Legionnaires' disease on symptom onset dates from past outbreaks. In this way, the eventual likely size of an outbreak can be predicted, enabling efficient and effective use of public health resources in managing an outbreak. The first recognized cases of Legionnaires' disease occurred in 1976 in Philadelphia; among more than 2000 attendees of an American Legion convention held at the Bellevue-Stratford Hotel, 182 attendees contracted the disease and 29 of them died. In April 1985, 175 people in Stafford, England, were admitted to the District or Kingsmead Stafford Hospitals with chest infection or pneumonia. A total of 28 people died. Medical diagnosis
Classification of pneumonia now the most commonly used classification scheme, attempts to identify a person's risk factors when he or she first comes to medical attention. The advantage of this classification scheme over previous systems is that it can help guide the selection of appropriate initial treatments even before the microbiologic cause of the pneumonia is known. There are two broad categories of pneumonia in this scheme: community-acquired pneumonia and hospital-acquired pneumonia. A recently introduced type of healthcare-associated pneumonia (in patients living outside the hospital who have recently been in close contact with the health care system) lies between these two categories. Classification