what is pneumonia
Pneumonia (nu-MO-ne-ah) is an infection in one or both of the lungs. Many germsâsuch as bacteria, viruses, and fungiâcan cause pneumonia.The infection inflames your lungs' air sacs, which are called alveoli (al-VEE-uhl-eye).neumonia (nu-MO-ne-ah) is an infection in one or both of the lungs. Many germsâsuch as bacteria, viruses, and fungiâcan cause pneumonia.