Health officials said a man who died was in his 40s and was from the Gorgie neighborhood in western Edinburgh, The Scotsman reported. Gorgie has been the center of the outbreak. The first man to die was a construction worker in the neighborhood.
Six buildings were being investigated as possible sources of the disease.
The number of confirmed and suspected cases of the respiratory infection reached 89 Thursday, with one new suspected case being reported.
Nicola Sturgeon, the Scottish health secretary, said epidemiologists believe the outbreak has peaked. Health officials said the second casualty was one of the first patients to be treated for the disease and had significant medical problems before he became sick.
Legionnaires' disease was first identified in early 1977, several months after men attending an American Legion convention at a Philadelphia hotel were sickened with a pneumonia-like disease. The cause is a bacterium that lives in warm water and outbreaks have been caused by contaminated water in air-conditioning systems and hot tubs.