What is double pneumonia and how does it affect the lungs?

Double pneumonia (also referred to as bilateral pneumonia) is an infection that affects both lungs simultaneously. The condition causes inflammation of the air sacs in the lungs, called alveoli, which then fill with fluid or pus. This inflammation significantly complicates recovery, especially for elderly patients like 88-year-old Pope Francis who has been hospitalized with this condition. The fluid buildup in both lungs makes breathing difficult and reduces the lungs' ability to properly exchange oxygen. For an elderly person like Pope Francis, this bilateral infection presents more serious health challenges than single-lung pneumonia, requiring more intensive medical treatment and careful monitoring during recovery.