Occurrence of viral haemorrhagic septicaemia virus (VHSV) in wild marine fish species in the coastal regions of Norway

This study was aimed at determining the occurrence of viral haemorrhagic septicaemia virus (VHSV) in selected stocks of wild fish species in the coastal regions of Norway. Six cruises were undertaken covering areas which included the coastal regions of northern Norway, the Norwegian Sea, the Barents Sea, and the Skagerrak area down to the Danish border. Collected, pooled samples of internal organs (kidney, spleen and heart) from 8395 fish were examined for the presence of VHSV by inoculation on BF-2 cells. Identification of virus was performed by a standard ELISA procedure with monoclonal antibody IP5B11, which is specific for the VHSV nucleocapsid protein (N-protein). VHSV was isolated from blue whiting and Norway pout in Skagerrak. No positive samples were detected in the northern coastal regions of Norway, the Norwegian Sea, or the Barents Sea. The findings indicate a very low occurrence of VHSV in the coastal regions of Norway. Geographically, the only positive samples were obtained from fish collected in areas where VHSV has previously been found in different species of fish.