An entire stock of salmon at a fish farm in Culloden Point has now been culled following a confirmed outbreak of infectious haematopoietic necrosis (IHN) virus. The area is located beyond Saltery Bay in Jervis Inlet.
The farm's owner, Grieg Seafood Ltd., had been keeping its stock of 316,000 under voluntary quarantine since the announcement of a preliminary positive result on Thursday, Aug. 2. Routine testing by staff revealed the initial cause for concern and more extensive tests by the Canadian Food Inspection Agency (CFIA) confirmed the outbreak late Tuesday, Aug. 7.
"The farming team was disappointed and saddened by this issue and outcome,"stated Grieg Seafood's managing director Stewart Hawthorn in an email to the media Friday, Aug. 10, "but was pleased that this was dealt with quickly and in a responsible manner, overseen and approved by the Canadian Food Inspection Agency."
CFIA had issued a disposal notice for all stock of the farm. The agency worked with farm staff to develop a removal plan, one that requires CFIA approval before implementation.
"We appreciate the agency's swift and efficient handling of this situation and welcome the opportunity to resolve this quickly and thoroughly," Hawthorn wrote. "Based on last week's preliminary positive result, this confirmation was not unexpected. Such early and swift detection and action is evidence of the effectiveness of our fish health monitoring system and our responsible approach to fish farm management."
The company has checked the health of stocks at all of its farms on numerous occasions over the last two months. More than 1,500 fish have been individually assessed and no other incidents of IHN have been detected. Other salmon farms in the area are not believed to be currently at risk or to have been affected as a direct result of the outbreak in Culloden Point.
Testing is a routine and crucial step in monitoring the health of farmed fish stocks. Outbreaks are fairly rare but do happen on occasion. This past May, the virus was detected at a Mainstream Canada facility in Dixon Bay north of Tofino, requiring the culling of over 560,000 fish from that farm to prevent further spread. Another outbreak took place in the same area at the end of July and also required the culling of fish.
Hawthorn stated such "health challenges are an infrequent but normal part of farming natural food."
IHN virus has no impact on human health. Pacific salmon are carriers of the virus, and while it does not typically make them sick, Atlantic salmon are not immune. The incurable virus has the ability to be transferred between fresh and saltwater fish and can persist in the water for a prolonged period of time. A commercial vaccine is available, but treatment is typically impractical given its expense.
All fish were removed by closed containment on Aug. 9 and are being rendered by an approved contractor in a manner that destroys the virus, said Hawthorn.
"While almost all the fish at this farm were in good health, we know that fish at farms with any confirmed incidence of IHN virus have a poor prognosis,"added Hawthorn. "The right and responsible response was to quickly and humanely remove the fish before their health might be compromised and, of course, to prevent the virus from spreading to other farms."
