Effect of NNV on cellular ROS production and the antiviral activity of oxygen radicals. A ROS production by head kidney leukocytes during in vitro infection with NNV. The data are represented as the fold change relative luminescence units (RLUs) in the infected samples compared to those of the uninfected cells at each sampling point. Statistically significant differences between NNV-infected and control cells were represented with #, whereas differences along time for the infected cells were represented with *. B ROS detection in head kidney leukocytes at 1 and 5 dpi after in vivo infection with NNV. The data are represented as the fold change of the RLUs in the infected fish compared to those measured for the uninfected animals. C Replication levels of NNV after treatment with H2O2 measured by qPCR amplification of the gene encoding the NNV capsid. hpt: hours post-treatment.