First, maybe read what was actually posted before, TB.
If it is indeed VHS it could very well be the North American strain that is already endemic to the Pacific coast and has already been found and described in Pacific Herring. With Pacific Herring the virus appears to be more acutely lethal to juvenile fish than adult fish.
When you say "So it ends up coming from farmed Salmon......" does not tell the whole story because all viruses come from the wild. What happens is that wild fish spread this virus to farmed salmon (similarly to IHNv). Read this paper which describes it:
Molecular epidemiology of viral haemorrhagic septicaemia virus (VHSV) in British Columbia, Canada, reveals transmission from wild to farmed fishhttp://www.int-res.com/articles/dao_oa/d104p093.pdfIt goes hand-in-hand with the paper Chris posted (also a few of the authors are the same).
The paper that Chris posted is one that I had found last night; it suggests farmed Atlantic salmon can develop clinical signs of VHS and it can persist in the tissues for 10 weeks. VHSV-1Va (the strain in question) occurs annually in farmed salmon in BC and is already tested for along with other viruses like ISAv and IHNv. It should also be noted that farmed Atlantic salmon appear to have a low virulence to VHSV-IVa with no evidence of farm to farm spread; however, it does not mean we should not understand this virus more and it's possible implications to wild fish (the same way it can be transmitted to farmed fish from an epizootic VHSV event from herring or sardines). Understanding also applies to activists/biologists.
One thing that needs to be taken away from this work (that Morton will never tell you) is that it is not entirely clear what drives these outbreaks. This goes for many viruses. There are likely multiple factors at play that interact with the virus to determine how it will impact its host. Certain environmental conditions or food availability are possible triggers. Within those two, environmental conditions could impact food availability. If you read the paper I posted it references 2 studies where VHSV susceptibility in Pacific Herring was highly influenced by diet and temperature. There is more to it than implying that Atlantic Salmon have VHSV and must be spreading it all over the place. This is what the author are trying to convey. What also needs to be mentioned is what is currently done to reduce the potential risk of transmission on fish farms in BC which includes routine testing for VHSV on dead found in pens. Large scale marine die-offs involving VHSV-1Va are not commonly found where this virus exists. This and more is discussed in the report I posted.
As for Morton not receiving a timely response I am not sure why; however, I realize that there are not a lot of staff involved in testing fish health samples - and those dedicated staff members are busy with other samples from enhancement facilities and PIPs (Public Involvement Programs) on a very tight budget. To test samples is not cheap as Morton points out. Well, it is not cheap either for people in government. Nonetheless, it would seem reasonable to me to provide Ms Morton some response in a timely fashion instead of letting this linger because what inevitably happens are multiple blog responses from farm critics accusing the department of hiding information. In actual fact it is more than likely a combination of poor communication by agencies and lack of resources to investigate every sample submitted. Biologists like Morton also have responsibilities also in this. Being described as a "BC Marine Biologist" in the article, Ms Morton should describe what is known about VHSV-1Va (sort of like I did) in order to provide the public with as much information as possible - not just have the public fixated on the story about "Bleeding Herring".
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Topic: Bleeding Herring (Read 11772 times)