We have seen a lot of irresponsible myths, half-truths and falsehoods this week spreading around the various stories and comments about the “new” virus purportedly found in farmed salmon.
Sadly, most reporters covering this story seem too lazy to ask good questions or research the science for themselves, content instead to craft scary-sounding stories about viruses and possible health scares, because it gets eyeballs on screens and pages.
There are a few things we need to set straight, and hopefully this will be helpful to people who are trying to understand the issue, including the media.
Basic facts about ocean viruses
- Viruses are the most dominant form of life in the ocean, outnumbering even single-celled organisms 10-1.
- Most viruses are benign and are an integral part of the marine ecosystem.
- Fish diseases are not viruses.
- Fish diseases can be caused by viruses, but this is not always the case.
- Fish can carry viruses and be perfectly healthy, with no symptoms of any fish disease.
Basic facts about HSMI
- Heart and Skeletal Muscle Inflammation (HSMI) is a disease of farmed salmon in Norway.
- Piscine Reovirus is a virus which research has linked to the HSMI disease in Norway.
- The HSMI disease has never been observed in B.C. farmed salmon.
- The virus which causes HSMI disease has never been confirmed in B.C. farmed salmon.
Basic facts about ISA
- Infectious Salmon Anemia (ISA) is a disease of farmed salmon in Norway, Eastern Canada, Scotland and Chile.
- ISA disease has been proven to be caused by a particular virus, which scientists call the ISA virus.
- The ISA disease has never been observed in B.C. farmed salmon.
- The ISA virus has never been confirmed in B.C. farmed salmon.
Basic facts about testing for viruses
- Scientists test for viruses using a method known as RT-PCR.
- Fish that die on fish farms, and fish taken as random samples, are tested for a variety of viruses using this method.
- The better-quality the sample, the more confident scientists will be in the test results.
- Even with good-quality samples, RT-PCR results are not enough to confidently state whether or not a virus is present.
- To confirm findings of virus, scientists will run more detailed genetic tests, and will try and grow the suspected virus in a cell culture.
- If they cannot confirm their initial RT-PCR findings, scientists cannot say they have found any virus.
Myths and Facts
Myth: Dr. Kristi Miller found HSMI in farmed Chinook salmon.
Fact: Dr. Kristi Miller found NO evidence of the HSMI disease in farmed Chinook salmon. Using PCR testing, she found the genetic signature of a virus which looks very much like piscine reovirus, which has been linked to the HSMI disease in Norway. However, the fish were not sick in any way that suggested HSMI disease.
Myth: Dr. Kristi Miller found HSMI in wild salmon.
Fact: Dr. Kristi Miller found NO evidence of HSMI in wild salmon. Using PCR testing on wild sockeye samples, she found the genetic signature of a virus which looks very much like piscine reovirus, which has been linked to the HSMI disease in Norway. However, the fish were not sick in any way that suggested HSMI disease.
Myth: Samples of farmed salmon submitted for testing by Alexandra Morton are infected with HSMI.
Fact: There is NO evidence that the fish which were sampled for testing were sick in any way that suggested HSMI disease. What Morton’s samples show, like Miller’s, are that PCR testing reveals the genetic signature of a virus which looks very much like piscine reovirus, which has been linked to the HSMI disease in Norway.
Myth: Eating farmed salmon with HSMI will make people sick.
Fact: None of the fish farmed and sold in B.C. have HSMI disease. And even if they did, eating them would not make people sick. Wild salmon and other wild fish in B.C. are naturally infected with a wide variety of viruses, and people regularly consume wild fish without getting sick from these viruses and diseases in the fish they eat. ALL farmed salmon grown in B.C. follows strict food safety protocols to make sure farmed salmon meets all food safety regulations and guidelines.