A recent study by the Pacific Salmon Foundation reveals a higher prevalence of viral heart disease, specifically heart and skeletal muscle inflammation (HSMI), in open-net salmon farms in British Columbia’s Broughton Archipelago than previously acknowledged. The research identified HSMI in five out of seven open-net pen salmon farms in the region, east of Port McNeill on Vancouver Island. The study also highlights the potential transmission of the disease-causing virus, piscine orthoreovirus (PRV), from farmed fish to wild fish in the surrounding waters.
Lead author Emiliano Di Cicco emphasized that the occurrence of HSMI is more significant than previously believed, contrary to earlier assumptions. Previous research in 2017 had already detected the disease in one out of four farms, indicating an ongoing issue rather than an isolated case.
The Department of Fisheries and Oceans (DFO) is reassessing the findings of the study. The study found that nearly seven percent of the 749 examined salmon exhibited signs of HSMI. While the disease’s link to PRV was uncertain in the past, recent experiments by Norwegian researchers confirmed the association.
Di Cicco advocated for reclassifying PRV as a pathogenic virus and aligning diagnostic criteria with international standards. He argued that the current classification by DFO as non-pathogenic overlooks the potential harm to Pacific salmon, which can suffer from various health issues when infected by PRV, including anemia, heart inflammation, liver and kidney damage, and jaundice.
The study’s collaboration with First Nations groups, including the Mamalilikulla, ʼNa̱mÇ¥is, and Ḵwiḵwa̱sut’inux̱w Ha̱xwa’mis communities, underscores the importance of supporting salmon populations for Indigenous communities. Chief Rick Johnson and Chief Councillor Don Svanik emphasized the cultural significance of salmon and the need to protect these vital species for both the environment and the Indigenous way of life.