A recent study conducted by the Pacific Salmon Foundation has revealed a higher prevalence of viral heart disease, known as heart and skeletal muscle inflammation (HSMI), in open-net salmon farms in the Broughton Archipelago of British Columbia. The research found HSMI in five out of seven salmon farms in the region, indicating a more widespread occurrence than previously believed. The study also highlighted the potential for the disease-causing virus, piscine orthoreovirus (PRV), to spread from farmed fish to wild fish in the surrounding waters.

Lead author Emiliano Di Cicco emphasized that the study’s findings challenge previous assumptions about the disease’s prevalence in open-net fish farms off the coast of British Columbia. The research, which involved examining 749 salmon across the farms, showed that nearly seven percent exhibited signs of HSMI.

While the Department of Fisheries and Oceans (DFO) in British Columbia currently categorizes PRV as non-pathogenic, Di Cicco urged the government to reclassify the virus as pathogenic. He also called for aligning diagnostic criteria for HSMI with global standards, citing discrepancies in how the disease is diagnosed in Canada compared to other countries.

In response to the study, DFO stated that it would review the findings and incorporate them into future assessments. The agency emphasized that detecting a virus in farmed fish does not automatically imply negative impacts on wild salmon populations and highlighted the collaboration with scientific experts to establish diagnostic criteria for HSMI.

The study, conducted in collaboration with several First Nations groups, has drawn attention to the longstanding concerns about the environmental impact of open-net pen salmon farms. Indigenous leaders expressed gratitude for the scientific validation of their observations and reiterated the importance of protecting salmon populations for both cultural and ecological reasons.