Wikipedia
Betanodavirus
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), SJNNV being the type species. There are other 12 tentative species in the genus that haven't been recognized by the ICTV. Betanodaviruses cause a disease in fish called viral nervous necrosis (VNN) or viral encephalopathy and retinopathy (VER).