Talk:NNV

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Nodavirus

Viral nervous necrosis (VNN, Yoshikoshi & Inoue 1990) disease by fish nodavirus, caused by a virus from the Betanodaviridae family is characterized by viral encephalopathy and retinopathy (VER, Office International des Epizooties 2000). It has been identified in more than 30 marine fish species from 14 families of fishes causing massive mortalities and economic loss worldwide in marine aquaculture production (Munday and Nakai, 1997; Fukuda et al., 1996; Grotmol et al., 1997; Le Breton et al., 1997, Skliris and Richards 1999, Ikenaga et al., 2002). This disease is characterised by abnormal swimming behaviour, vaculating lesions in the brain and retinal tissue of the infected fish and frequently leads to death, especially in larval and juvenile fish.. The virus responsible for causing VNN is composed of two single stranded, positive sense without poly (A), non-enveloped and the size ranging from 25-30 nm (Mori, Nakai, Muroga, Arimoto, Mushiake & Furusawa 1992; Comps, Pepin & Bonami 1994). RNA1 encodes for RNA-dependent RNA polymerase and RNA2 encodes for the structural capsid protein The coat protein is encoded by (Comps et al., 1994; Delsert et al., 1997; Nishizawa et al., 1994). They are the causative agents of viral nervous necrosis (VNN) disease in marine species in many countries (Renault et al., 1991; Mori et al., 1992; Chua et al.,1994; Chi et al.,1997; Grotmol et al.,1997; Bovo et al., 1999; Cutrín et al., 2007).