Fish Ulcers


Commonly Infected Wildlife

Numerous species of fish can be affected.

Is This Animal Infected?

Typically open wounds in the skin and flesh.
Seriously affected fish may be pop-eyed and have a fluid-filled gut (dropsy).

Can I Get It?

Human infection is possible, but rare. Some bacteria can infect human skin through open wounds.

How Bad Can It Get?

Humans are typically not susceptible to the bacteria that cause fish ulcers, but some skin infections may require antibiotic treatment.

Symptoms in Humans

Red and/or swollen areas surrounding cuts or wounds from handling infected fish.

Ulcers on the skin of a fish
Fish ulcers
John Plumb, Auburn University
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Protect Myself and Others

  • All fish with ulcers should be handled with care, preferably while gloved. Avoid getting spined when handling.
  • Superficial ulcers can be cut out of the fillet, but fish with pop-eye or dropsy should not be eaten.
  • Consume fish fillets like any other, by properly cleaning, preparing, and cooking the fish to 145°F.

Safe for Pets?

Yes. There is no known health risk when fish are properly cooked.

What Causes It?

In freshwater game fish, the most common causes are three bacteria in the genus Aeromonas; in striped bass and hybrid striped bass, Mycobacterium ulcerans and M. marinum; and in channel catfish, Edwardsiella spp.