Bronchiolitis is inflammation of the small airways of the lung. It is a contagious viral infection, mostly affecting babies during the winter months. It affects nearly 30% of newborns of whom more than 50% are under 6 months and it accounts for half of paediatric admissions. The Respiratory Syncytial Virus (RSV) is the principal infectious agent of the bronchiolitis. It begins in general in mid October until the end of the winter. Its peak is in December.
This infection which affects the small bronchi lasts within 5 to 10 days.
60% of the babies affected of bronchiolitis are boys.


Bronchiolitis is defined as the inflammation of the bronchioles, the final branches of the bronchi. If the term "infant bronchiolitis" is often used, it is because the disease occurs almost exclusively in young patients less than 2 years of age. Bronchiolitis occurs primarily during the autumn and winter seasons and is caused by a virus, namely RSV (Respiratory Syncytial Virus). This disease is contagious and is transmitted via airways or by the hands, which is why outbreaks are common in nurseries. The disease generally runs its course within a few days, but some forms may require hospital care. In the case that this condition recurs - beyond three episodes-, it is called infantile asthma.


Symptoms can be mild in most cases peaking in severity 2 -3 days after starting and present with
  • a simple cold, runny nose, cough and mild fever

As the infection travels down to the smaller airways symptoms can be more severe -
  • Episodes of dry cough, fast breathing that gradually becomes worse.
  • The nostrils can flare and the child wheezes with rapid breathing as high as 60 - 80 breaths per minute
  • Babies can have difficulty feeding as it requires much more effort for them to breath.
  • The cough can last from 2 to 3 weeks
  • Young babies quickly become tired and exhausted

Faced with these symptoms, it is important to see your GP quickly to deal with any respiratory complications which may require a hospitalisation.

What to do when a baby has bronchiolitis

  • If you have any concerns see you GP
  • Look for signs of dehydration (dry mucous membranes, reduced urinary output)
  • Encourage feeds and drinks regularly
  • Monitor feeds making note of how much they've taken or how well they've fed.
  • Air the room
  • Do not smoke in the baby's presence and do not take them to smoky places
  • Use disposable handkerchiefs
  • Do not let your baby return to nursery until all the symptoms have disappeared.
  • Antibiotics are not prescribed because as they do not have any effect on viruses, only if a secondary infection such as an ear infection is suspected are they given.

Observe your baby for deterioration and worsening of symptoms looking out for rapid breathing, high temperature and poor feeding.


To diagnose infant bronchiolitis, the doctor will listen to your child's lungs. Listening to particular sounds and observing how the child breathes is sufficient to establish the diagnosis. A chest X-ray can sometimes be practiced, and the search for causative virus can be made, but is not of great interest.


Treatment will depend on the general condition and age of the child. If the infant is very young or it is determined that his condition may worsen, hospitalization may be prescribed. Alternatively, treatment can be initiated by the doctor and continued at home. The nose must be frequently wiped to improve breathing capacity, and a follow-up by a physiotherapist is sometimes considered to help the child get rid of secretions. In the hospital, oxygen can be provided, and close monitoring is necessary. The meals should be divided and the position of the child should be raised slightly with the help of a cushion under the mattress.

Respiratory physiotherapy

In severe hospitalized case respiratory physiotherapy is performed. Its aim is to evacuate bronchial secretions which the child cannot manage to cough up on his own.

In periods of epidemic bronchiolitis

  • Wash hands thoroughly before dealing with your baby
  • Do not kiss your baby if you have cold symptoms or a bronchitis.
  • Ask his family members to avoid contact such as kissing especially if they too have coughs and colds.
  • Do not smoke in his presence and do not take him along in smoky places

Do not take the baby to places where he is likely to be in contact with people affected by infectious diseases (public transport, supermarkets, shops.)

Bronchiolitis and asthma

If your child has 2 or 3 episodes of bronchiolitis before the age of two this may reveal underlying asthma, especially if the child is from a family of allergic people.
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