A Novel Genotype of Avian Infectious Bronchitis Virus Isolated in Japan in 2009

Avian infectious bronchitis viruses (IBVs) isolated from commercial layer flocks kept in Ibaraki Prefecture in 2009 were genetically and serologically characterized. Reverse transcription-PCR coupled with direct nucleotide sequencing and GenBank BLAST database analysis of the hypervariable region of the S1 subunit of the virus spike gene showed that these isolates are genetically very different from the previously known IBV genotypes in Japan. Furthermore, none of the antisera used in this study neutralized the index isolate (JP/Ibaraki/168-1/2009) in virus neutralization tests. These results suggest that the isolates are a novel IBV genotype in Japan (designated JP-IV).