What causes pneumonia?

Pneumonia is usually caused by a bacterial infection (bacterial pneumonia) or a viral infection (viral pneumonia). Pneumonia caused by an infection (infectious pneumonia) usually spreads from person to person when someone with the disease coughs, talks or sneezes. This shoots contaminated droplets into the air where they can be breathed in by others.

Pneumonia can also be caused by:

  • Choking or aspiration of food or liquid into the lungs

  • Fungal infection

  • Inflammation of the lungs due to exposure to toxic gases or lung irritants

  • Near drowning

  • Trauma

  • Yeast infection

What are the risk factors for catching pneumonia?

Pneumonia can occur in any age group or population. A number of factors increase the risk of catching or developing pneumonia. Risk factors include:

  • Acute bronchitis

  • Being an infant, young child, or older adult

  • Being immobile or bedridden for a long period of time

  • Being too ill or weak to effectively cough up mucus from the respiratory tract

  • Chronic diseases, such as congestive heart failure, COPD, asthma, and lung cancer

  • Diseases that result in an impaired or weakened immune system, such as HIV/AIDS

  • Drugs that suppress the immune system, such as corticosteroids and chemotherapy

  • Inhaling toxic gases or other lung irritants, such as heavy smoke

  • Living in a long-term care facility

  • Near drowning

  • Not being vaccinated against pneumonia

  • Problems with chewing or swallowing and choking on foods or liquids

  • Smoking

  • Trauma, such as rib fractures or injuries that cause prolonged immobility

Reducing your risk of pneumonia

Not all people with risk factors will get pneumonia, but you can lower your risk of catching or spreading pneumonia by:

  • Avoiding contact with a person who has pneumonia, a cold, or the flu

  • Avoiding exposure to air pollutants, toxic gases, and lung irritants, such as heavy smoke

  • Avoiding long periods of immobility

  • Covering your mouth and nose with your elbow (not your hand) or a tissue when sneezing or coughing

  • Following your health care provider’s advice for exercise and deep breathing exercises, and following your treatment plan for chronic illnesses and injuries

  • Getting vaccinated for pneumonia as recommended by your health care provider

  • Not smoking

  • Washing hands frequently with soap and water for at least 15 seconds


What is pneumonia?

Pneumonia is a general term for a variety of diseases that cause an inflammation of the lungs. Pneumonia is most often caused by a bacterial infection (bacterial pneumonia) or a viral infection (viral pneumonia). Typical symptoms of pneumonia include fever, shortness of breath, and a wet cough that produces thic... Read more about pneumoniaintroduction


What are the symptoms of pneumonia?

The symptoms of pneumonia are caused by inflammation of the lungs due to infection or irritation. In response, the lungs produce excessive amounts of thick phlegm, which must be coughed up in order to keep the airways open for effective breathing.

The types and severity of symptoms of pneumonia vary depending on a variety of factors, such as a person’s age, general health, and med... Read more about pneumoniasymptoms


How is pneumonia treated?

The goals of pneumonia treatment include minimizing the risk of serious complications and controlling symptoms to allow you to rest and recover. Mild to moderate cases of pneumonia that occur in generally healthy adults may be treated at home. More severe cases of pneumonia or cases in infants, older adults, or people with chronic diseases often require hospitalization.

Treatment ... Read more about pneumoniatreatments

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Sep 20, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Lungs, Breathing and Respiration

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