BRANFORD, Conn.--(BUSINESS WIRE)--A study published online in the journal PLoS One (1) sheds new light onto the mysterious disease which has cause widespread damage to farmed salmon populations in Norway and the United Kingdom. Heart and skeletal muscle inflammation (HSMI), an often fatal disease, was first detected in salmon on a farm in Norway in 1999, and has now been reported in 417 fish farms in Norway and in the UK. The disease destroys heart and muscle tissue and kills up to 20 percent of infected fish. Although studies have indicated an infectious basis, recent efforts to identify the pathogen causing the disease have been unsuccessful.