1976 Philadelphia Legionnaires' disease outbreak States Center for Disease Control and Prevention (CDC) in 2017 only use the term Legionnaires' disease to refer to the serious version with pneumonia. CDC investigators quickly discovered outbreaks of respiratory disease caused by "L. pneumophila" dating back to 1959. An outbreak of what was dubbed Pontiac fever occurred in a health department in Pontiac, Michigan in July 1967. No one died. Although caused by the same bacterium, Pontiac fever is a milder ailment than Legionnaires' disease. Pneumonia is absent in those with Pontiac fever. An outbreak of pneumonia in July–August, 1965, at St. Elizabeths Hospital in Washington, DC, which
Classification of pneumonia Classification of pneumonia Pneumonia can be classified in several ways, most commonly by where it was acquired (hospital versus community), but may also by the area of lung affected or by the causative organism. There is also a combined clinical classification, which combines factors such as age, risk factors for certain microorganisms, the presence of underlying lung disease or systemic disease, and whether the person has recently been hospitalized. Community-acquired pneumonia (CAP) is infectious pneumonia in a person who has not recently been hospitalized. CAP is the most common type of pneumonia. The most common causes of CAP vary depending