What is bronchiolitis?

Bronchiolitis is an infection of the lower respiratory tract. It most often occurs in infants under age 1. It is the number one cause of hospitalization in infants.


Symptoms of bronchiolitis include:

  • runny nose
  • congestion
  • fever
  • cough
  • changes in breathing
  • decreased appetite
  • irritability
  • vomiting


Bronchiolitis is usually diagnosed based on a physical examination and medical history. In some cases, your child’s doctor may order an x-ray or blood tests to help confirm the diagnosis.


In most cases, bronchiolitis is mild and can be treated at home. If your child is having trouble breathing, he or she may need treatment in the hospital.

Learn more about Pediatric Pulmonology, Allergy, Immunology and Sleep services at Boston Children’s Health Physicians.