Legionnaire disease was first described in 1976 after an outbreak of fatal pneumonia at a Legionnaires convention. The newly described organism which caused the disease was named Legionella pneumophila, shown in this picture. (Image courtesy of the Centers for Disease Control and Prevention.)
Review Date 1/15/2019
Updated by: Denis Hadjiliadis, MD, MHS, Paul F. Harron Jr. Associate Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.