Genetic analysis of the S1 gene of 4/91 type infectious bronchitis virus isolated in Japan

• Published in: Journal of Veterinary Medical Science Vol. 71; no. 5; pp. 583 - 588
• Main Authors: Shimazaki, Y.(National Veterinary Assay Lab. Tokyo (Japan)), Watanabe, Y, Harada, M, Seki, Y, Kuroda, Y, Fukuda, M, Honda, E, Suzuki, S, Nakamura, S
• Format: Journal Article
• Language: English
• Published: Japan JAPANESE SOCIETY OF VETERINARY SCIENCE 01.05.2009; Japan Science and Technology Agency
• Subjects: 4/91; 793B; Amino Acid Sequence; Animals; AVIAN INFECTIOUS BRONCHITIS VIRUS; Base Sequence; CHICKENS; Coronavirus Infections - epidemiology; Coronavirus Infections - veterinary; Coronavirus Infections - virology; Disease Outbreaks - veterinary; Genetic Variation; GENOTIPOS; GENOTYPE; GENOTYPES; Infectious bronchitis virus; Infectious bronchitis virus - genetics; Infectious bronchitis virus - isolation & purification; JAPAN; Japan - epidemiology; JAPON; Membrane Glycoproteins - genetics; Membrane Glycoproteins - immunology; Molecular Sequence Data; PCR; POLLO; Polymorphism, Restriction Fragment Length; POULET; Poultry Diseases - epidemiology; Poultry Diseases - virology; Reverse Transcriptase Polymerase Chain Reaction - veterinary; RNA, Viral - chemistry; RNA, Viral - genetics; Sequence Alignment; Specific Pathogen-Free Organisms; Spike Glycoprotein, Coronavirus; VACCIN; vaccine; VACCINES; VACUNA; Viral Envelope Proteins - genetics; Viral Envelope Proteins - immunology; Viral Vaccines - administration & dosage; Viral Vaccines - genetics; Viral Vaccines - immunology; VIRUS BRONCHITE INFECTIEUSE AVIAIRE; VIRUS BRONQUITIS INFECCIOSA AVIAR; Japan
• ISSN: 0916-7250; 1347-7439
• DOI: 10.1292/jvms.71.583

S1 gene sequences for infectious bronchitis virus (IBV) strains of the 4/91 genotype (commonly called 793B) isolated from field outbreaks in Japan were analyzed to ascertain the relationship to 4/91 vaccine strain. Three field isolates (JP/Wakayama/2003, JP/Iwate/2005 and JP/Saitama/2006) from flocks not immunized with a 4/91 type live IBV vaccine and one isolate (JP/Wakayama-2/2004) from a flock immunized with a 4/91 type live vaecine were examined. The amino acid identities among JP/Wakayama/2003, JP/Iwate/2005 and JP/Saitama/2006 were about 98%, whereas the identities to the 4/91 vaccine strain and JP/Wakayama-2/2004 were about 90%. Three of the field isolates, JP/Wakayama/2003, JP/Iwate/2005 and JP/Saitama/2006, were classified into a cluster closely related to French and Spanish isolates, but different from the cluster including the vaccine and JP/Wakayama-2/2004. These results indicate that JP/Wakayama/2003, JP/Iwate/2005 and JP/Saitama/2006 were derived from foreign field isolates, but not from the vaccine strain. On the other hand, the S1 gene of JP/Wakayama-2/2004 revealed high sequence similarity with that of the 4/91 vaccine strain and appeared to be a vaccine-like virus derived from a vaccine. The field isolates of 4/91 genotype IBV could be distinguished from other genotypes by using the Bal I and Pst I enzymes in addition to the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) methods of Mase et al.[16] using Hae II and EcoR I enzymes. Furthermore, the 4/91 vaccine strain and vaccine-like isolate (JP/Wakayama-2/2004) could be differentiated from the other field isolates by Bgl II digestion. This method, therefore, would assist in identification of field isolates of the 4/91 genotype as outbreaks of IBV in vaccinated flocks.