Infectious Bronchitis Virus (IBV) in Chickens: A Comprehensive Overview

Infectious bronchitis virus (IBV) is a coronavirus that primarily affects chickens and causes significant economic losses to the poultry industry. It replicates in respiratory and gastrointestinal tissues, and can be found in both respiratory and fecal material. IBV can also infect other bird species, and the severity of infection varies among different chicken breeds, possibly due to differences in immune response. The existence of numerous serotypes of IBV makes vaccine development challenging, and the effectiveness of current vaccines is limited by poor cross-protection. The protective immune response to IBV is not well understood, but the surface spike protein, particularly the amino-terminal S1 half, is known to induce protective immunity. Minor differences in S proteins can affect cross-protection. Experimental vector IB vaccines and genetically manipulated IBVs show promise in developing more effective vaccines.