Bronchiolitis: what is it and how to identify the symptoms of the disease?

During the first years of a child’s life, any illness is a cause for concern for parents, especially those that affect the respiratory system, as they tend to cause a lot of crying and discomfort to the baby. Among them, childhood bronchiolitis is very common and should be known to parents. ¹

The infection affects the internal structures of the lungs, more specifically the bronchioles, the condition requires special attention due to the risk of severely obstructing the airways of children. ¹

As they are already naturally quite narrow, any inflammation can have a considerable impact on the body’s movements of inhaling and exhaling air. ¹

This is the theme of our post, in which we will explain what childhood bronchiolitis is, its main causes, symptoms and how to treat it correctly to ensure recovery and avoid risks to the child’s health. ¹

Read and find out more!

What is bronchiolitis?

Bronchiolitis is a viral infection that affects the bronchioles, small branches of the airways that are in the region of the lung bronchi. They are about half a millimeter in diameter and act by contracting and relaxing breathing. ¹

In this infection, the virus affects the tissue lining the bronchioles, causing local inflammation, impairing breathing and generating a series of symptoms. In addition to the obstruction related to mucosal swelling, the situation worsens as secretion may accumulate. ¹

 

Consequently, the baby may show signs of shortness of breath. The condition is often confused with asthma attacks, due to wheezing, shortness of breath and difficulty breathing. ¹

Although it can occur throughout childhood, childhood bronchiolitis occurs most frequently in babies up to two years of age. Furthermore, in the first six months of life, the probability of contracting this disease is even greater. ¹

Can bronchiolitis also occur in adults?

Bronchioles can suffer from infections regardless of age. Despite this, bronchiolitis is a disease exclusive to early childhood, particularly from birth to two years of age. When the condition occurs in adults or even children over two years of age, it becomes characterized as bronchitis. ¹

The separation and exclusivity of the nomenclature are used to tailor care to a high-risk group. Babies’ respiratory systems are extremely immature and need time to fully develop. ¹

The airways in this age group are narrow, united and do not have all the defense mechanisms that an adult’s respiratory system has. Furthermore, little ones have very limited immunity. The younger they are, the more vulnerable they are to pathogens and infections. ¹

What is the difference between bronchiolitis and pneumonia?

While bronchiolitis is the infection of the bronchioles in children under two years of age, pneumonia is a severe infection that affects the lungs, especially the pulmonary alveoli.  ^{1 2}

The alveoli are small pockets of fine connective tissue, which are at the end of the bronchial branches. They are responsible for inflating and effectively carrying out gas exchange, supplying oxygen and removing carbon dioxide from the bloodstream.  ^{1 2}

 

Considering the fragile health of newborns and babies under two years of age, both conditions represent severe threats. The symptoms presented are also similar, including runny nose, cough, shortness of breath and whistling when breathing.  ^{1 2}

The difference is that in bronchiolitis the risk has to do with obstruction of the airways, which prevents the maintenance of adequate air flow during inhalation and exhalation movements.   ^{1 2}

Pneumonia, in addition to congesting the respiratory system, can impair the elasticity of the alveoli, minimizing their ability to inflate and deflate.   ^{1 2}

Another way of distinguishing between conditions concerns the cause. In bronchiolitis, as we will see later, we have a series of different viruses on the list of main culprits. On the other hand, pneumonia is most often caused by bacteria, although it can also occur due to viral and fungal infections.  ^{1 2}

What causes bronchiolitis?

