RSV (Respiratory Syncytial Virus) in Children: Symptoms, Risk Factors and Treatment

What Is RSV?

Respiratory syncytial virus (RSV) is one of the most common causes of lower respiratory tract infections, especially in babies and young children. RSV infection can range from a mild upper respiratory infection to more serious conditions such as bronchiolitis and pneumonia. RSV is a common virus that can infect all babies: about 90% of babies encounter RSV by the age of 2. Worldwide, it is the leading cause of hospital admission among babies.

RSV infection can be more severe, especially in the first year of life. Premature babies, children with chronic lung disease and babies with congenital heart disease are at higher risk. Even without any risk factors, however, all babies under 6 months of age during the season are at risk of RSV infection.

RSV infections are more common in autumn and winter. The seasonal pattern varies by region; in Turkey, the season can be said to run from October to March.

How Does RSV Spread in Children?

RSV is a highly contagious respiratory virus. It usually spreads:

• Through droplets from coughing and sneezing
• Through close contact
• After contact with contaminated surfaces
• Via dirty hands

RSV can survive on surfaces for hours, so the risk of transmission is higher, especially in nurseries and schools.

RSV is usually most contagious in the first days after symptoms begin. In babies, the contagious period may be longer.

What Are the Symptoms of RSV in Children?

RSV infection usually starts with upper respiratory symptoms and can progress to a lower respiratory infection in some children.

Early Symptoms of RSV

• Runny nose
• Mild fever
• Cough
• Sneezing
• Loss of appetite
• Irritability

Progressive Symptoms of RSV

• Wheezing
• Rapid breathing
• Difficulty breathing
• Chest retractions
• High fever
• Feeding difficulties
• Apnoea (pauses in breathing)
• Bluish lips

RSV infection can be more serious, especially in young babies. RSV is one of the most common causes of bronchiolitis.

Symptoms of RSV in Babies

In babies, RSV infection may present differently:

• Feeding difficulties
• Apnoea (pauses in breathing)
• Rapid breathing
• Bluish skin
• Marked irritability
• Drowsiness

These signs should be taken especially seriously in babies under 6 months.

How Long Does RSV Last?

RSV infection usually follows this course:

• Symptoms increase over the first 3–5 days
• Recovery begins within 7–10 days
• The cough may last 2–3 weeks

In some children, wheezing in particular may persist for longer.

Which Children Get More Severe RSV?

RSV can be more serious in some children. Children in risk groups include:

• Babies under 2 years
• Premature babies
• Children with chronic lung disease
• Children with congenital heart disease
• Children with a weakened immune system

RSV infection should be monitored closely in these children.

RSV and Bronchiolitis

RSV is the most common cause of bronchiolitis in babies. Bronchiolitis is inflammation of the small airways and presents with:

• Wheezing
• Cough
• Difficulty breathing
• Rapid breathing

Bronchiolitis is most common in children under 2.

RSV bronchiolitis is dangerous because it can require intensive care, especially in babies under 6 months.

RSV and Allergic Asthma

In children prone to asthma, RSV can cause lasting changes in the lungs and increase the likelihood of developing asthma. It can be said that RSV infection managed at home increases the likelihood of a diagnosis of wheezing/asthma 4.5-fold, and RSV infection requiring hospital admission 8–9-fold.

How Is RSV Diagnosed?

RSV is usually diagnosed on the basis of clinical findings. When necessary:

• A nasal swab test
• Blood tests
• A chest X-ray

may be used.

How Is RSV Treated?

In most cases no specific antiviral treatment is needed for RSV. Treatment is usually supportive:

• Increasing fluid intake
• Fever control
• Nose cleaning
• A humid environment
• Rest

In severe cases:

• Oxygen therapy
• Hospital admission
• Fluid therapy

may be needed.

How Can RSV Be Prevented?

During the season, the following measures are recommended to protect against RSV:

• Washing hands frequently
• Avoiding contact with sick people
• Avoiding crowded places
• Cleaning toys
• Keeping babies away from sick people

These measures are especially important for babies in risk groups.

However, the main protection is vaccination or antibody administration before the season starts.

If the mother is vaccinated against RSV during pregnancy (after week 32), the baby is protected against RSV during its first season after birth. For the vaccine to work, there must be at least 2 weeks between the mother’s vaccination and the birth. In Turkey it is a private, optional vaccine.

If the mother did not have the chance to receive the adult RSV vaccine during pregnancy, it is recommended that babies who will be under 6 months during the season receive an RSV immunoglobulin (antibody) at the beginning of October.

In previous years there was an antibody available only for high-risk babies – those born very prematurely or with chronic heart or lung disease. This very expensive antibody could be obtained with a medical report and was given monthly, for a total of 5 doses.

For some time now, however, a newer antibody has been available in Turkey that can be given to all babies, even those not in a specific risk group. It is also relatively expensive and available privately, and a single dose protects for the whole season. The key point is the baby’s weight: babies under 5 kg need a 50 mg dose, while babies over 5 kg should receive 100 mg.

These antibodies protect babies from hospital admission for RSV-related lung infections during their first season by 85.9%. According to study results, in babies who received the antibody in their first season, this protection continues at 55.3% even in the following season.

Conclusion

RSV is a common respiratory infection, especially in babies and young children. Although it is usually mild, it can cause serious breathing problems in some children.

That is why vaccination during pregnancy or antibody administration in newborns is the cornerstone of prevention.

Recognising early symptoms and appropriate follow-up play an important role in managing RSV infection.

References

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