In vitro characterization and pathogenesis of Egypt/Beni- Suef/01; a novel genotype of infectious bronchitis virus

In vitro characterizations of infectious bronchitis virus (Egypt/Beni-Suef/01 strain) were studied. Heat stability at 56 °C for 5, 10, 15, 20, and 30 min, UV irradiation for 10, 15, 20, and 30 min, chloroform sensitivity, pH stability, and E/M examination were screened. Two-week-old commercial chickens were inoculatedintraocularly with Egypt/Beni-Suef/01. At days 1, 3, 5, 7, 11 and 14 days postinfection, three birds were euthanatized, and virus antigens were screened usingimmunofluorescence. Histopathology of both trachea & kidney was also performed.Egypt /Beni-Suef/01 was found to be sensitive to 56 °C for 5 min, UV for 10 minand chloroform but resistant to pH 3 and pH 9. It showed typical morphology ofcoronaviruses by E/M. The virus was found to induce mild respiratory signs andsever renal changes. Immunoflourescence staining showed viral antigen in larynx,trachea, thymus, lung, liver, spleen, renal tubules and glomeruli as well as bursa ofFabricius but not in pancreas. Marked histopathological lesions were also detectedin both trachea and kidneys.