Development of attenuated vaccines from Taiwanese infectious bronchitis virus strains

Development of attenuated vaccines from Taiwanese infectious bronchitis virus strains.

Due to variations in serotypes among different strains of avian infectious bronchitis viruses (IBV), vaccination of chicks with imported vaccines fails to protect them from IBV infections in Taiwan. Therefore, we develop attenuated vaccines from local strains in Taiwan. A Taiwan Group I (TW I) strain was passaged 74 times through specific pathogen-free (SPF) chicken embryonated eggs, and then t...

Isolation and Identification of Infectious Bronchitis Virus from Commercial Chickens

Live attenuated nephropathogenic infectious bronchitis virus vaccine provides broad cross protection against new variant strains.

Infectious bronchitis virus (IBV) infections cause great economic losses to the poultry industry worldwide, and the emergence of new variant strains complicates disease control. The present study investigated the genetic and protectotypic features of newly emerged Korean IBV strains. A phylogenetic analysis showed that several recent isolates formed 2 different clusters (new cluster 1 and 2), w...

pH stability studies with avian infectious bronchitis virus (coronavirus) strains.

A comparison of 17 infectious bronchitis virus strains, using the same test procedure and assay system, demonstrated that stability at an acid pH is a variable characteristic of the avian coronaviruses.

Avian infectious bronchitis virus.

Infectious bronchitis virus (IBV) is prevalent in all countries with an intensive poultry industry, with the incidence of infection approaching 100% in most locations. Vaccination is only partially successful due to the continual emergence of antigenic variants. At many sites, multiple antigenic types are simultaneously present, requiring the application of multiple vaccines. Although many coun...