en تخصصي Special مروری Review article Viral Nervous Necrosis (VNN) causes viral encephalopathy and retinopathy (VER), a hazardous and devastating disease of many species of cultured and marine fish worldwide. It caused by betanodaviruses a serious concern especially in the fry and young fish. This virus infects most of the cultured fishes causing severe mortality. Our current review focuses chiefly on recent studies performed on VNN disease. Recent outbreaks have been reported in China, Indonesia, Singapore and India, affecting the mariculture and aquaculture industry. It also decreased dramatically Mullet stocks in the Caspian Sea. The four main genotypes of VNN were found in all continentals’ except South America. The economic loss due to the virus is mainly due to mortality and spread of infection both vertically and horizontally. Our investigation in recent years suggest that more research and epidemiological surveys should be conducted, especially in critical areas were mariculture farms are planned to be established. Therefore, finding new rapid diagnosis tools, Monitoring and Surveillance program, and effective vaccines, Control, Prevention and Eradication in the comprehensive program should be considered globally. Viral Nervous Necrosis, fish, Mariculture 42 57 http://journal.isv.org.ir/browse.php?a_code=A-10-242-1&slc_lang=en&sid=1 Mohammad Jalil Zorriehzahra zorrieh@yahoo.com 10031947532846007081 10031947532846007081 No Scientific Information and Communication Dept.., Iranian Fisheries Science Research Institute (IFSRI), Agricultural Research Education and Extension Organization (AREEO), Tehran, I.R. Iran Fatemeh Hassantabar f.hassantabar66@gmail.com 10031947532846007082 10031947532846007082 No Department of Fisheries Science, Sari Agricultural Sciences and Natural Resources University, Sari, Mazandaran, I.R. Iran Mina Ziarati mziarati2@gmail.com 10031947532846007083 10031947532846007083 Yes Department of Microbiology, Islamic Azad University, Jahrom Branch, Jahrom, I.R.Iran Laleh Yazdanpanah Goharrizi l_yazdanpanah@yahoo.com 10031947532846007084 10031947532846007084 No Animal Sciences Research Department, Kerman Agricultural Research and Education Center, Agricultural Research Education and Extension Organization (AREEO), Kerman, I.R.Iran Masoud Seidgar seidgar21007@yahoo.com 10031947532846007085 10031947532846007085 No National Artemia Research Center, Iranian Fisheries Science Research Institute, Agricultural Research, Education and Extension Organization, Urmia, I.R.Iran Kouros Radkhah kourosradkhah@gmail.com 10031947532846007086 10031947532846007086 No Aquatic Animal health & Diseases Dept., Iranian Fisheries Science Research Institute (IFSRI), Agricultural Research Education and Extension Organization (AREEO), Tehran, I.R. Iran Mohammad Sheikh Asadi m.sh_asadi73@yahoo.com 10031947532846007087 10031947532846007087 No Animal Sciences Research Department, Kerman Agricultural Research and Education Center, Agricultural Research Education and Extension Organization (AREEO), Kerman, I.R.Iran