Use of Heterologous Live IBV Vaccines in Day-old Commercial Broiler Chick Enhances The Protection against Middle East Variant Infectious Bronchitis Viruses

Faez Awad, Rajesh Chhabra, Anne Forrester, Matthew Baylis, Stephane Lemiere, Ilaria Capua, Hussein Aly Hussein & Kannan Ganapathy



  • IBV IS/885/00 and IS/1494/06, or those with high similarities to these strains, have been reported throughout the Middle East and North.
  • In most cases, severe respiratory distress and renal lesions with high mortality were observed in flocks affected by these strains.
  • It appears that conventional vaccines alone do not provide sufficient protection against these strains.
  • Use of different combinations of live IBV vaccines has been shown to induce high and broad protection against challenges with several heterologous virulent IBV variants.

The objective of this study was to evaluate the protection conferred by available live IBV vaccines when used in strategic manner against the two prominent Middle East variant IBVs that are related to IS/885/00 and IS/1494/06 (Variant 2).