Abstract

Simple SummaryA novel strain of the Chinese rice field eel rhabdovirus (CrERV) was found in a new city, designated as CrERV-XT. Comprehensive genomic characterization and phylogenetic analysis revealed that CrERV-XT shares 94.39% the complete genomic sequence identity with the index strain CrERV. Notably, it exhibits more genetic mutations compared to all previously characterized CrERV variants. This study enriches the pathogenic data of CrERV and provides a basis for further research into the evolution and transmission of it. Moreover, amino acid sequence alignment and antigenic epitope prediction in this study may provide useful reference and theoretical support for future research on antigen screening and prevention strategies against CrERV.Chinese rice-field eels (Monopterus albus) are a commercially farmed freshwater fish species in China. In recent years, the rapid expansion of aquaculture has been accompanied by frequent outbreaks of viral diseases, posing a serious threat to the sustainability of the Chinese rice-field eel farming industry. In this study, a rhabdovirus strain was isolated from diseased Chinese rice-field eels at a farm located in Xiantao, Hubei Province, China. Although the complete genomic sequence of CrERV-XT showed higher identity to the infectious hemorrhagic syndrome virus (IHSV) (96.16%) than to CrERV (94.39%), phylogenetic analysis based on the L protein placed CrERV-XT within the same clade as CrERV, supporting its tentative classification as a novel variant of CrERV. Furthermore, the amino acid sequence of the L protein showed greater similarity to that of CrERV (97.89%) than to IHSV, while the N, P, M and G proteins exhibited higher homology with their counterparts in IHSV. CrERV-XT displayed considerable genetic divergence from known CrERV isolates, which is presumably attributed to its geographic isolation in different locations. Alignment of the G protein sequences from five strains (CrERV-XT, CrERV, CrERV-TYY25, CrERV-XY0907 a