The antiviral Mx protein coding gene was also upregulated after infection in prime- and booster-vaccinated fish at 7 dpc, but the induction was only maintained at 30 dpc in booster-vaccinated individuals in which the viral load showed the highest difference with the control group, supporting that Mx is involved in the control of NNV replication, as previously reported in grouper [59]. The gene discussed is MX1; the disease is infection.