1976 Philadelphia Legionnaires' disease outbreak failed. The disease was finally produced in guinea pigs. The CDC announced the discovery at a press conference on January 18, 1977. The bacterium was later named "Legionella pneumophila". "Legionella pneumophila" is the most common cause, but sometimes other species of Legionella bacteria also cause Legionnaires' disease. The terms "Philadelphia fever" and "Legion fever" appear to have been used at the time of the outbreak and for shortly thereafter, although at least one 2008 source which covers disease in a historical narrative sense also included "Legion Fever" as alternate name. Both the World Health Organization in 2018 and the United
Pneumonia on the symptoms and physical examination. Chest X-ray, blood tests, and culture of the sputum may help confirm the diagnosis. The disease may be classified by where it was acquired with community, hospital, or health care associated pneumonia. Vaccines to prevent certain types of pneumonia are available. Other methods of prevention include handwashing and not smoking. Treatment depends on the underlying cause. Pneumonia believed to be due to bacteria is treated with antibiotics. If the pneumonia is severe, the affected person is generally hospitalized. Oxygen therapy may be used if oxygen levels are low. Pneumonia affects approximately 450 million people