Introduction

Bronchiolitis is a viral infection of the small airways (bronchioles) of the lungs. It mainly affects children younger than 2 years of age and is rare in adults. It causes these small airways to swell, making breathing harder for your child. Symptoms of the condition are similar to that of a common cold like a runny nose or a cough and wheezing. This infection is more likely to occur during the winter months. 

Bronchiolitis is the most common respiratory tract infection in children under the age of 2. It isn’t usually serious, but complications can arise. 

It is important to monitor your child and understand what is normal. If they develop breathing difficulties, it is crucial to seek medical help immediately.¹

Causes and risks

Bronchiolitis is caused by contagious viruses that spread through droplets of saliva or mucus which become airborne after a child has sneezed or coughed. These airborne droplets can spread from one child to another quickly and can also stick to surfaces or objects which are frequently touched.²

Here are a few examples of viruses that can cause bronchiolitis:

• Respiratory syncytial virus (RSV)
• Influenza
• Adenovirus 
• SARS-Cov-2
• Parainfluenza

Children are more at risk of developing bronchiolitis if they:²

• Have a compromised immune system
• Were born before 37 weeks
• Have a congenital (present at birth) lung or heart condition 
• Are regularly in settings like daycare

Signs and symptoms

Symptoms of bronchiolitis can be respiratory or non-respiratory. Respiratory symptoms are associated with rapid breathing and wheezing, and non-respiratory symptoms are associated with fatigue, dehydration etc. When a child is infected with bronchiolitis, the small airways in their lungs are infected with a virus. This causes the airways to swell and fill with mucus, which can make it difficult to breathe. 

Early symptoms of bronchiolitis are similar to common cold symptoms, such as:¹

• Slight fever
• Runny nose
• Cough
• Fatigue
• Rapid breathing
• Wheezing
• Flaring of the nostrils 

Symptoms are usually at their worst between days 3 and 5, and you may find that your child’s cough generally gets better within 3 weeks. 

Symptoms of severe bronchiolitis include:¹

• Blue/ grey/ pale skin tone on the lips/ fingers/ toes
• Dehydration – dry mouth, not urinating, not producing tears when crying
• Chest retracts during breathing
• Unable to feed – difficulty swallowing/ sucking

If you notice any of these severe symptoms in your child, you should seek medical help immediately. 

Diagnosis

Bronchiolitis is diagnosed through physical examination. A diagnosis can be made without special tests, just by checking the temperature, listening to the chest and asking about symptoms. The doctor will consider your child’s age, symptoms, breathing sounds and body temperature to determine if they have bronchiolitis. They may also check the oxygen levels in your child’s blood by using a pulse oximeter, which is placed on their finger or toe.³

Other tests include a nasal fluid culture, where a swab collects fluid from inside your child’s nose to detect a virus causing the infection. In serious cases, chest X-rays may be used.¹

Treatment and management

There are different approaches to treat and manage symptoms of bronchiolitis.^7,8 Usually, the infection clears up on its own in a couple of weeks, therefore home care is preferential. Things like keeping your child hydrated with plenty of fluids, using saline drops for blocked noses and giving children ibuprofen or paracetamol to help symptoms are all effective methods to treat and manage your child’s symptoms at home.

Another effective way to help your child if they have a blocked nose/ chesty cough is to set up a humidifier near them, which will help loosen their mucus and congestion.

Complications

Sometimes, complications can arise from bronchiolitis in premature infants and in children who have cardiac or pulmonary problems or are immunodeficient. This is why it is important to remain vigilant and catch the infection early if you suspect your child has it. Complications include asthma, respiratory failure and pneumonia.^4,5

The risk of respiratory failure in children with RSV bronchiolitis is low, however, a small number of affected infants will require assisted ventilation in intensive care units each year.⁶

Sleep apnoea is also another commonly known complication of bronchiolitis, though acute, can cause children to be more at risk for developing severe lower respiratory disease. 

Prevention

It is difficult to prevent bronchiolitis as the viruses causing the infection are common. However, there are ways to lower the chance of your child developing the condition, including:

• Washing hands regularly
• Clean frequently touched surfaces/ toys regularly 
• Avoiding others whilst they are sick
• Not sharing cutlery 

It is important not to smoke around your child also, as children who breathe in cigarette smoke have higher risks of developing bronchiolitis.³

If your child has bronchiolitis, it is important to keep them at home away from other children as the infection is contagious and could spread to others.

Outlook

Bronchiolitis infections clear up on their own most of the time. Your child may have symptoms for up to a week. During this time, they may find it harder to eat full meals and be more dehydrated, but home care will alleviate these symptoms. 

If your child’s symptoms do not improve after a week or you find they are having difficulty breathing, you should seek immediate medical help. 

Some children who had bronchiolitis when they were younger may develop asthma. Some children may also develop pneumonia after having bronchiolitis, but this is much less common.¹ 

FAQs 

Are bronchiolitis and bronchitis the same thing? 

No, they are two different infections. Bronchiolitis affects the smaller airways (bronchioles) of the lungs, whereas bronchitis affects the large airways (bronchi). Also, bronchiolitis mainly affects younger children and bronchitis affects older children and adults mainly. 

Is bronchiolitis contagious?

Yes, it is a contagious viral infection. The virus can be spread quickly through cough/ sneeze droplets in the air. This is why it is important to keep infected children away from others to stop the spread of the infection. 

Summary 

Overall, bronchiolitis is usually harmless. The symptoms of this condition are similar to the common cold and can be treated with care at home and over-the-counter painkillers like ibuprofen and paracetamol. Symptoms like coughing, fever, runny nose or fatigue are all likely to go away on their own within a couple of weeks. However, if you notice any severe symptoms such as blue lips and chest retracting when breathing, you should try to get medical help immediately. 

Bronchiolitis is straightforward to diagnose, with the use of physical exams like checking the body’s temperature and breathing sounds. Washing hands regularly, cleaning frequently touched surfaces and keeping your unwell child away from others are all effective in stopping the spread of this infection. It is important to understand the possible complications of bronchiolitis to ensure timely care, proper management and getting treated earlier.