As heard on Outdoor Journal Radio
Anglers in Gimli, Manitoba, have recently observed an increase in walleye displaying wart-like growths on their skin and fins. These growths are caused by two viruses: Dermal Sarcoma and Lymphocystis. While these lesions may appear concerning, experts assure that they are primarily cosmetic and do not pose significant health risks.
Dermal Sarcoma manifests as gray-white or pinkish tumors on the fish’s skin and fins. Infections occur throughout the year, with a higher incidence during the spring spawning season when walleye congregate closely, facilitating virus transmission. Lymphocystis presents as clusters of white or cream-colored warts, commonly seen on the skin and fins of adult fish. This virus spreads through physical contact or water transmission, with infections more prevalent during colder periods in late winter and early spring.
Despite their unsightly appearance, these diseases are not known to infect humans. According to the Minnesota Department of Natural Resources, infected fish are safe to eat if cooked thoroughly, as the viruses do not penetrate the meat. Proper cleaning, preparation, and cooking of the fish to an internal temperature of 145°F (63°C) are recommended to ensure safety.
Fishermen are advised to handle affected fish with care. While there is no practical method to control the spread of these viruses in wild populations, maintaining proper hygiene and disposing of fish entrails responsibly can help minimize potential transmission. As always, anglers should ensure fish are cooked properly before
For a visual understanding of these lesions, you can watch the following video:
