Lung infections are classified by anatomic site along the respiratory tract: upper respiratory tract infections (nose, pharynx, larynx) versus lower respiratory tract infections (trachea, bronchi, alveoli), with the latter further divided into tracheobronchitis and the more serious alveolar infection, pneumonia. This site-based classification determines etiology (viral versus bacterial), severity, and clinical significance, since infections tend to spread contiguously along the tract rather than remaining isolated to one structure. This is a topic in respiratory medicine concerned with the taxonomy and epidemiology of infectious lung disease.
Lung infections are classified by anatomic site along the respiratory tract: upper respiratory tract infections (nose, pharynx, larynx) versus lower respiratory tract infections (trachea, bronchi, al…