Viral hemorrhagic septicemia virus (VHSV),belonging to the genus Novirhabdovirus,Rhabdoviridae family,is a causative agent of high mortality in fish and has caused significant losses to the aquaculture industry.Currently,no effective vaccines,Food and Drug Administration-approved inhibitors,or other therapeutic intervention options are available against VHSV.α-Lipoic Acid (LA),a potent antioxidant,has been proposed to have antiviral effects against different viruses.In this study,LA (CC50 =472.6 μmol/L) was repurposed to exhibit antiviral activity against VHSV.In fathead minnow cells,LA significantly increased the cell viability post-VHSV infection (ECso =42.7 μmol/L),and exerted a dose-dependent inhibitory effect on VHSV induced-plaque,cytopathic effects,and VHSV glycoprotein expression.The time-of-addition assay suggested that the antiviral activity of LA occurred at viral replication stage.Survival assay revealed that LA could significantly upregulated the survival rate of VHSV-infected largemouth bass in both co-injection (38.095％ vs.1.887％,P ＜ 0.01) and post-injection manner (38.813％ vs.8.696％,P ＜ 0.01) compared with the control group.Additional comparative transcriptome and qRT-PCR analysis revealed LA treatment upregulated the expression of several antiviral genes,such as IRF7,Viperin,and ISG15.Moreover,LA treatment reduced VHSV-induced reactive oxygen species production in addition to Nrf2 and SOD1 expression.Taken together,these data demonstrated that LA suppressed VHSV replication by inducing antiviral genes expression and reducing VHSV-induced oxidative stress.These results suggest a new direction in the development of potential antiviral candidate drugs against VHSV infection.