Pathology

Phylogenetic tree

Virus

Avian infectious bronchitis

Avian infectious bronchitis virus

Disease

Infectious bronchitis virus

Coronavirus disease 2019 (COVID-19)

Infectious disease (medical specialty)

Biology

Microbiology

Gene

Serotype

Genotype

Outbreak

Virology

Pathogenicity

Genetics

Medicine

Molecular epidemiology

International Journal of Molecular Sciences

Infectious bronchitis virus (IBV) variants constantly emerge and pose economic threats to poultry farms worldwide. Numerous studies on the molecular and pathogenic characterization of IBV variants have been performed between 2007 and 2017, which we have reviewed herein. We noted that viral genetic mutations and recombination events commonly gave rise to distinct IBV genotypes, serotypes and pathotypes. In addition to characterizing the S1 genes, full viral genomic sequencing, comprehensive antigenicity, and pathogenicity studies on emerging variants have advanced our understanding of IBV infections, which is valuable for developing countermeasures against IBV field outbreaks. This review of IBV variants provides practical value for understanding their phylogenetic relationships and epidemiology from both regional and worldwide viewpoints.

Infectious Bronchitis Virus Variants: Molecular Analysis and Pathogenicity Investigation