Recombinant characteristics, pathogenicity, and transmissibility of a variant goose orthoreovirus derived from...

Since March 2021, an infectious characterized by white necrotic foci throughout the goose body has appeared in the major goose-producing regions in China. This disease has caused economic hardship for goose farms in many regions of China with approximately 50 % mortality. A novel goose-origin orthoreovirus was isolated from the spleen of diseased geese and designated as N-GRV/HN/Goose/2021/China (N-GRV-HN21) strain. Next-generation sequencing and phylogenetic analysis revealed that the isolate was a reassortant virus containing viral gene segments from three ARV serotypes that infect duck, muscovy duck, and goose. Geese infection test showed that both N-GRV-HN21-infected and contacted geese displayed whole-body white necrotic foci. N-GRV RNA was detected in different organs of both infected and contacted geese, indicating that the N-GRV isolate is pathogenic and transmissible in geese. Seroconversion was also observed in experimentally infected and contacted geese. A prevalence study of 323 goose serum samples collected from different goose breeding areas showed that 86 % of the geese were positive for N-GRV. In conclusion, all results warrant the necessity to monitor orthoreovirus epidemiology and reassortment as the orthoreovirus could be an important pathogen for the waterfowl industry and a novel orthoreovirus might emerge to threaten animal and public health.