<s>[INST] What is pneumonia? [/INST] It’s an infection that is triggered when germs enter the lungs. When this happens the body’s immune system is triggered to fight the infection and it does this by inflaming the lung’s air sacs (alveoli). When these air sacs start to fill up with liquid and pus as part of the process of fighting the infection, the symptoms of pneumonia start to appear. Source: Harley Street ENT Clinic. Link: https://www.harleystreetent.com/blog/all-you-need-to-know-about-pneumonia. Field: Lung Disease. Disease: Pneumonia </s>