Amoebic gill disease (AGD) is a potentially fatal disease of some marine fish. It is caused by Neoparamoeba perurans, the most important amoeba in cultured fish. It primarily affects farm-raised fish of the family Salmonidae, most notably affecting the Tasmanian Atlantic salmon (Salmo salar) industry, costing the A$20 million a year in treatments and lost productivity.[1] Turbot, bass, bream, sea urchins and crabs have also been infected.
The disease has also been reported affecting the commercial salmon fisheries of the United States, Australia, New Zealand, France, Spain, Ireland and Chile.[2] It was first diagnosed in the summer of 1984/1985 in populations of Atlantic salmon off the east coast of Tasmania and was found to be caused by N. perurans n.sp.[3]