What Is Pneumonia?

Pneumonia (nu-MO-ne-ah) is an infection in one or both of the lungs. Many small germs, such as bacteria, viruses, and fungi, can cause pneumonia.

The infection causes your lungs’ air sacs, called alveoli (al-VEE-uhl-eye), to become inflamed. The air sacs may fill up with fluid or pus, causing symptoms such as a cough (with phlegm), fever, chills, and trouble breathing.

Overview

Pneumonia and its symptoms can vary from mild to severe. Many factors affect how serious pneumonia is, such as the type of germ causing the infection and your age and overall health.

Pneumonia tends to be more serious for:

• Infants and young children.
• Older adults (people 65 years or older).
• People who have other health problems like heart failure, diabetes, or COPD (chronic obstructive pulmonary disease).
• People who have weak immune systems as a result of diseases or other factors. These may include HIV/AIDS, chemotherapy (a treatment for cancer), or an organ or bone marrow transplant.

Outlook

Pneumonia is common in the United States. Treatment for pneumonia depends on its cause, how severe your symptoms are, and your age and overall health. Many people can be treated at home, often with oral antibiotics.

Children usually start to feel better in 1 to 2 days. For adults, it usually takes 2 to 3 days. Anyone whose symptoms get worse should be checked by a doctor.

People who have more severe symptoms or underlying health problems may need treatment in a hospital. It may take 3 weeks or more before they can go back to their normal routines.

Fatigue (tiredness) from pneumonia can last for a month or more.

August 2008