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Pneumonia is an infection of the lungs that can cause mild to severe illness in people of all ages. Depending on the cause, it can often be treated with medicine or prevented with vaccines. However, it is still the leading infectious cause of death in children younger than 5 years old worldwide. Common signs of pneumonia include cough, fever, and difficulty breathing. You can help prevent pneumonia and other respiratory infections by following good hygiene practices, such as washing your hands regularly and disinfecting frequently touched surfaces, taking good care of your medical problems, and quitting smoking.

Common Causes of Pneumonia

Pneumonia can be caused by viruses, bacteria, and fungi. In the United States, common causes of viral pneumonia are influenza and respiratory syncytial virus (RSV), and a common cause of bacterial pneumonia is Streptococcus pneumoniae (pneumococcus). Pneumonia can also be caused as a result of being on a ventilator, known as ventilator-associated pneumonia.

Learn more below about the infections that commonly cause pneumonia.

Vaccines Can Help Prevent Pneumonia

In the United States, there are several vaccines that help protect against infections caused by bacteria or viruses that may cause pneumonia. These vaccines include


Lower Your Risk of Pneumonia

You are more likely to become ill with pneumonia if you smoke or have underlying medical conditions, such as diabetes or heart disease. However, you can lower your chances by taking good care of your medical problems, and quitting smoking.

Etiology of Pneumonia in the Community (EPIC) Study

The Etiology of Pneumonia in the Community (EPIC) study conducted by CDC, and three U.S. children’s hospitals,and five U.S. adult medical centers estimated the burden of community-acquired pneumonia hospitalizations among U.S. children and adults from January 2010 – June 2012.