Evaluation of a Low-Temperature Immersion Immunization Strategy for the Infectious Spleen and Kidney Necrosis Virus Gene-Deleted Attenuated Vaccine.

Background: Infectious spleen and kidney necrosis virus (ISKNV) poses a significant threat to aquaculture sustainability, particularly affecting mandarin fish () and causing significant economic losses.

Methods: To address this challenge, this study developed an ISKNV Δ vaccine strain, where the gene was knocked out. Infection assays conducted at 28 °C showed that the knocking out the gene decreased the virulence of ISKNV and reduced lethality against mandarin fish by 26.