Genetic and structural factors contributing to the dominance and persistence of goose astrovirus type 2

Goose astrovirus type 2 (GoAstV-2) became the dominant strain in China post-2017.GoAstV-2 exhibits weaker codon usage bias, enhancing adaptability across hosts.The stability of GoAstV-2 spike protein reduces mutation needs and selective pressure.GoAstV-2 low spike protein variability supports long-term persistence in host populations.