Full-length genome reveals genetic diversity and extensive recombination patterns of Saudi GI-1 and GI-23 genotypes of infectious bronchitis virus

Virology Journal, Journal Year: 2025, Volume and Issue: 22(1)

Published: Jan. 4, 2025

Despite numerous genetic studies on Infectious Bronchitis Virus (IBV), many strains from the Middle East remain misclassified or unclassified. Genotype 1 (GI-1) is found globally, while genotype 23 (GI-23) has emerged as predominant in region, evolving continuously through inter- and intra-genotypic recombination. The GI-23 now enzootic Europe Asia. Over a 24-month period May 2022 to June 2024, 360 samples were collected 19 layer 3 broiler poultry farms central Saudi Arabia. chickens exhibited reduced laying rates symptoms such weakness respiratory distress, broilers showed issues. Samples, including tracheal swabs various tissue specimens, pooled, homogenized, stored at -20 °C prior PCR analysis. underwent virus isolation embryonated chicken eggs, RNA extraction using automated systems, detection of IBV real-time RT-PCR targeting conserved 5'-UTR fragment. Full-length genome sequencing was performed, recombination analysis conducted RDP 4.6. cluster into genotypes GI-1 GI-23.1. study identified critical amino acid substitutions hypervariable regions spike protein detected events ORF1ab, N, M, 3ab, 5ab genes, with nsp3 ORF1ab showing greatest number events. multiple that different genes indicate circulating do not share single ancestor but have successive

Language: Английский

Revealing a novel GI-19 lineage infectious bronchitis virus sub-genotype with multiple Recombinations in South Korea using whole-genome sequencing

Infection Genetics and Evolution, Journal Year: 2025, Volume and Issue: 128, P. 105717 - 105717

Published: Jan. 18, 2025

Infectious bronchitis (IB), caused by the infectious virus (IBV), is a highly contagious chicken disease, causing economic losses worldwide. New IBV strains and variants continue to emerge despite using inactivated live-attenuated vaccines prevent or control IB. In this study, S1 genes of 46 strains, isolated from commercial flocks between 2003 2024 in Korea were sequenced genetically characterized. The isolates belonged Korean group II (K-II), which was included GI-19 lineage. K-II divided into five sub-genogroups (a-e) based on phylogenetic tree analysis results nucleotide identification gene. Of these, K-IId most common genotype Korea; however, eight novel belonging K-IIe sub-genotype discovered. amino acid identities other four sub-genotypes 84.42-95.89 % 84.02-95.86 %, respectively. complete genomes obtained next-generation sequencing. Various recombination patterns observed high homology gene among strains. Among isolates, six recombinants, exhibiting recombinations K-IIc, K-IIa, with live vaccine strain. Most breakpoints detected nsp2 region ORF1a, S2, M genes. present study proposed new classification criteria for lineage prevalent South revealed recently identified providing important information viral evolution.

Language: Английский