RSV in Children: Symptoms, Treatment & When to Seek Care

What Is RSV (Respiratory Syncytial Virus)?

RSV (Respiratory Syncytial Virus) is a highly contagious virus that causes respiratory infections in children and adults. Nearly all children are infected with RSV by age 2. While most children develop only mild cold symptoms, RSV is the leading cause of hospitalization in infants under 1 year old worldwide.

RSV stands for Respiratory Syncytial Virus, named for the characteristic fusion of infected cells that the virus causes in laboratory cultures. This common virus circulates globally and causes seasonal outbreaks, typically during fall, winter, and early spring in temperate climates. The virus primarily targets the respiratory tract, causing inflammation in the nose, throat, and lungs.

For most healthy older children and adults, RSV infection resembles a common cold and resolves without complications. However, in infants—particularly those under 6 months of age—RSV can cause serious lower respiratory tract infections including bronchiolitis (inflammation of the small airways in the lungs) and pneumonia. These conditions can lead to breathing difficulties that require hospitalization and, in severe cases, intensive care.

The burden of RSV disease is substantial: globally, RSV causes an estimated 33 million cases of acute lower respiratory infection in children under 5 years old each year, resulting in approximately 3 million hospitalizations and 100,000 deaths worldwide. In developed countries with access to modern medical care, death from RSV is rare, but the virus remains a leading cause of infant hospitalization during RSV season.

Why Are Some Children at Higher Risk?

Certain groups of children face significantly higher risks of severe RSV disease. Understanding these risk factors helps parents and healthcare providers identify children who may benefit from preventive measures and closer monitoring during RSV season.

The most important risk factor is age: infants under 3 months old have the highest risk of severe illness because their airways are small, their immune systems are immature, and they may have difficulty clearing secretions from their airways. Premature infants (born more than 5 weeks early) face additional risks because their lungs may not be fully developed and they may lack protective antibodies that full-term babies receive from their mothers during the final weeks of pregnancy.

Children under 2 years with certain underlying medical conditions also face elevated risks:

• Chronic lung disease: Including bronchopulmonary dysplasia (BPD), a condition affecting premature infants' lungs
• Congenital heart disease: Especially conditions that affect blood flow through the heart and lungs
• Neuromuscular disorders: Conditions affecting muscle strength and coordination, which can impair coughing and clearing secretions
• Immunodeficiency: Any condition or treatment that weakens the immune system

What Are the Symptoms of RSV in Babies and Children?

RSV symptoms typically begin like a common cold with runny nose, congestion, cough, and fever. In infants under 6 months, symptoms can progress to breathing difficulties including rapid breathing, wheezing, nasal flaring, and chest retractions. The most concerning symptoms are apnea (breathing pauses), extreme lethargy, and difficulty feeding.

RSV infection follows a characteristic progression that parents should understand. Symptoms typically begin 3-5 days after exposure to the virus (the incubation period). The illness usually starts with upper respiratory symptoms before potentially progressing to involve the lower respiratory tract in vulnerable children.

The initial symptoms of RSV closely resemble a common cold and include a runny nose with clear or thick mucus, nasal congestion, sneezing, and a mild cough. Many children also develop a low-grade fever during this early phase. Older children and adults often experience only these mild symptoms, which resolve within 1-2 weeks without complications.

In infants, particularly those under 6 months old, the infection can progress to involve the lower airways, causing bronchiolitis or pneumonia. This progression typically occurs 2-4 days after the initial cold symptoms appear. Children are usually most ill during days 4-6 of the illness, after which gradual improvement typically begins.

Breathing Difficulties and Warning Signs

When RSV spreads to the lower airways, it causes inflammation and mucus production that can significantly impair breathing. Parents should watch carefully for signs of respiratory distress, which indicate the child needs medical evaluation.

