Legionnaires' disease (MONDO_0005824) is a pneumonia caused by Legionella pneumophila and other Legionella species, which is characterized by fever, cough, progressive respiratory distress, and which is often accompanied by extrapulmonary manifestations. Also known as: Legionella, Legionella pneumonia, Legionnaires' Disease, infection by Legionella pneumophilia, legionnaire's disease.