together, the data suggested that CTGV may have derived from VV-IOC by persisting in an indigenous animal(s), accumulating polymorphisms, and now emerging in cattle and milkers as CTGV. CTGV may represent the first case of long-term persistence of vaccinia in the New World.
Assuntos
Doenças dos Bovinos/virologia , Surtos de Doenças/veterinária , Infecções por Poxviridae/veterinária , Poxviridae/classificação , Vacina Antivariólica , Sequência de Aminoácidos , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Chlorocebus aethiops , Exantema/epidemiologia , Exantema/virologia , Feminino , Hemaglutininas Virais/genética , Humanos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Poxviridae/genética , Poxviridae/isolamento & purificação , Infecções por Poxviridae/virologia , Alinhamento de Sequência , Vaccinia virus/genética , Vaccinia virus/imunologia , Células VeroRESUMO
In 1990, 74 dusky dolphins (Lagenorhynchus obscurus) and 10 Burmeister's porpoises (Phocoena spinipinnis) were examined for the presence of hyperpigmented marks and pinhole lesions on the skin (tattoo lesions) at the fishing terminal of Pucusana, central Peru. Prevalences of tattoo lesions were 8.1% and 30% in the dolphins and porpoises, respectively. Intracytoplasmic poxviruses were demonstrated by transmission electron microscopy in ultrathin sections of three of eight samples of infected epidermis from both species. The reason for the negative results in others is unclear but may be related to stages of infection with low virus density or even incorrect classification of some lesions as genuine viral tattoos. An irregular arrangement of tubules on the outer viral membrane, similar to those in orthopoxviruses, was visible in negative contrast preparations for P. spinipinnis. This is the first record of poxvirus in porpoises (Phocoenidae) and also the first report for dusky dolphins, and generally for cetaceans of the southern hemisphere.
Assuntos
Golfinhos , Infecções por Poxviridae/veterinária , Poxviridae/isolamento & purificação , Animais , Epiderme/microbiologia , Feminino , Masculino , Microscopia Eletrônica , Peru/epidemiologia , Poxviridae/ultraestrutura , Infecções por Poxviridae/epidemiologia , Prevalência , Pele/microbiologia , Pele/patologia , Vírion/isolamento & purificação , Vírion/ultraestruturaAssuntos
Surtos de Doenças/veterinária , Ectima Contagioso/microbiologia , Doenças das Cabras/microbiologia , Vírus do Orf/isolamento & purificação , Poxviridae/isolamento & purificação , Animais , Anticorpos Antivirais/análise , Brasil , Testes de Fixação de Complemento , Ectima Contagioso/epidemiologia , Doenças das Cabras/epidemiologia , Cabras , Microscopia Eletrônica , Vírus do Orf/imunologia , Vírus do Orf/ultraestruturaRESUMO
In a herd of 120 two to eight months old calves kept at a Mexican Government experimental station in Ajuchitlan, Querétaro, weight loss and ptialism were observed. Upon a clinical examination, it was found that 31 (25.8%) of the animals disclosed papules in the oral and perioral regions. Biopsies from the affected tissues were studied with the light and electron microscopes. Serological studies and isolation of the virus were also carried out. A Pox virus was identified (240 x 100 x 150 +/- 7% nm) with the electron microscope. Dermatophilus sp. was occasionally observed. Bovine kidney monolayers, inoculated with affected bovine tissues demonstrated cytopathic effect up to the 4th serial passage. Inoculation with cell cultured infectious material in the oral submucosa (cell lysate) produced typical lesions of BPS on a heifer. Infectious tissues from this experimentally inoculated animal produced cytopathic effect in tissue cultured cells after 24 hours, and this last material was infectious for a second young heifer. Virus-neutralization tests, using an hyperimmune serum, disclosed a neutralization index of 1.5 logarithms. It was concluded that bovine papular stomatitis virus was the etiological agent.