Viral encephalopathy and retinopathy (VER) in Mediterranean wild and farmed fish species: the experience of the Istituto Zooprofilattico Sperimentale of Sicily (Italy)

Abstract

Betanodavirus infection is widespread in a broad spectrum of fish species worldwide. In Italy, it is responsible for outbreaks of Viral Encephalo-Retinopathy (VER) that causes mortality and economic losses in sea fish farming. The infection is also widespread in wildlife, where there are generally no observed clinical manifestations. In this study we report the results obtained from the decennial activity of Istituto Zooprofilattico Sperimentale of Sicily on the research of Betanodavirus infection in wild fish of Mediterranean Sea and in farmed fish. Among the fish species analyzed, Gobius niger (Linnaeus, 1758), Mullus barbatus (Linnaeus, 1758), and Trisopterus minutus capelanus (Lacepède, 1800) were found positive and these could be a reservoir in which the virus can survive for long periods of time. The Betanodavirus isolation from pelagic species such as Pagellus erythrinus (Linnaeus, 1758), Sardina pilchardus (Walbaum, 1792), Lepidopus caudatus (Euphrasen, 1788), Epinephelus marginatus (Lowe, 1834), Epinephelus aeneus (Geoffroy Saint-Hilaire, 1817) resulted interesting because these species could play a more significant epidemiological role, being able to move even at distances.