Signs of Disease

In individual fish:

  • Internal hemorrhages
  • External hemorrhages
  • Ascites (fluid in the abdomen)
  • Exophthalmia (bulging eyes)
  • Erratic swimming

In populations of fish:

  • Rapid die offs

Some fish species may be infected without showing signs of disease. These fish can spread the virus to other fish or locations and contaminate water sources or equipment.

Clinical Signs of VHS in Fish. Photo courtesy of Paul Bowser, Aquatic Animal Health Program, College of Veterinary Medicine, Cornell University
Clinical Signs of VHS in Fish. Photo courtesy of Paul Bowser, Aquatic Animal Health Program, College of Veterinary Medicine, Cornell University
Clinical Signs of VHS in Fish. Photo courtesy of Paul Bowser, Aquatic Animal Health Program, College of Veterinary Medicine, Cornell University
Hemorrhages in internal organs. Photo courtesy of Paul Bowser, Aquatic Animal Health Program, College of Veterinary Medicine, Cornell University
Clinical Signs of VHS in Fish. Photo courtesy of Paul Bowser, Aquatic Animal Health Program, College of Veterinary Medicine, Cornell University
Bulging eyes. Photo courtesy of Dr. Mohamed Faisal, Michigan State University