Wheezing in infants

Wheezing in infants: What whistling sounds during breathing mean

Whistling sounds or wheezing on exhalation (wheezing) — this is a symptom that always indicates narrowing of the lower airways (bronchi or bronchioles). It is not a disease in itself, but a sign that can accompany various illnesses. The appearance of wheezing in an infant is always a serious reason to seek medical attention immediately.

Why does wheezing occur?

The whistling sound occurs when air forcefully passes through narrowed airways, just as air whistles when passing through a narrow slit. In infants the airways are already very narrow, so even a slight swelling or spasm can lead to significant narrowing.

Most common causes of wheezing in infants:

• Bronchiolitis. This is the most common cause in children under one year. It is a viral infection (most often caused by RSV) that affects the smallest bronchi — the bronchioles. Inflammation and swelling of the mucous membrane lead to wheezing, cough and shortness of breath.
• Virus‑induced wheezing. Some viral infections can cause a temporary bronchial spasm in susceptible children, even without causing classic bronchiolitis.
• Asthma. Although the diagnosis “bronchial asthma” is rarely made in children under 2‑3 years, recurrent episodes of wheezing can be its first manifestation, especially with a strong family history. Read more here: “Asthma symptoms”.
• Foreign body aspiration. When a child inhales something that becomes lodged in the airways.
• Gastro‑esophageal reflux (GERD). With severe reflux stomach contents can enter the airways, causing inflammation and wheezing.

Parental actions

The appearance of wheezing, especially if accompanied by signs of respiratory distress (rapid breathing, retractions of the soft areas of the chest), is an indication for an emergency call to ambulance services. Do not try to treat this on your own. A doctor should examine the child, listen to the lungs and determine the cause in order to prescribe appropriate treatment.