ANNEX 8
Map 8.8 - The geographical distribution of marine VHS-like virus
Introduction.
Marine Viral Haemorrhagic Septicaemia (VHS) is a disease closely related to VHS known from freshwater rainbow trout farming, in which it causes severe disease outbreaks with high mortality. In 1988, the VHS virus was isolated for the first time from ascending Pacific salmon species. In contrast to the freshwater VHS, the marine isolates appeared to be apathogenic to rainbow trout. Further classification has revealed that the marine VHS is genetically different from the freshwater type.
The marine VHS has so far been isolated from eight different fish
species in the USA and Canadian Pacific waters and
in fourteen species in the North Sea and adjacent waters.
Reports from the USA suggest that marine VHS virus may be involved in
epizootics in Pacific herring. The European investigations have shown
relatively high prevalences of the virus in herring and sprat in the
Baltic Sea.
Outbreaks of marine VHS have been observed in turbot produced
in aquaculture facilities in Europe and the widespread spatial distribution
of the virus in the marine environment may constitute a potential threat
to the aquaculture industry.
Map 8.8. The geographical distribution of marine VHS-like virus
The map illustrates the areas investigated since 1988 for the presence of the marine VHS-like virus (light grey shading) and the areas where VHS-like virus has been isolated (dark grey).
Source of data: Published literature and EU reports.