Picornaviruses of Fish

Picornaviruses of fish belong to the family Picornaviridae. Fish picornaviruses are single stranded, positive-sense RNA viruses with a genome of 7.0 to 9.0. kb in length. This rapidly growing group of viruses affects a wide range of ray-finned fish species (class Actinopterygii) from marine and freshwater environments around the world. Clinical signs range from apparently healthy to hemorrhage at the base of fins and diffuse hemorrhage of the skin. Multiple picornaviruses have been associated with mortality in fish hosts. Fish picornaviruses can be detected with classical methods such as electron microscopy, virus isolation and immunofluorescence, as well as molecular techniques. Recently, these viruses have been characterized by molecular analysis based on Sanger sequencing and next-generation sequencing. Little is known about the epidemiology and disease causing potential of many fish picornaviruses, thus proactive measures to prevent or control these viruses is warranted.