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Pneumonia can be very serious, even deadly. To protect yourself, reduce your risks and respond quickly to symptoms.
6. Where can I go to learn more?
Answers
Pneumonia is an infection or inflammation in the lungs. It may be caused by infection with bacteria, viruses, mycoplasma (tiny organisms with traits of both bacteria and viruses) or fungi. Inhaling food, liquid, gases or dust can also cause pneumonia, as can diseases, such as tuberculosis.
Pneumonia clogs the air sacs in the lungs with pus and other liquid. The air sacs usually collect oxygen from the air we breathe in and pass it on to the bloodstream. When this fluid clogs the air sacs, the lungs can't collect oxygen effectively.
Pneumonia can range from mild to severe, depending on the cause and the general health of the person.
The symptoms of pneumonia may include chills; severe chest pain; a cough that produces greenish or yellow mucus, or even bloody mucus; fever; bluish lips or nail beds; muscle pain; weakness; breathlessness; and nausea or vomiting.
The exact combination of symptoms depends on the cause of the pneumonia.
Those at high risk for pneumonia include:
- People with lung diseases.
- People being hospitalized, especially if using a ventilator to breathe.
- People with viral infections, such as the flu.
- People with chronic diseases, such as congestive heart failure, diabetes or sickle cell anemia.
- People with weakened immune systems.
- Babies 2 years old or younger and adults 65 or older.
Antibiotics may help treat pneumonia caused by bacteria. Antibiotics can also help with pneumonia caused by mycoplasma or by inhaling food or liquid.
Pneumonia caused by a virus tends to be mild and usually heals on its own, though antiviral medication may be used in some cases. When a fungus causes pneumonia, antifungal medication may be used.
Oxygen, medicine to relieve chest pain, and medicine to relieve a violent cough are used as needed.
A healthy young person may recover from pneumonia in as little as a week. For older people it may take several weeks.
To reduce your risk of pneumonia:
- Stay healthy. Good health increases resistance to all respiratory infections.
- Get a flu shot. This helps prevent influenza, which can lead to pneumonia.
- If you're at high risk for pneumonia, get a pneumococcal vaccine. Two types of vaccine are available. They help prevent the most common types of bacterial pneumonia.
6. Where can I go to learn more?
To learn more about pneumonia, visit the Pneumonia health topic center. You can also find out more at these websites:
Reviewed 5/15/2025