Bronchiolitis Dr Trisha Macnair Bronchiolitis is a common serious respiratory infection among babies. It causes inflammation of the bronchioles - the smallest airways in the lungs.

In this article

What causes it? Who's affected?

What are the symptoms? What's the treatment?

Bronchiolitis is caused by a virus - in the majority of cases one called the respiratory syncytial virus (RSV).

Of those affected, 90 per cent are under nine months of age. Bronchiolitis is uncommon in children over 12 months.

It usually occurs in winter. Premature babies with lung disease or babies with congenital heart disease are most at risk.

Initial symptoms may resemble a cold, with snuffly nose, mild fever, irritability and loss of interest in feeds.

After a couple of days, a dry 'rasping' cough and increasing breathlessness may develop.

The baby may be wheezy and seem to have trouble breathing, taking frequent shallow breaths and drawing in the chest wall below and between the ribs. These breathing problems may interfere with feeds.

More worrying are episodes where the baby stops breathing for more than ten seconds at a time, known as recurrent apnoea. The baby may become drowsy and develop a blue tinge to their lips.

If your baby has the above symptoms, call your doctor or NHS Direct on 0845 4647, or 08454 242424 if you're in Scotland. Call an ambulance if your child is not breathing properly, is blue or is very drowsy.

The diagnosis is made on the basis of symptoms and physical examination.

Mild bronchiolitis can be managed at home with a combination of paracetamol syrup for fever and discomfort, and plenty of fluids to avoid dehydration.

Antibiotics are of no benefit but your doctor may recommend a bronchodilator drug to help breathing.

Babies with more severe bronchiolitis need to be treated in hospital where they may be given humidified oxygen through tubes into the nose or a headbox or, in very severe cases, artificial ventilation (about one in 50 babies needs this).

Antiviral drugs may be used, especially in children at high risk, and intravenous fluids may be needed.

Most children recover within two weeks, although up to 50 per cent have a recurrent cough and wheeze for several years. There is rarely permanent damage to the airways.

Monthly antibody injections against RSV are sometimes offered for babies at high risk.

This article was last medically reviewed by Dr Rob Hicks in November 2007