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 B.C.’s Broughton Archipelago. The study identified HSMI in five out of seven salmon farms in the region, indicating a more significant occurrence than previously acknowledged. The study also highlights the potential for the disease-causing virus, piscine orthoreovirus (PRV), to spread to wild fish in surrounding waters.
Lead author Emiliano Di Cicco emphasized the need for increased awareness of the disease’s prevalence, citing previous research that had underestimated its impact. This study, which involved examining 749 salmon across the farms, found that nearly seven percent showed signs of HSMI. While the link between PRV and HSMI was previously uncertain, recent experiments have established a definitive connection, prompting calls for the virus to be reclassified as pathogenic by the Department of Fisheries and Oceans (DFO) in B.C.
Di Cicco also urged for standardized diagnostic criteria for HSMI that align with global standards, as current criteria in B.C. may overlook the disease’s chronic nature. The DFO has stated its intent to review the study findings and emphasized the rigorous scientific collaboration behind its diagnostic criteria for HSMI.
The study was conducted in collaboration with several First Nations groups, highlighting the importance of salmon to Indigenous communities in B.C. First Nations leaders expressed gratitude for the scientific validation of their concerns and reiterated the critical role of salmon in their cultural heritage and ecosystem. The study’s findings underscore ongoing debates surrounding open-net fish farming practices in B.C. and their potential impact on wild salmon populations.