The Food Safety Authority (FSA) performed audits at all sites that reported escapees after the storm and tests found PD in some escaped fish.
"There are serious concerns with large quantities of fish on the run," said Hallgeir Herikstad, regional director of Region South and West, FSA.
"PD has already been detected in this area, and the infection pressure is clearly worse - for both aquaculture and wild fish - when escaped fish swim around freely."
Herikstad said it was no surprise that PD was found in escaped fish. "In the area where escapes have occurred and where escapees are caught, PD is very widespread. The disease is established here, and annual reports show many PD cases. It is therefore not applicable to the FSA to ask Fisheries assistance to trace the fish now."
"We are not sure what consequences sick escapees have on wild fish stocks as we know too little about transmission to wild fish."