Interim Report of the Working Group on Pathology and Diseases of Marine Organisms (WGPDMO)

The agenda included several topics related to diseases and pathology in wild and farmed fish and shellfish.The group produced a report on new disease trends in wild and farmed fish and shellfish in the ICES area based on national reports from fifteen member countries. Notable re-ports for wild fish included first observations of salmon gill poxvirus in Canada and pis-cine reovirus in Denmark; the first observation of Vibrio anguillarum serotype O3 in Sweden; disease associated with oomycetes in Russia and Sweden; and prevalences of Pseudoterranova decipiens infection in the northern Baltic Sea that were unexpectedly low given the high prevalences in the southern Baltic. Reports for farmed fish included the first observation of piscine orthoreovirus in Ireland and range expansion of salmonid rickettsial septicaemia in western Canada. Additionally, wrasse and lumpfish cultured as cleaner fish for salmonid aquaculture were noted to be affected by bacterial diseases. Salmon louse control to minimize risk to wild fish poses an ongoing challenge to salmon aquaculture in the ICES region. In shellfish, observations for Pacific oysters included the association of Vibrio aestuarianus with significant mortality in Ireland, the detection of Haplosporidium costale in England representing a first record in Europe, and the detection of a Marteilia not identified to species in France. Marteilia cochillia is an important emerg-ing concern, causing significant disease and mortality in cockles in Spain.