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The Manual's Editorial Staff

Last full review/revision Jul 2021| Content last modified Jul 2021
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What is pneumonia?

Pneumonia is an infection deep in your lungs. The infection involves the small air sacs in your lungs (alveoli). Pneumonia is different from infection of the air passages (bronchi) in your lungs. Infection of the air passages is called bronchitis Acute Bronchitis Your bronchi are the tubes that carry air into your lungs. Bronchitis is when the bronchi become swollen and irritated. Acute bronchitis starts suddenly, usually over a few days. Acute bronchitis... read more .

Inside the Lungs and Airways

Inside the Lungs and Airways

With pneumonia:

Every year, about 60,000 people in the United States die from pneumonia.

What causes pneumonia?

Pneumonia can be caused by many different types of germs, including:

  • Viruses (most common)

  • Bacteria

Usually, the germs are passed from one person to another. If you touch something that has germs on it, the germs can get in your mouth, nose, or throat. Usually, your body fights off the germs. But sometimes the germs get in your lungs and cause an infection.

What are the risk factors for getting pneumonia?

What are the symptoms of pneumonia?

  • Feeling run down

  • Fever and chills (shivering so hard your teeth chatter)

  • A cough that may or may not bring up mucus

  • Trouble breathing (feeling like you can't get enough air in)

  • Pain in your chest

Symptoms may be a little different in people who are very old:

  • They may not have a fever

  • Older adults may be confused and may not think clearly

How can doctors tell if I have pneumonia?

To find out if you have pneumonia, your doctor will:

If you're sick enough with pneumonia to be admitted to the hospital, doctors usually do blood tests and send samples of your sputum (stuff you cough up) to the lab.

How do doctors treat pneumonia?

Doctors treat pneumonia with:

  • Antibiotics that work best for the type of germ that’s causing the problem (but not all germs that cause pneumonia can be killed by antibiotics)

  • Medicines to help with fever or pain

  • Sometimes extra fluids or oxygen

You may need a chest x-ray about 6 weeks after treatment to make sure the pneumonia is gone, especially if you smoke or are older.

Most people can stay home during treatment. Some people may stay in the hospital, including people who:

How can I keep from getting pneumonia?

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Separation Anxiety and Stranger Anxiety
An important part of normal development is an infant’s growing attachment to its parents. As this bond strengthens, the infant may express fear or anxiety when the parents leave. This “separation anxiety” typically begins at around 8 months of age and resolves at around 24 months of age. Which of the following is the normal and expected infant behavior in reaction to a parent leaving the room during the time period of separation anxiety?
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