Q.Why is pneumonia considered a dangerous disease?

The respiratory system is affected by environmental, occupational, personal and social factors. Asthma narrows and inflames the bronchi/bronchioles, usually triggered by allergens (dust, drugs, pollen, certain foods), causing breathing difficulty. Emphysema is chronic breathlessness from the gradual breakdown of alveolar walls, reducing gas-exchange surface area, most often from long-term cigarette smoking. Bronchitis is inflammation of the bronchi, typically from pollution or smoking, with cough, breathlessness and sputum. Pneumonia is lung inflammation from bacterial or viral infection, filling the alveoli with fluid/white blood cells and reducing gas-exchange surface area, with symptoms including sputum, congestion, breathlessness and sore throat - and can turn dangerous quickly, especially in vulnerable people. Tuberculosis, caused by Mycobacterium tuberculosis, aff …