Scientists have discovered three new viruses in the endangered Chinook and sockeye salmon populations.
All three of the viruses discovered in the endangered fish have never been discovered in salmon before and all three of them are known to have serious effects on other infected species.
Gideon Mordecai is a researcher at the University of British Columbia’s department of earth, ocean and atmospheric sciences. Mordecai said: “We were surprised to find viruses which had never before been shown to infect fish…Although there’s no risk to humans, one of the viruses is evolutionarily related to respiratory coronaviruses and is localised to the gills. That suggests it has a similar infection strategy to its distant relatives that infect mammals.”
Researchers from the University of British Columbia formed a team with the Fisheries and Oceans Canada researchers in order to conduct research on the fish. The researchers used DNA sequencing, followed by testing each virus. The study screened more than 6,000 salmon from along the British Columbian coast. The research pool also including wild, hatchery and aquaculture fish.
The University of British Columbia virologist, Curtis Suttle, said: “We found the new viruses widely distributed in dead and dying farmed salmon and in wild salmon…It emphasises the potential role that viral disease may play in the population dynamics of wild fish stocks, and the threat that these viruses may pose to aquaculture.”
The virus appeared to spread very quickly in hatcheries and fish farms. One virus appearing in 15% of all hatchery Chinook tested. Additionally, another virus was detected in around 20% of Chinook from fish farm.
Suttle continued: “It’s essential that we determine whether these viruses are important factors in the decline of Chinook and sockeye salmon stocks…The research highlights the need for robust surveillance to improve our understanding of how viruses might impact the health of wild Pacific salmon populations.”