Final answer:
Pneumonia is an infection where the alveoli in the lungs fill with fluid and pus, causing symptoms like cough, chest pain, and fever. It can be caused by bacterial, viral, or fungal infections and is treated based on its cause, such as with antibiotics for bacterial pneumonia.
Step-by-step explanation:
The infection in which the air sacs fill with pus and other liquid is pneumonia. Pneumonia is a respiratory condition characterized by inflammation in the alveoli, which are the tiny air sacs in the lungs. This ailment is typically caused by infections from bacteria, viruses, or fungi. The alveoli get filled with fluid and pus, which impedes the oxygen-carbon dioxide exchange process that normally occurs in the lungs. People with pneumonia may experience symptoms such as coughing, chest pain, fever, and shortness of breath. Treatment for pneumonia primarily depends on its cause; for instance, bacterial pneumonia is treated with antibiotics.