
Overview
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 2/5/2025
Updated by: Jatin M. Vyas, MD, PhD, Roy and Diana Vagelos Professor in Medicine, Columbia University Vagelos College of Physicians and Surgeons, Division of Infectious Diseases, Department of Medicine, New York, NY. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.