ARS | Publication request: The affect of infectious bursal disease virus on avian influenza virus vaccine efficacy

Submitted to: American Association of Avian Pathologist
Publication Type: Abstract Only
Publication Acceptance Date: December 21, 2012
Publication Date: N/A

Technical Abstract: Immunosuppressive viruses are known to affect vaccinal immunity, however the impact of virally induced immunosuppression on avian influenza vaccine efficacy has not been quantified. In order to determine the effect of exposure to infectious bursal disease virus (IBDV) on vaccinal immunity to highly pathogenic avian influenza virus (AIV), vaccination-challenge studies that incorporated an evaluation of mean infectious dose were conducted. Specific pathogen free white rock chickens were exposed to variant E IBDV at one week of age, then were inoculated with an inactivated, oil adjuvanted H7 AIV vaccine. Three weeks post vaccination the chickens were challenged with four different doses of the same highly pathogenic AIV used to prepare the vaccine. Mortality in chickens exposed to IBDV was similar to mortality in challenge controls, regardless of vaccination status. Chickens which were vaccinated but not exposed to IBDV were protected from mortality and morbidity. Virus shed and antibody response to the vaccine are being evaluated as well.