A vaccine programme comprising GA08 (GI-27) and Mass (GI-1) strains prevents DMV1639 (GI-17) infectious bronchitis virus transmission among broiler chickens.

Effective control of infectious bronchitis is a challenge in commercial poultry operations due to the high transmissibility of the virus. Although multiple IBV lineages are circulating in the United States, the DMV1639-type IBV strain (GI-17) is currently the major circulating variant, creating production losses in the poultry industry. This study aimed to test whether the combination of a GA08 (GI-27) and a Mass-type (GI-1) IB vaccines could significantly reduce the transmission of a DMV1639-type (GI-17) field IBV strain in 4-week-old commercial broilers.