Betanodavirus or nervous necrosis virus (NNV) is a viral genus classified in the family Nodaviridae. It contains four recognized species: Barfin flounder nervous necrosis virus (BFNNV), Redspotted grouper nervous necrosis virus(RGNNV), Striped Jack nervous necrosis virus (SJNNV) and Tiger puffer nervous necrosis virus (TPNNV), being the SJNNV the type species.