What is Pneumonia? What are the 4 Stages of Pneumonia?
Pneumonia is an infection of one or both of the lungs. It causes the air sacs of the lungs to fill up with fluids and/or pus, or purulent material. Affected persons have varying degrees of cough, fever, and shortness of breath or trouble breathing. Pneumonia can be caused by a variety of organisms such as fungi, viruses, and bacteria. Pneumonia progresses through various stages as the condition worsens. What are the 4 stages of pneumonia? Read on to find out.