Isolation of viral haemorrhagic septicaemia virus (VHSV) from wild marine fish species in the Baltic Sea, Kattegat, Skagerrak and the North Sea

In order to analyse the occurrence of viral haemorrhagic septicaemia virus (VHSV) in the marine environment surrounding Denmark, fish tissue samples were collected on four cruises with the research vessel H/S Dana in 1996 and 1997. The sampling comprised 923 samples totalling 7344 fish representing 29 different species. VHSV was isolated from 24 fish samples from the Baltic Sea, four samples from Skagerrak and three samples from the North Sea. The virus-positive host species included herring Clupeaharengus (11 isolates), sprat Sprattussprattus (eight isolates), cod Gadusmorhua (six isolates), rockling Rhinonemuscimbrius (one isolate), Norway pout Trisopterusesmarkii (one isolate), blue whiting Micromesistiuspoutassou (one isolate), whiting Merlangiusmerlangus (two isolates) and lesser argentine Argentinasphyraena (one isolate). VHSV has previously been reported from cod and herring, but not from the other five species. A virus belonging to serogroup II of the aquatic birnaviruses was isolated from three samples of flounder Platichthysflesus and three samples of dab Limandalimanda and a virus preliminary identified as iridovirus (lymphocystis virus) was isolated from seven samples of long rough dab Hippoglossoidesplatessoides.