In general, we can say that the cause of childhood bronchiolitis is the infection of the bronchioles by some type of respiratory virus. Among the main culprits, we can mention respiratory syncytial virus, rhinovirus and parainfluenza. ¹

These microorganisms may also be responsible for causing colds in babies and young children. ¹

It is also important to highlight that this is a contagious disease. Thus, a child can contract the virus by inhaling droplets contaminated with the virus, dispersed in the air by a sick person. ¹

In most cases, the pathogen invades the upper airways and, little by little, spreads to the bronchi and bronchioles. This process occurs quite easily, as the child’s body does not have adequate defense systems to prevent the virus. ¹

When microorganisms invade epithelial tissue cells, they cause superficial necrosis, which serves as a trigger for the inflammatory process. One of the main characteristics of this reaction is the formation of local edema, an accumulation of fluid between the layers of the mucosa that leaves the region swollen. ¹

As a result of the creation of edema, the so-called exudate occurs, which is the leakage of this fluid or inflammatory secretion into the respiratory ducts. It is a sign that the injury is being treated by the body. However, due to the location affected and the fragile health of the little ones, it requires special attention if it causes excessive or total obstruction. ¹

Children’s bronchiolitis symptoms

In practice, childhood bronchiolitis begins as a cold or respiratory allergy. After a few days, breathing begins to be affected and the general condition tends to get a little worse. Symptoms of childhood bronchiolitis are usually ¹ :

• running nose;
• cough;
• fever;
• short or difficult breathing;
• whistling in the chest when breathing;
• nasal congestion.

The initial phase usually lasts between two and three days. After this period, the most notable respiratory symptoms appear. ¹

In most cases, symptoms are mild and do not seriously affect the baby’s appetite and mood. However, some children may become more agitated and irritable than normal, develop ear infections, have apnea and have difficulty drinking liquids. ¹

These secondary inflammations occur due to the proximity between the tissues of the middle ear, eyes, mouth and nostrils.  ¹

In these more serious conditions, there may also be a decrease in oxygen in the body, causing the child to have a blue mouth. Therefore, it is recommended to seek medical attention urgently to properly treat the case. ¹

Read also: Cough and back pain: causes + symptoms + warning signs

The first signs of bronchiolitis in babies

The first signs of bronchiolitis in babies are rhinorrhea, sneezing attacks, sporadic coughing and low-grade fever. It is only after a few days that the condition worsens. At this stage, expectoration becomes more frequent and wheezing may occur during breathing. ¹

When noticing these small warnings, it is recommended to seek medical attention to avoid taking any risks. Although the situation is potentially delicate, it is a preventive measure, considering that the condition does not always impact the child’s daily life. ¹

For example, many babies with bronchiolitis remain active, interacting a lot with the people and objects around them, with a good appetite and happy. All of this can happen even when the chest appears well loaded and breathing seems accelerated. ¹

Another factor worth mentioning is that the obstruction is more prominent on expiration than on inspiration. In other words, bronchiolitis makes movement to eliminate carbon dioxide more difficult than it is to capture oxygen from the environment. ¹

This causes air to become trapped in the alveoli, without being able to release properly. The breathing frequency increases, which is called tachypnea, and the retraction in the chest in an attempt to expel air becomes more marked.  ¹

What are the risk factors for the disease?

Among the risk factors, we can mention the case of premature children or children who were not adequately breastfed, as well as cases of congenital cardiorespiratory problems and passive smoking, even if the mother only smoked during pregnancy. ¹

Cases of bronchopulmonary dysplasia, a respiratory disease that is usually caused by prolonged mechanical ventilation in premature babies, is another factor associated with bronchiolitis. It is even a condition that can increase the risk of children having to be hospitalized. ¹

Other episodes that may suggest that the condition requires hospitalization are ¹ :

• considerable increase in apparent respiratory discomfort;
• the baby appears increasingly ill, showing fatigue, lethargy or cyanosis (bluish skin due to lack of oxygenation);
• hypoxemia, low oxygen concentration in the bloodstream, also known as low arterial blood saturation;
• Difficulty taking liquids and food orally.

If the condition eventually worsens over time, the child becomes increasingly apathetic, irritable and inconsolable. Appetite and responsiveness are greatly affected, as there is an imbalance in gas exchange, which reduces energy production in cells. ¹

How is bronchiolitis diagnosed?

