New Phage in Town: Novel Vibriophage—vB_VibS_KarBoss for Targeted Control of Vibriosis in Aquaculture Amid Climate Change

Antibiotic-resistant Vibrio species pose a threat in aquaculture. This study evaluates the potential of phage vB_VibS_KarBoss under climate-influenced water conditions such as temperature, pH, and salinity. vB_VibS_KarBoss, isolated from fish market wastes, inhibited 48 of 89 nonredundant autochthonous Vibrio isolates. With a 10-min latent period and a burst size of 3 phages per cell, vB_VibS_KarBoss inhibited the growth of pathogenic species including Vibrio campbellii and Vibrio parahaemolyticus . With only 16.4% intergenomic similarity to related phages, we propose a new phage genus, KarBossvirus , for consideration by the International Committee on Taxonomy of Viruses. Considering the robustness of Artemia and their sensitivity to changes in environmental conditions, the virulence of the Vibrio isolates resulting in Artemia mortality and the efficacy of vB_VibS_KarBoss in these altered water conditions were studied. Results support the potential importance of vB_VibS_KarBoss in biocontrol in its ability to rescue >50% Artemia ( p < 0.01) from mortality due to vibriosis.