Bronchiolitis is a viral disease of the lungs most common in young children. The virus causes swelling airways in the small airways of the lungs, called bronchioles, and a buildup of mucus in the airways. This can make breathing more difficult and lead to coughing and wheezing.
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Bronchiolitis is caused by one of several different types of viruses. These viruses are easily spread from person to person like a common cold. It is passed most easily through droplets of moisture that are released into the air with coughs or sneezing. These droplets may be inhaled by others or land on common surfaces like counters and doorknobs. A healthy person can pick up the virus by inhaling it in the air or coming in contact with the virus on surfaces then touching their face.

Risk Factors

Bronchiolitis can affect anyone, but is most common in children under the age of 2 years old. It is also most common during the winter season.
Factors that may increase a child's risk include:
Factors that increase a child's risk of bronchiolitis include:


At first bronchiolitis will have the same symptoms as a common cold. This may include stuffy or runny nose, cough, and mild fever. After a few days, the cough will worsen and breathing rate will increase.
Symptoms may include:


You will be asked about your child's symptoms and medical history. A physical exam will be done. The doctor will most likely be able to diagnose bronchiolitis based on the history and physical exam.
Lab tests of the blood or mucus or chest x-ray may be done if there is a concern about a secondary infection.
The doctor may also assess the risk of a severe infection based on health history.


Viral infections cannot be cured with medication. The virus needs to run its course. Bronchiolitis will usually clear completely on its own by 2-3 weeks.
Treatment will help manage symptoms during more intense periods of the infection.
Management of less severe symptoms includes:
If breathing becomes difficult, hospitalization may be needed. Care may include:


There is no vaccine to prevent bronchiolitis itself. There are some medications that may lessen the risk of bronchiolitis by respiratory syncytial virus (RSV):
To help decrease the risk of bronchiolitis or any respiratory infection:


Family Doctor—American Academy of Family Physicians

Kids Health—Nemours Foundation


The Canadian Lung Association

Caring for Kids—The Canadian Paediatric Society


Bronchiolitis. Healthy Children—American Academy of Pediatrics website. Available at: Updated August 20, 2015. Accessed September 15, 2015.

Bronchiolitis. EBSCO DynaMed website. Available at: Updated September 14, 2015. Accessed September 15, 2015.

Ralston S, et al. Clinical Practice Guideline: Diagnosis, Management and Prevention of Bronchiolitis. Pediatrics Vol. 134 No. 5 November 1, 2014 pp. e1474 -e1502. Available at: Accessed September 15, 2015.

Treating bronchiolitis in infants. Healthy Children—American Academy of Pediatrics website. Available at: Updated July 28, 2014. Accessed January 15, 2015.

Working Group of the Clinical Practice Guideline on Acute Bronchiolitis, Fundació Sant Joan de Déu. Clinical practice guideline on acute bronchiolitis. Barcelona (Spain): Catalan Agency for Health Technology Assessment and Research (CAHTA); 2010.

2/5/2009 DynaMed's Systematic Literature Surveillance Panickar J, Lakhanpaul M, Lambert PC, et al. Oral prednisolone for preschool children with acute virus-induced wheezing. N Engl J Med. 2009;360:329-338.

6/8/2015 DynaMed's Systematic Literature Surveillance National Institute for Health and Care Excellence. Bronchiolitis in children. Available at: Published May 2015. Accessed June 8, 2015.

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