Respiratory syncytial virus is one of the leading causes of lower respiratory infection in infants worldwide. In most babies, it causes a mild illness that settles at home. In some, particularly those under six months or born prematurely, it can lead to bronchiolitis severe enough to require oxygen or feeding support. Understanding RSV in Babies helps parents recognise when a cold has moved into the chest and when it needs medical attention.

What Is RSV and How Does It Cause Bronchiolitis?

RSV is an RNA virus that infects the respiratory tract. Almost all children are infected at least once by the age of two, and reinfection throughout life is common.
In infants, the virus spreads from the nose to the small airways called bronchioles. It causes inflammation, swelling of the airway lining, increased mucus production and shedding of dead cells into the airway. Because infant bronchioles are extremely narrow, this debris and swelling obstruct airflow, trap air in the lungs and impair oxygen exchange. This condition is bronchiolitis, most commonly seen in children under two years, with a peak between two and six months of age.

How Does RSV Spread, and Which Babies Are at Higher Risk?

RSV spreads through respiratory droplets and direct contact with contaminated hands or surfaces, where it can survive for several hours. The incubation period is typically four to six days, and infected infants may shed the virus for one to three weeks.

Risk factors for severe disease include:
●    Age under six months, especially under three months
●    Prematurity, particularly birth before 29 to 32 weeks
●    Chronic lung disease of prematurity
●    Congenital heart disease with significant haemodynamic effects
●    Immunodeficiency
●    Neuromuscular conditions affecting the ability to clear secretions
●    Exposure to tobacco smoke
●    Older siblings attending school or day care

What Are RSV Bronchiolitis Symptoms in Infants?

RSV bronchiolitis symptoms in infants typically progress over several days:
●    Days 1 to 3: Rhinorrhoea, nasal congestion, mild cough and low-grade fever.
●    Days 3 to 5: Symptoms often peak, with increased cough, fast breathing, wheeze or crackles, nasal flaring, subcostal or intercostal recession, and difficulty feeding.
●    After day 5 to 7: Gradual improvement in most infants, though cough can persist for up to four weeks.

Apnoea, meaning pauses in breathing, may occur in young infants, particularly those under two months or born prematurely, and can sometimes be the first sign of infection.

How Do I Know If My Baby Has RSV or a Normal Cold?

A common cold remains in the upper airway. The baby may have a blocked nose and mild cough but continues to feed adequately and breathes without effort.

Signs that suggest lower airway involvement include:
●    Breathing rate noticeably faster than normal (60 or more breaths per minute in babies under two months, 50 or more between 2 and 12 months)
●    Audible wheeze or crackling
●    Chest wall recession between or below the ribs
●    Head bobbing or grunting
●    Feeding reduced to less than half of usual intake
●    Noticeably fewer wet nappies
Testing is needed to confirm RSV specifically, but these signs indicate the need for medical review regardless of the virus involved.

How Is Bronchiolitis Diagnosed?

Bronchiolitis is diagnosed clinically based on history and examination. Paediatricians assess respiratory rate, work of breathing, chest findings, hydration and oxygen saturation by pulse oximetry.
Rapid antigen or PCR tests on nasal swabs may be used in hospital to confirm RSV and guide infection control. Chest X-ray and blood tests are not routinely recommended but may be done if the diagnosis is uncertain, bacterial pneumonia is suspected or the baby is severely unwell.

What Is the Treatment for RSV Bronchiolitis?

Management is supportive. International guidelines, including those from the American Academy of Pediatrics, do not recommend routine use of bronchodilators, corticosteroids, antibiotics or chest physiotherapy for typical bronchiolitis, as studies show little benefit.
Home care, as advised by a doctor:
●    Saline nasal drops and gentle nasal suction, especially before feeds
●    Small, frequent feeds to maintain hydration
●    Keeping the baby slightly upright during feeds
●    Paracetamol for fever only in a doctor-prescribed dose
●    A smoke-free environment

Hospital care may include:
●    Supplemental oxygen when saturation remains low
●    High-flow nasal cannula oxygen or CPAP for increasing respiratory distress
●    Nasogastric tube feeding or IV fluids when oral intake is inadequate
●    Continuous monitoring of oxygen and breathing
●    Mechanical ventilation in a small number of severe cases

When Does a Baby with RSV Need Hospital Care?

Hospital admission is generally considered for:
●    Persistently low oxygen saturation
●    Moderate to severe respiratory distress
●    Apnoea
●    Inadequate feeding or dehydration
●    Age under three months, prematurity or significant underlying heart or lung disease
●    Parental concern or inability to monitor safely at home

Parents seeking the best pediatric hospital for RSV treatment in Jaipur should look for 24-hour paediatric cover, oxygen and non-invasive respiratory support, and access to NICU or PICU care.

When Should Parents Seek Medical Help?

See a paediatrician promptly for fast breathing, wheeze, reduced feeding or fewer wet nappies. Go to emergency immediately for cyanosis, apnoea, severe chest recession, grunting, extreme lethargy or fever in a baby under three months.

How Can RSV Be Prevented in Infants?

●    Wash hands before handling the baby.
●    Keep people with respiratory symptoms away from young infants.
●    Clean toys and frequently touched surfaces.
●    Limit exposure to crowded places during peak season.
●    Breastfeed where possible.
●    Avoid tobacco smoke exposure.

Long-acting monoclonal antibodies for infants and maternal RSV vaccination during late pregnancy are now used in several countries. Ask your paediatrician or obstetrician about current availability and suitability.

Conclusion

Most babies with RSV recover with supportive care at home, but close attention to breathing and feeding is essential, especially in young and premature infants. Understanding RSV in Babies helps parents to recognise when hospital support is needed. If your baby's breathing or feeding changes, consult a paediatrician without delay. Maternite Hospitals offers neonatology, a Level III NICU and a dedicated PICU for infants who need specialised care.