First record of antibodies to the bluetongue virus in ewe (Ovis aries) in the state of Amazonas, Brazil / Primeiro registro de anticorpos para o vírus da língua azul em ovino (Ovis aries) no estado do Amazonas, Brasil

The objective of this work was to describe the first record of antibodies to the Bluetongue Virus (BTV) in ewe, in the state of Amazonas. The ewe, which was in twin pregnancy, gave birth on May 9, 2015, but a lamb died hours after delivery. Veterinary service was then requested by the owner, where emaciation, loss of wool, pyrexia, apathy, dyspnea, mucoid nasal secretion, facial, lingual and submandibular edema were observed. There was a visit by the Agricultural Defense Agency of the State of Amazonas to the property and blood samples were collected from the animal. The whole blood and serum were sent to the National Agricultural Laboratory, where it was possible to detect the presence of specific antibodies to BTV, through the Agar Gel Double Immunodiffusion. The ewe was submitted to a new blood collection, following the same protocols and the samples were sent to the Biological Institute of São Paulo, confirmed diagnosis. The animal in a serious clinical condition, could not resist and died in July 2015. The occurrence of an allochthonous case, in an area where vector insects occur, can trigger an endemic process in the Amazon region. With this, the epidemiological control of these occurrences is necessary, in order to avoid the spread of the disease in the country.

O objetivo do trabalho foi descrever o primeiro registro de anticorpos para o Vírus da Língua Azul (VLA) em ovino, no estado do Amazonas. A ovelha, que se encontrava em gestação gemelar, pariu no dia 9 de maio de 2015, porém um cordeiro faleceu horas após o parto. Foi então solicitado serviço veterinário por parte do proprietário, onde foi observado emaciação, perda de lã, pirexia, apatia, dispneia, secreção nasal mucoide, edema facial, lingual e submandibular. Houve visita da Agência de Defesa Agropecuária do Estado do Amazonas na propriedade e coletadas amostras de sangue do animal. O sangue total e soro foram enviados ao Laboratório Nacional Agropecuário, no qual foi possível detectar a presença de anticorpos específicos para VLA, através do teste de Imunodifusão Dupla em Gel de Ágar. A ovelha foi submetida a uma nova coleta de sangue, seguindo os mesmos protocolos e as amostras foram enviadas ao Instituto Biológico de São Paulo, confirmando diagnóstico. O animal em estado clínico grave, não resistiu e veio a óbito em julho de 2015. A ocorrência de um caso alóctone, em uma área de ocorrência de insetos vetores, pode desencadear um processo de endemia na região amazônica. Com isso, o controle epidemiológico destas ocorrências, se fazem necessários, afim de se evitar a disseminação da doença no país.

Lengua Azul: Aislamiento y caracterización del virus e identificación de vectores en el noreste argentino / Bluetongue: isolation and characterization of the virus and identification of vectors in northeastern Argentina

To establish if BTV was circulating in Argentina, 94 bovines from the Santo TomÚ and Ituzaingó Departments of Corrientes Province were sampled every 30-60 days during 14 months. Red blood cells from those animals that showed seroconvertion with a c-ELISA were processed for virus isolation by inoculation in embryonated chicken eggs and cell cultures. Cells with CPE were positive by direct and indirect immunofluorescence with BTV specific reagents. These samples examined by electron microscopy showed virus particles with BTV morphological characteristics. Blood samples and tissue culture supernantants were positive by RT-PCR technique with primers corresponding to the segment 3 of the BTV genome. Haematophagous insects were captured in one farm using light traps and Culicoides insignis Lutz was the predominant species detected. This is the first isolation of BTV in Argentina from northeastern bovines without any disease symptom.

Relative superiority of c-ELISA for detection of bluetongue virus antibodies.

Anti-VP7 bluetongue virus (BTV) antibodies were detected in sera of ruminant livestock using competitive enzyme linked immunosorbent assay (c-ELISA). The per cent positivity for BTV antibodies recorded in sheep was 34.61% in Haryana, 7.14% in Himachal Pradesh and 28.88% in Punjab. Goat showed 64% positivity in Haryana, 67.34% in Himachal Pradesh and 88.33% in Rajasthan whereas cattle showed 67.44% positivity in Haryana, 52.17% in Punjab and 59.15% in Rajasthan for BTV antibodies. The percent positivity recorded for buffalo was 54.05% in Punjab. A comparison of c-ELISA with dot-ELISA for a total of 181 serum samples of sheep and cattle was also done. The performance of c-ELISA relative to dot-ELISA was found to have a sensitivity of 84.61% and specificity of 89.32%.

Investigación serologica de la lengua azúl en el Estado de Tamaulipas / Serological survery of bluetongue in the State of Tamaulipas, México

Se describen las características de una enfermedad viral designada como lengua azul" en ovinos, bovinos y caprinos y su prevalencia en el Estado de Texas. La vecindad con ese Estado y su fácil propagación por vectores hace posible la presencia de esa enzootia en los Estados fronterizos de México. Los datos hasta ahora conocidos son aislados y ésto hace necesario un estudio sistemático. Sin embargo, ante la inconveniencia de trabajar con un virus infectivo como antígeno, ya que habría el riesgo de introducirlo en el país, se empleó la técnica serológica de microinmunodifusión en agar gelificado con antígeno no infectivo. Se describe la técnica empleada y se consignan los resultados obtenidos en 1186 sueros con la seguiente distribución: 180 muestras de bovinos, 106 de caprinos y 896 de ovinos, todas estas muestras provinieron de 10 ranchos de Tamaulipas. En las muestras de bovinos 39 (21.66%) resultaron positivas; en caprinos 22 también reaccionaron positivamente (20.75%) y en ovinos 234 (26.11%) también fueron positivos. Estos datos hacen inegable la presencia de la "lengua azul" en el Estado de Tamaulipas con una alta prevalencia