To diagnose childhood bronchiolitis, a doctor can assess symptoms during a simple physical exam. It is also common to measure blood oxygenation by performing pulse oximetry, placing a sensor on the baby’s fingers. ¹

Clinical evaluation is usually enough to make an adequate diagnosis. Additional measures complement the doctor’s interpretation, but treatment does not depend on these tests to be started. ¹

In more serious cases, when there is a need to identify the virus causing the infection and how it is affecting the lungs, a mucus sample may be collected or a chest x-ray may be taken. ¹

 

X-rays of more severe cases usually show hyperinflated lungs, retraction or depression in the diaphragm and hilar prominence, which occurs when the blood vessels of the respiratory membrane are more dilated and marked on the imaging exam. ¹

The antigen test, carried out to identify the pathogen responsible for the condition, is generally aimed at detecting respiratory syncytial virus (RSV). Other tests of this kind are only indicated when secondary infections are suspected, depending on the doctor’s opinion. ¹

How to treat childhood bronchiolitis?

As it is a mild infection in most cases, the way to treat bronchiolitis includes a series of home care, focusing mainly on relieving symptoms, ensuring breastfeeding and fluid intake. ¹

The use of antibiotics is not recommended, as these medications are not effective in combating the virus. The exception is when the baby has a bacterial infection along with bronchiolitis. ¹

Home treatment for bronchiolitis

In general, home treatment for bronchiolitis consists mainly of drinking liquids, and it is important to offer water to the child, in small and frequent doses, to ensure hydration and help clean and humidify the airways. ¹

Breast milk is great for keeping the child well nourished and providing antibodies so that the body can fight the infection properly, as is the use of infant formula. ¹

There are medications that can help treat bronchiolitis, relieving some of its symptoms, but it is essential that they are prescribed by a doctor, defining the correct formula, dosage and duration for the medication. As an example, we can cite ^{1 3} :

• anti-flu: medicines that combine antipyretic, anti-allergic and analgesic action, treating the main symptoms of flu, colds and other respiratory viruses at once;
• corticosteroids: vasodilators that help relieve airway congestion, combating obstruction and facilitating air flow;
• Children’s cough syrup with phlegm : there are cough syrup options that can help with expectoration and thinning of phlegm, reducing triggers that make a child cough a lot.

Hospital treatment of bronchiolitis

In most cases, symptoms improve within seven days. If this does not happen or the condition presents more worrying signs, such as very rapid breathing, blue mouth, refusal to drink liquids and food, hospitalization may be necessary. ¹

In these situations, supportive therapy involves hydration and intravenous medication, as well as administration of oxygen and constant monitoring of blood levels. ¹

Although they are not widely used for bronchiolitis, your doctor may prescribe bronchodilators to relieve wheezing and make breathing easier. He can also administer active ingredients to control inflammation and alleviate symptoms. ¹

Is bronchiolitis curable?

Bronchiolitis follows the pattern of other respiratory infections and is a self-limiting disease. This means there is no specific cure. Treatment is aimed at relieving the child’s symptoms and discomfort, in addition to trying to preserve the child’s body to limit complications and sequelae. ¹

In most cases, the condition improves “on its own”, based on the action of the immune system. Symptoms disappear in less than a week, but a persistent cough may occur for a period after improvement. ¹

However, we must highlight that there are risks of the condition leaving babies more vulnerable and fragile for a certain period of time, until the body recovers completely. ¹

As mentioned, hospitalization is reserved only for premature children or those who already suffer from another illness, mainly heart disease, immunodeficiency or even bronchopulmonary dysplasia. ¹

How to prevent bronchiolitis?