Rapid breathing (tachypnea) is often the first sign that RSV has affected the lower airways. In infants under 1 year, breathing rates above 60 breaths per minute are concerning. Parents can count breaths by watching the chest rise and fall for 30 seconds and multiplying by two. However, any breathing that looks labored or concerning warrants medical evaluation regardless of the exact rate.

Retractions are another important warning sign. These occur when the skin visibly pulls inward with each breath, indicating the child is working hard to breathe. In infants, retractions are most visible below the ribcage (just above the belly), between the ribs, and at the notch above the breastbone. Parents may notice the child's belly moving in and out prominently with each breath.

Wheezing—a high-pitched whistling sound during breathing, especially when exhaling—indicates narrowing of the small airways. Nasal flaring, where the nostrils widen with each breath, is another sign of respiratory distress as the child attempts to get more air into the lungs.

Apnea: A Critical Warning Sign in Young Infants

Apnea—episodes where breathing stops completely for several seconds—is a particularly concerning symptom in young infants with RSV. This complication occurs most frequently in babies under 2 months old and in premature infants. Importantly, apnea can occur early in RSV infection, sometimes even before other respiratory symptoms become prominent.

During an apneic episode, the infant may appear to pause breathing, turn pale or bluish, and become limp. These episodes can occur during sleep or while awake. Any witnessed apneic episode in an infant requires immediate emergency medical attention, even if the baby seems to recover quickly.

Feeding Difficulties

Nasal congestion and increased breathing effort can significantly impair an infant's ability to feed. Babies breathe primarily through their noses, so when the nose is blocked with mucus, they may struggle to coordinate sucking, swallowing, and breathing during feeding. This can lead to poor intake, dehydration, and fatigue.

Parents may notice their baby taking shorter feeds, pulling away from the breast or bottle frequently, or refusing to feed altogether. Decreased wet diapers (fewer than 4-6 wet diapers in 24 hours in an infant) is a warning sign of dehydration that requires medical attention.

When Should You Seek Medical Care for RSV?

Seek immediate medical care if your baby under 3 months has fever, if your child has difficulty breathing, or if your child cannot feed properly. Call emergency services immediately for any breathing pauses (apnea), blue or gray coloring, or if your child is extremely difficult to wake.

Most children with RSV can be safely cared for at home and will recover without complications. However, certain situations require prompt medical evaluation to ensure the child receives appropriate care and to prevent serious complications.

Contact your doctor or seek urgent medical care if:

• Your baby is under 3 months old and has a fever (temperature above 38°C/100.4°F)
• Your child has visible breathing difficulties (rapid breathing, retractions, wheezing)
• Your child is having trouble feeding or drinking and is producing fewer wet diapers
• Symptoms seem to be getting worse rather than improving after 4-5 days
• Your child has an underlying health condition that increases RSV risk

When you seek care, doctors will assess your child's breathing, hydration status, and overall condition. They may perform tests to confirm RSV infection and rule out other causes. Decisions about hospitalization depend on the severity of symptoms, the child's ability to feed and stay hydrated, and the presence of risk factors for severe disease.

What to Expect at the Emergency Room

If your child requires emergency evaluation, medical staff will first assess vital signs including heart rate, breathing rate, oxygen saturation (using a small device clipped to the finger or toe), and temperature. They will examine your child's breathing patterns, listen to the lungs, and assess hydration.

An RSV test may be performed using a nasal swab—a thin, flexible stick is gently inserted into the nose to collect a mucus sample. Results from rapid tests are typically available within 15-30 minutes. While waiting for results, treatment focuses on supporting breathing and hydration.

How Can You Care for a Child with RSV at Home?

Home care for mild RSV focuses on keeping the child hydrated, clearing nasal congestion with saline drops and gentle suctioning, elevating the head during sleep, and monitoring for warning signs. Most children recover within 1-2 weeks with supportive care alone.

When RSV symptoms are mild and your child is feeding adequately and breathing comfortably, home care is appropriate and effective. The goals of home treatment are to keep your child comfortable, maintain hydration, ease breathing difficulties, and monitor for any signs that the illness is worsening.

