National Aquatic Animal Health Program - Fact Sheet

Viral Haemorrhagic Septicaemia (VHS) in various Great Lakes fish species 

There have been increasing reports of wild fish mortalities associated with the emergence of Viral Haemorrhagic Septicaemia (VHS) in various Great Lakes finfish species. Up until 2005, this infectious viral disease was believed to be naturally present in coastal Atlantic and Pacific marine finfish species in North America.  Its recent emergence in the Great Lakes has affected freshwater fish for the first time in both Canada and USA.  This disease has NO human health effects.

What fish are affected?

To date, freshwater drum; smallmouth bass; crappie; muskellunge and bluegill have been affected by this disease in Canada. In the United States the virus has been detected in round goby, muskellunge, gizzard shad, walleye, white bass, silver redhorse, northern pike, freshwater drum, yellow perch, smallmouth bass, and shorthead redhorse.

How can I recognize affected fish?

Keeping an eye out for any freshwater fish showing the following signs is very helpful:

  • bulging eyes
  • pale gills
  • signs of bleeding around the eyes, bases of the fins, sides and head
  • darkening overall colour
  • distended (fluid-filled) belly
  • corkscrew swimming behaviour 
Photograph courtesy of Dr. J. Lumsden, University of Guelph

Photograph courtesy of Dr. J. Lumsden, University of Guelph

What do I do if I suspect the disease is present in a fish I have grown or caught?

If you see these signs or find a fish-kill please report this immediately to your local fisheries authority. The quicker the authorities are alerted, the quicker they can organise collection of samples for analysis by qualified fish health laboratories.

Do not move or transfer any fish that show signs of being sick from one body of water to another.

Anyone wishing to move live fish from one part of the Great Lakes to another (especially from areas noted as being positive for VHS) should contact their local fisheries authority or Fisheries and Oceans Canada.

Is it safe to touch affected fish?

Yes. This disease does NOT affect human health.

Where has VHS been detected?

On the Canadian side: Lake Ontario and Lake St. Clair. The USA has reports from Lake Erie; Lake St. Clair and the St. Lawrence River.

Where can I get more information?

Fisheries and Oceans Canada - National Aquatic Animal Health Registry;
e-mail: NRFD@DFO-MPO.GC.CA

Canadian Food Inspection Agency - National Aquatic Animal Health Division;
http://www.inspection.gc.ca/english/anima/aqua/proge.shtml

Ontario Ministry of Natural Resources - Natural Resource Information Centre;
Peterborough t: 1-800-667-1940

2010