Clinical Manifestations
The onset may be acute or insidious, and symptoms vary from mild fever, slight cough, and malaise to high fever, severe cough, and fatigue. Early in the illness, the cough is likely to be unproductive or productive of small amounts of whitish sputum. Breath sounds may include a few wheezes or fine crackles. Radiography reveals diffuse or patchy infiltration with a peribronchial distribution.