Bronchiolitis

Bronchiolitis is a common lung infection that affects the small airways of the lungs, called bronchioles. It occurs most often in infants and young children, especially under the age of two. The condition is usually caused by a viral infection and leads to inflammation and mucus buildup in the airways, making breathing difficult. Bronchiolitis is typically mild and improves with supportive care, but some cases can become serious and require medical attention.

Symptoms

Symptoms of bronchiolitis often begin like a common cold and may worsen over several days. Common symptoms include:

• Runny nose and nasal congestion

• Mild cough that may become persistent

• Fever, usually low-grade

• Wheezing or whistling sounds while breathing

• Rapid or labored breathing

• Difficulty feeding in infants due to breathing trouble

In severe cases, symptoms may include pauses in breathing, bluish skin color, or extreme fatigue.

Causes

Bronchiolitis is most commonly caused by viral infections that spread easily from person to person. Common causes include:

• Respiratory syncytial virus, the most frequent cause

• Other respiratory viruses such as rhinovirus, influenza, or parainfluenza

• Exposure to infected respiratory droplets from coughing or sneezing

• Touching contaminated surfaces and then touching the face

The infection causes swelling and mucus production in the small airways, leading to airflow obstruction.

Risk factors

Certain factors increase the risk of developing bronchiolitis or having more severe symptoms:

• Age under two years, especially infants younger than six months

• Premature birth

• Weakened immune system

• Chronic lung disease or congenital heart disease

• Exposure to tobacco smoke

• Crowded living conditions or daycare attendance

Complications

Most children recover fully from bronchiolitis, but complications can occur, particularly in high-risk infants:

• Dehydration due to poor feeding

• Low oxygen levels in the blood

• Breathing difficulties requiring hospitalization

• Increased risk of recurrent wheezing later in childhood

• Secondary bacterial infections in rare cases

Prompt medical care can help reduce the risk of serious complications.

Prevention

While bronchiolitis cannot always be prevented, certain measures can reduce the risk of infection:

• Frequent handwashing to limit virus spread

• Keeping infants away from people with cold-like symptoms

• Cleaning and disinfecting commonly touched surfaces

• Avoiding exposure to tobacco smoke

• Breastfeeding to support the infant’s immune system

Early recognition of symptoms and supportive care are key to managing bronchiolitis and promoting recovery.