Co-circulation of three clusters of 793/B-like avian infectious bronchitis virus genotypes in Iranian chicken flocks

Kalokhoran, Ali Yousefzadeh; Ghalyanchilangeroudi, Arash; Hosseini, Hossein; Madadgar, Omid; Karimi, Vahid; Hashemzadeh, Masoud; Hesari, Parvaneh; Zabihi Petroudi, Mohammad Taha; Najafi, Hamideh

Avian infectious bronchitis (IB) is an acute and highly contagious viral disease causing severe economic losses in the poultry industry. The 793/B IB virus is an important infectious bronchitis virus (IBV) genotype currently circulating in several countries, including Iran. One hundred confirmed IBV samples (between 2014 and 2015; from 15 provinces in Iran) were selected for genotyping based on S1 sequencing. After phylogenetic analysis, it was found that 30% of the IBV isolates belonged to the 793/B genotype. Results showed that the Iranian 793/B-like IBV isolates could be divided in to three clusters: 4/91-like (50%), 1/96-like (40%), and IB88-like (10%). The sequence similarity between Iranian 793/B-like IBV isolates is 87.69%–100%. The highest identity is between the 4/91 and IB88 clusters (96.38%), and the lowest similarity is between the 1/96 and IB88 clusters (87.62%). This study provides a comprehensive analysis of 793/B-type IBV in Iran and characterization of IBV molecular epidemiology in the country.