A fresh study from the Pacific Salmon Foundation reveals that viral heart disease is more prevalent in open-net salmon farms in British Columbia than previously acknowledged. The research, published in the Aquaculture journal, identified heart and skeletal muscle inflammation (HSMI) in five out of seven open-net pen salmon farms located in the Broughton Archipelago near Vancouver Island’s Port McNeill. Researchers highlight the potential risk of the disease-causing virus, piscine orthoreovirus (PRV), spreading to wild fish in the surrounding waters.
Lead author Emiliano Di Cicco emphasized that the occurrence of the disease is significantly higher than previously estimated. This new study contrasts with earlier research in 2017 that only detected the disease in one out of four farms. Di Cicco stressed the importance of recognizing the wider impact of the disease and urged government authorities to reassess the classification of PRV as a pathogenic virus.
The Department of Fisheries and Oceans (DFO) in British Columbia currently categorizes PRV as non-pathogenic, despite evidence linking it to HSMI in Pacific salmon. Di Cicco advocates for aligning diagnostic criteria with international standards to improve disease identification. The global perspective views HSMI as a chronic, ongoing condition, challenging the current diagnostic methods employed by DFO.
DFO announced plans to review the study findings and incorporate them into future assessments. The agency emphasized the collaborative development of diagnostic criteria with scientific experts to maintain global alignment and scientific rigor. The B.C. Salmon Farmers Association has not responded to requests for comment, though industry groups have defended salmon farming as a critical contributor to the local economy and a significant source of Canadian salmon production.
The study was conducted in collaboration with the Mamalilikulla, ʼNa̱mǥis, and Ḵwiḵwa̱sut’inux̱w Ha̱xwa’mis First Nations, underscoring the significance of salmon to Indigenous communities along the coast of British Columbia. First Nations leaders expressed concerns over the impact of open-net pen salmon farms on salmon populations and the environment, highlighting the need for greater conservation efforts to protect this vital resource.