Attenuated Asian Koi Herpesvirus Strain (SS09 Δ56-57) Shows Promise as a Vaccine Candidate: A Study on Immunogenicity, Safety, and Efficacy

Dear Editor,

Please consider our research article, 'Attenuation of an Asian Koi Herpesvirus Strain through Deletion of ORF56-57: Implications for Vaccine Development,' for publication in Aquaculture.

Koi herpesvirus (KHV) infection causes high mortality in koi and common carp, significantly impacting the aquaculture industry. Our study focuses on an Asian KHV strain, SS09, and the development of a potential attenuated vaccine through the deletion of open reading frames 56 and 57 (ORF56-57).

We successfully generated a mutant strain, SS09 Δ56-57, using homologous recombination technology. This mutant exhibited reduced viral replication in common carp brain (CCB) cells and caused no mortality in infected koi, compared to the near 100% mortality rate of the wild strain.

To evaluate SS09 Δ56-57 as a vaccine candidate, we conducted immersion immunization trials with three different doses. Remarkably, the vaccinated fish showed a relative percentage survival (RPS) ranging from 70.0% to 96.6% after challenge with the wild-type virus. We also observed a dose-dependent response in serum neutralizing antibody titers.

Our findings highlight the potential of SS09 Δ56-57 as a safe and effective vaccine candidate against KHV. The mutant strain's attenuated phenotype, combined with its ability to induce robust immune responses, makes it a promising solution for controlling KHV in aquaculture settings.

We believe our research significantly contributes to aquaculture and aligns with the scope of Aquaculture. Thank you for considering our manuscript.

Sincerely,[Your Name]