Community-acquired pneumonia is a lung infection that develops in people outside of a hospital.
Many viruses, bacteria and fungi can cause pneumonia.
The most common symptom of pneumonia is a productive cough, but chest pain, chills, fever, and shortness of breath are also common symptoms.
The doctor diagnoses community-acquired pneumonia by auscultating the lungs with a stethoscope and reading an x-ray or computed tomography (CT) scan of the chest.
Antiviral or antifungal drugs are used, depending on which microorganism doctors suspect is causing the pneumonia.
In order to help guide acute community-acquired pneumonia in emergency departments, IDSA and ATS proposed in 2007 to define severe pneumonia by the presence of a major criterion (mechanical ventilation or vasopressors) or by the presence of 3 minor criteria from a list of 9 clinical-radiobiological signs. These criteria are confirmed by a study in 2009.