Pneumonia is an inflammatory lung disease caused by infectious organisms. The small air sacs in the lungs fill with mucus and pus. It is a common complication of any serious illness, which can be fatal. Bacterial Pneumonia is very contagious; it is usually caused by staph, strep, or pneumo-bacilli. Viral pneumonia is an acute systemic disease, caused by a variety of virulent viruses. Viral Pneumonia does not respond to antibiotics. A chest x-ray is required for diagnosis.
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