Porcine epidemic diarrhea viruses (2022-2023) in Northern Vietnam: revealing a new subgenogroup (G2e) to emerge in pigs.

Abstract

We present evidence supporting the identification of a subgenogroup of emerging Porcine epidemic diarrhea viruses (PEDVs) (2022-2023) in six provinces in Central and Northern Vietnam. It is proposed as a new subgenogroup G2e. This group has nine sites with unique amino acid variations and is phylogenetically different from previously identified ones. They are genetically associated with Chinese Guangxi-PEDV strains, which indicate a plausible emerging origins. The between-group mean genetic distances estimated between these and strains of typical subgenotypes (G1a, G1b, G1c, G1d, G2a, G2b, G2c, G2d, and G3) were significant, furthermore substantially distinguishing them from other subgenogroups. Our findings contribute to a better understanding of PEDV diversification, notably the recently isolated G2 strains that appeared in the 2010s as well as the complicated co-circulation and evolution of numerous (sub)genotype strains in Vietnam.