Bronchiolitis is a common lung infection in young children and infants. It causes congestion in the small airways (bronchioles) of the lung. Bronchiolitis is almost always caused by a virus. Typically, the peak time for bronchiolitis is during the winter months.

Bronchiolitis starts out with symptoms similar to those of a common cold but then progresses to coughing, wheezing and sometimes difficulty breathing. Symptoms of bronchiolitis can last for several days to weeks, even a month.

Most children get better with supportive care at home. A very small percentage of children require hospitalization.

Symptoms Causes Risk factors Complications Prevention

For the first few days, the signs and symptoms of bronchiolitis are similar to those of a common cold:

  • Runny nose
  • Stuffy nose
  • Cough
  • Slight fever (not always present)

After this, there may be a week or more of breathing difficulty or a whistling noise when breathing out (wheezing).

Many infants will also have an ear infection (otitis media).

When to see a doctor

If it's difficult to get your child to eat and his or her breathing becomes more rapid or labored, contact your child's doctor. This is especially true if your child is younger than 12 weeks old or has other risk factors for bronchiolitis — including premature birth or a heart or lung condition.

The following signs and symptoms are reasons to seek prompt medical attention:

  • Vomiting
  • Breathing very fast — more than 60 breaths a minute — and shallowly
  • Skin turning blue, especially the lips and fingernails (cyanosis)
  • Lethargy
  • Refusal to drink enough fluids, or breathing too fast to eat or drink
  • Audible wheezing sounds
  • Ribs seem to suck inward when infant inhales

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