Bronchitis and bronchiolitis are easy to confuse because they sound so similar. However, this similarity is not because of any link between the conditions themselves, but rather because they affect similarly named structures in the lungs. If your respiratory consultant tells you that your child has bronchitis, it means something very different to bronchiolitis.
Bronchitis isn’t a specific condition. Rather it is a symptom that affects a part of your lungs called the bronchi. The bronchi are the two main airways that branch off your windpipe into your lungs. They are responsible for producing mucus that traps dust and dirt to prevent it from going further in. Some respiratory conditions and infections can cause the bronchi to become inflamed and to increase their mucus production. The excess mucus will cause you to cough. This persistent, wet cough is what your respiratory consultant means by bronchitis. It can happen in both adults and children, and it can have various causes, including exposure to smoke and bacterial or viral infections.
Bronchiolitis is a kind of lung infection that affects the smaller airways that branch off the bronchi. When these narrow airways, known as bronchioles, become inflamed due to an infection, it can become much harder for air to get into your lungs. The infection is most often caused by the Respiratory Syncytial Virus, but other viruses such as the adenovirus and rhinovirus can cause bronchiolitis too. Unlike bronchitis, bronchiolitis only affects children. It is most common in babies who are less than one year old. In most cases, the symptoms are no worse than a common cold, but there is a risk that bronchiolitis could cause serious breathing difficulties that require hospital treatment by a respiratory consultant. Babies who were born prematurely or who have a heart or lung condition are at greatest risk, but you should always seek help if your child is having trouble breathing.