RESUMEN
A vampire bat, Desmodus rotundus, captured in Oaxaca, Mexico, in August 1970, was found to be infected with the epidemic strain of Venezuelan equine encephalomyelitis virus at the same time that an equine epizootic was occurring there.
Asunto(s)
Quirópteros , Virus de la Encefalitis/aislamiento & purificación , Animales , Antígenos Virales/análisis , Virus de la Encefalitis Equina Venezolana/inmunología , Virus de la Encefalitis Equina Venezolana/aislamiento & purificación , Pruebas de Inhibición de Hemaglutinación , MéxicoRESUMEN
A virus morphologically resembling members of the family Paramyxoviridae has been isolated from the brain of a piglet with a central nervous disorder accompanied by pneumonia and corneal opacity. The virus, designated LPM, grows in a large variety of cultured cell types and elicits a cytopathic effect including formation of syncytia and cytoplasmic inclusion bodies. The virus has hemagglutinating, neuraminidase and hemolytic activities. Studies on experimental transmission showed that young pigs are susceptible to infection which induced a disease similar to that in natural cases. The virus killed mice and chicken embryos. The structural proteins of LPM virus, as resolved by polyacrylamide gel electrophoresis are similar to those described for other paramyxoviruses. Serologically the virus proved to be distinct from the paramyxoviruses tested so far.
Asunto(s)
Encéfalo/microbiología , Encefalitis/veterinaria , Paramyxoviridae/aislamiento & purificación , Infecciones por Respirovirus/veterinaria , Enfermedades de los Porcinos/microbiología , Animales , Anticuerpos Antivirales/análisis , Opacidad de la Córnea/veterinaria , Efecto Citopatogénico Viral , Encefalitis/inmunología , Encefalitis/microbiología , Hemabsorción , Hemaglutinación por Virus , Hemólisis , México , Ratones , Neuraminidasa/metabolismo , Paramyxoviridae/análisis , Paramyxoviridae/inmunología , Paramyxoviridae/fisiología , Neumonía Viral/veterinaria , Infecciones por Respirovirus/inmunología , Infecciones por Respirovirus/microbiología , Porcinos , Enfermedades de los Porcinos/inmunología , Proteínas Virales/análisisRESUMEN
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.