US Fish & Wildlife Service


Date of this Version



Published by UNITED STATES DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Division of Fishery Ecology Research Washington, D. C. 20240


Aeromonas salmonicida is a gram-negative bacterium that usually produces a water-soluble brown pigment. It was first described by Emmerich and Weibel (1890) as the cause of salmonid furunculosis in Germany. Although the disease was first considered to be limited to salmonids, studies by the Furunculosis Committee (Mackie et al. 1930, 1933, 1935) showed that A. salmonicida also infected other fish species. Present indications are that A. salmonicida or its variants also produce other diseases, such as ulcerative disease of goldfish (Carassius auratus), erythrodermatitis of common carp (Cyprinus carpio), ulcer disease of trout, and systemic infections among several warmwater and marine species.