Molecular Characterization and Pathogenicity Analysis of Novel Goose Parvovirus Isolated in Shandong Province Provide Insights into Viral Epidemic Tendency and Genetic Basis for Cross-Species Transmission and Pathogenicity Attenuation

The novel goose parvovirus (NGPV), an agent of short beak and dwarfism syndrome (SBDS), has been circulating in China since 2015; however, the absence of systematic genetic evolution and diversity analysis has limited our understanding of the viral epidemic tendency and genetic basis for cross-species transmission and pathogenicity attenuation. In this study, five NGPVs were isolated in 2022-2023, and their genomes were sequenced. A comprehensive analysis of genetic evolution and diversity was conducted using sequences of representative waterfowl parvoviruses isolated at different periods. Subsequently, pathogenicity and sero-response studies in ducks were also conducted. The results indicated that circulating NGPV in China could be divided into two genotypes and two subtypes and three epidemic phases from evolutionary and temporal dimensions, respectively. Currently, NGPV Ia is the dominant genotype across China. Phylogenetic analysis demonstrated that VP1 was the leading factor in viral evolution. The genetic diversity analysis showed regular mutation sites in both proteins. According to their location and resultant structural changes, combining the results of pathogenicity and humoral immune response, several substitutes are possibly latent residues for the virus to achieve cross-host infection, escape from antibody recognition, and undergo pathogenicity alteration. The findings of this study provide novel insights into the viral epidemic tendency and genetic basis for cross-species transmission and pathogenicity attenuation and will help to facilitate the development of vaccines and antiviral therapy.