Now that we’ve talked about how to treat bronchiolitis, let’s look at the main measures to prevent this and other respiratory infections, especially in early childhood. ^{1 4}

Offer plenty of water

Encouraging hydration from an early age is a good way to avoid respiratory problems and even some complications caused by them, such as dehydration. Fluid replacement helps keep the airways moist and protected, in addition to contributing to several important biological functions, including mucus production, cell renewal and immune responses. ⁴

In the first six months of life, only breast milk and water should be offered to the child. After this period, with the introduction of solid foods, the inclusion of teas and juices begins to be recommended.  ⁴

To find out what you can give your child and the safe amounts so as not to harm child development, talk to your pediatrician. ⁴

Increase breastfeeding frequency

We previously mentioned that babies up to 24 months old who are not breastfed properly are at greater risk of developing bronchiolitis and similar health problems. Therefore, we can conclude that increasing the frequency of offering the breast to the child to breastfeed can encourage adequate breastfeeding. ⁴

This is because breast milk is the main source of nutrition in early childhood and also serves to provide antibodies and other defense cells, complementing the development of the immune system early in life. ⁴

Avoid closed or crowded environments

Closed and crowded environments may have a higher concentration of airborne pathogens in circulation. These may include: the Influenza virus, which causes the flu, the coronavirus, which causes Covid-19, and RSV, which is mainly responsible for childhood bronchiolitis. ⁴

As the health of little ones is more fragile, it is recommended that they avoid visiting places with these characteristics, especially newborns and premature babies. ⁴

Keep the environment ventilated and clean

You should keep the child in a clean, well-ventilated and, preferably, uncrowded environment. This can reduce the risk of respiratory infections and allergic reactions, as it stimulates air renewal and limits the concentration of allergens and pathogens in circulation. ⁴

Avoid contact with people who have symptoms

If you need to visit a sick person who is showing symptoms of a respiratory infection, it is best to leave your young child at home. Furthermore, avoid excessive exposure, wear a mask and prefer open or well-ventilated places. ⁴

Likewise, if the child has symptoms, avoid contact with others of the same age to prevent the spread of the virus. ⁴

Avoid sharing personal objects

Personal objects, such as cutlery, glasses and toothbrushes, should not be shared under any circumstances, especially when they belong to children.

This measure prevents the indirect transmission of pathogens, which can happen when the saliva of an infected person contaminates any surface and is subsequently carried into the body of a healthy individual through the hands. ⁴

Sanitize toys and surfaces

It’s no secret that babies love to put everything in their mouths, including toys, pacifiers and other items within their reach. Therefore, to prevent them from catching a virus or bacteria in this way, it is recommended to sanitize toys and nearby surfaces frequently. ⁴

Preferably, this habit should be carried out right after the child’s interaction, that is, as soon as he stops playing. Knowing that it is not always possible to be so agile, try to set aside time to take this precaution, even if it is once a day. ⁴

Caring for and teaching children about personal hygiene

Practicing personal hygiene is crucial to preventing respiratory pathogens. From an early age, it’s worth teaching your children about the importance of simple habits, such as washing their hands correctly. Furthermore, a good way to encourage this care in little ones is by setting an example, so be sure to wash your hands when dealing with the child. ^{1 4}

Give palivizumab injections

There is no vaccine to prevent respiratory syncytial virus or any other pathogen that causes bronchiolitis. However, there is an alternative reserved for high-risk cases, which is the administration of palivizumab injections, a medication containing antibodies against RSV. ³

The application must be monthly and is not capable of completely preventing infection, it is only intended to prevent very serious conditions and reduce the need for hospitalization. ³

Discover Benetosse for cough relief

Benetosse is a syrup aimed at relieving productive coughs, capable of acting as an expectorant, fluidifier and antitussive. The product is suitable for adults and children over two years of age, developed from the natural extract of Hedera helix. ⁵

Visit the official Benetosse page and find out more!

Conclusion

Thus, we conclude the post on childhood bronchiolitis. We hope that the information was useful in clarifying your doubts, reducing your concerns and indicating the best way to treat the disease.

Remember that fluid intake is very important, especially to combat the risk of dehydration. Furthermore, follow the doctor’s instructions and monitor the condition so that your child improves quickly and does not have any complications.