Pneumonia
When bacteria, viruses, fungi or parasites enter the lungs causing an infection, this is known as Pneumonia. Though Pneumonia can affect anyone at any age, it's more common in the elderly (above 65 years old), young children and those with compromised immune systems. Pneumonia tends to obstruct the efficient exchange of air within the lungs, leading to lower levels of oxygen in the blood as well as the impaired removal of carbon dioxide from the body. The severity of Pneumonia ranges from mild to life threatening and depends on various factors.