What Causes Respiratory Tract Infection?

Respiratory tract infections are the most common cause of short-term disability in the United States. Most of these infections such as common cold, pharyngitis (sore throat), and laryngitis which involves the upper airways.

For pharyngitis, viral upper respiratory tract infection that produces postnasal drip, such as the common cold, and seasonal allergies are the most common causes of sore throat.

Organisms such as Streptococcus, Mycoplasma pneumoniae, Chlamydia pneumoniae, and Neisseria gonorrhoeae cause bacterial pharyngitis.

Laryngitis can be caused by cold or flu, acid reflux, overuse of voice and irritation, such as from allergies or smoke.

Infections of the lower respiratory tract occur most frequently in the young, the very old, or individuals with impaired immunity or underlying disease. In all cases, the body’s normal defense mechanisms are impaired.

Here are some of the common lower respiratory diseases and their causes:

Pneumonia is caused by various organisms such as D. pneumoniae, S.aureus, E.coli. Hinfluenzae

Tuberculosis is a bacterial infectious disease caused by Mycobacterium tuberculosis and spread via airborne droplets when infected persons cough, sneeze, or laugh.

Acute bronchitis and Emphysema is caused by cigarette smoking, infection, inhaled irritants, heredity, allergic factors, and aging

Lung Cancer are caused by inhaled carcinogens, primarily cigarette smoke but also asbestos, nickel, iron oxides, air silicone pollution, preexisting pulmonary disorders (TB, COPD).

source: mdinfo