In total, 12 cases were found in a wild juvenile Atlantic salmon population and 30 fish have been destroyed.
Treatment of infected fish is being considered.
Gyrodactylus salarisble first demonstrated in Rana river in 1975, then the parasite spread to Bjerke (1980), Røssåga (1980), Bardalselva (1989), Sanna River (1989) and Slettelva (1993)