A recent study by the Pacific Salmon Foundation revealed that viral heart disease, specifically heart and skeletal muscle inflammation (HSMI), is more prevalent in open-net salmon farms in British Columbia than previously acknowledged. The research, published in the journal Aquaculture, identified HSMI in five out of seven open-net pen salmon farms located in the Broughton Archipelago near Vancouver Island. The study highlighted the presence of the disease-causing virus, piscine orthoreovirus (PRV), which can potentially spread to wild fish in the surrounding waters.
Lead author Emiliano Di Cicco emphasized that the actual occurrence of the disease surpasses earlier estimations, based on their findings. Previous research in 2017 also indicated the presence of the disease in farmed salmon, raising concerns about the transmission of diseases to wild salmon populations. The study further found that nearly seven percent of the examined salmon across the farms displayed signs of HSMI.
While the Department of Fisheries and Oceans (DFO) in British Columbia currently classifies PRV as non-pathogenic, Di Cicco urged for a reevaluation, advocating for a shift to categorize the virus as pathogenic. He highlighted discrepancies in diagnosing HSMI, emphasizing the need for aligning diagnostic standards with global practices to better detect the chronic, low-level condition.
The DFO assured that it would review the study’s findings for future considerations. It emphasized the collaborative establishment of diagnostic criteria with scientific experts to ensure alignment with global standards. Meanwhile, the B.C. Salmon Farmers Association refrained from immediate comments on the study but had previously dismissed concerns about PRV as “fearmongering,” emphasizing the importance of salmon farming for job creation and Canada’s salmon production.
The study also highlighted collaboration with First Nations communities, with leaders expressing long-standing concerns about the impact of open-net pen salmon farms on salmon populations and the environment. The partnership with Indigenous groups underscored the significance of supporting salmon, a vital aspect of the coastal Indigenous culture and ecosystem in British Columbia.