Is pneumonia dangerous?

My 70-year-old uncle has pneumonia. Kindly let me know how bad his condition is.

Boulos (by SMS)

Pneumonia is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus (purulent material), causing cough with phlegm or pus, fever, chills, and difficulty breathing. A variety of organisms, including bacteria, viruses and fungi, can cause pneumonia. Depending on how severe the pneumonia is, interference with lung function can be very dangerous. No oxygen, no life. In fact, at his age pneumonia can be much more deadly for your uncle than in a younger person. It also depends on which pathogen or pathogens are involved. Some are deadlier than others.

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