2026-10-14T16:47:43Z https://www.scidb.cn/oai

10.57760/sciencedb.40423 2026-08-12T10:44:58Z

2026-08-12 Avian reovirus genotype VI is a newly emerged pathogen causing multiple immune organs damage and arthritic tropisms in chicks doi:10.57760/sciencedb.40423 en Recent studies have shown that conventional avian reovirus (ARV) vaccines based on the S1133 (Genotype I) strain fail to provide effective protection against emerging ARV variants. Strains of different genotypes continue to be isolated from immunized chicken flocks exhibiting clinical signs. In this study, two genotype VI ARV variants, GZ25 and JJ615, were isolated from chickens exhibiting clinical symptoms. Transmission electron microscopy revealed that the viral particles were regular spheres with a distinctive double-layered capsid structure resembling a “tire” or “garland.” Indirect immunofluorescence assays demonstrated that the GZ25 strain exhibited significant reactivity with polyclonal antibodies targeting ARV σC and σB proteins. Phylogenetic analysis confirmed that GZ25 and JJ615 belong to a novel ARV genotype VI variant. Whole-genome analysis indicated that the σC amino acid sequences of these strains differ significantly from other genotypes and exhibit low conservation. The σC protein of these isolates shares only 48% amino acid identity with the S1133 vaccine strain. Animal challenge experiments confirmed that ARV genotype VI can induce typical clinical signs and pathological lesions in chicks and is highly pathogenic. Furthermore, inoculation experiments of SPF chicken embryos with the new ARV variant strain have, for the first time, demonstrated that newly hatched chicks develop pronounced symptoms of arthritis, indicating a high risk of vertical transmission. These findings underscore the urgent need to develop updated vaccines that are immunologically matched to emerging ARV variants in order to effectively control avian diseases. Avian reovirus (ARV) variants; Genotype VI; Whole-genome; Highly pathogenic Quansheng Chen PUBLIC https://creativecommons.org/licenses/by/4.0/ dataset Science Data Bank