Molecular Characterization of Emerging Gyrovirus galga 1 from Poultry Markets of Guangxi, China

Gyrovirus galga 1 (GyG1) can infect a variety of animals and humans, but prevention and control strategies are limited, which endangers the healthy development of the poultry breeding industry and has a potential impact on public health safety. The live poultry market (LPM) connects the production and consumption ends, and the pathogen may spread across regions through transportation and personnel flow. To understand the prevalence of GyG1 in Guangxi, 3482 samples from LPMs, namely, 2693 chicken throat and cloacal swabs and 789 environmental samples collected in Guangxi from December 2019 to December 2024, were assayed by PCR. The results revealed that GyG1 was present in chicken and environmental samples from LPMs in Guangxi, China, with positivity rates of 17.08% and 13.31%, respectively. Eight GyG1-positive samples were randomly selected, including 5 chicken swab samples and 3 environmental samples for whole-genome amplification. The amino acids encoded by the three ORFs were analysed, and some mutation sites unique to these 8 variants were found. The homology between the 8 GyG1 genomes and 36 reference sequences was 96.8-99.8%. The homology of the VP1 gene sequence was 96.5-99.9%, and the homology of the amino acid sequence was 99.4-100%. A phylogenetic tree was constructed on the basis of the 8 GyG1 genomes and 36 GyG1 reference genome sequences from 14 different species (8 from zoos) in this study. The 44 sequences were divided into three branches constituting groups A, B and C, with the 8 novel strains classified into group A2. Recombination analysis predicted that two recombination events in the GyG1 sequence were associated with the emergence of Guangxi strain GX-AGV2-202109-5. This study clarified the prevalence and molecular characteristics of GyG1 in LPMs in Guangxi, China, were clarified for the first time, providing important data supporting the prevention and control of GyG1 infection and providing a reference for further understanding the epidemiology and genetic diversity of GyG1.