Hydration is the cornerstone of RSV care at home. Babies with RSV need to drink frequently, even if they take smaller amounts at each feeding. Breast milk or formula provides both hydration and nutrition for infants. For breastfed babies, nurse more frequently than usual. For formula-fed babies, offer smaller, more frequent feedings if the baby seems tired or struggling with larger volumes.

If your baby is too congested to feed effectively from the breast, you may need to pump breast milk and offer it in a bottle temporarily. This can make feeding easier because bottle feeding requires less effort than breastfeeding. Once the baby recovers, you can return to breastfeeding normally—milk supply will recover with increased nursing.

Clearing Nasal Congestion

Keeping your child's nose as clear as possible helps with both breathing and feeding. Saline (saltwater) nasal drops help loosen thick mucus and can be used multiple times throughout the day, especially before feedings and sleep.

To use saline drops effectively: lay your baby on their back, place 2-3 drops of saline solution in each nostril, wait a minute or two for the saline to loosen the mucus, then gently suction with a bulb syringe or nasal aspirator. Squeeze the bulb before inserting the tip into the nostril, then release to create suction. Clean the bulb between uses.

For children over 1 year old, over-the-counter decongestant nasal drops may provide additional relief, but these should not be used for more than 3 days and are not recommended for infants. Always check with your pediatrician before using any medication.

Positioning and Environment

Elevating your child's head during sleep can help reduce nasal congestion and make breathing easier. For infants, place a folded towel or pillow under the mattress (not directly under the baby) to create a gentle incline. Never place loose pillows, blankets, or other soft items in a baby's crib.

Some parents find that holding their baby in an upright position, such as in a baby carrier or while sitting in a slightly reclined position, helps with congestion. Supervised time in a bouncy seat can also help.

Running a cool-mist humidifier in your child's room adds moisture to the air, which can help soothe irritated airways and loosen mucus. Clean the humidifier daily to prevent mold growth. Avoid hot-water vaporizers, which pose a burn risk.

Fever Management

Fever itself is not harmful and is actually part of the body's defense against infection. However, if your child is uncomfortable due to fever, age-appropriate fever-reducing medication can help.

For infants under 6 months, always consult your doctor before giving any medication. For older infants and children, acetaminophen (paracetamol) or ibuprofen can be used according to package directions based on your child's weight. Never give aspirin to children due to the risk of Reye's syndrome.

What Treatment Do Children Receive in the Hospital?

Hospital treatment for RSV focuses on supportive care: oxygen therapy for low oxygen levels, IV fluids or tube feeding for dehydration, and close monitoring of breathing. There are no medications that kill RSV—treatment supports the child while the immune system fights the infection.

Children hospitalized with RSV receive supportive care tailored to their specific needs. The fundamental goals are ensuring adequate oxygen delivery, maintaining hydration and nutrition, and monitoring for complications. For most children, hospital stays range from 2-5 days, though premature infants and those with underlying conditions may require longer treatment.

Oxygen Therapy

Many children hospitalized with RSV have low blood oxygen levels (hypoxemia) due to inflammation and mucus blocking their airways. Pulse oximetry—a painless monitoring device clipped to a finger or toe—continuously measures oxygen saturation. If levels fall below acceptable thresholds (typically below 90-92%), supplemental oxygen is provided.

Oxygen can be delivered through various methods depending on the child's needs. Nasal cannula (small prongs that sit in the nostrils) provides low-flow oxygen and is comfortable for most children. High-flow nasal cannula (HFNC) delivers humidified, heated oxygen at higher flow rates and can help open airways while providing oxygen. In severe cases, some children require more intensive respiratory support.

Fluids and Nutrition

Children who cannot maintain adequate oral intake may receive fluids and nutrition through alternative routes. A nasogastric (NG) tube—a thin, flexible tube passed through the nose into the stomach—allows formula or breast milk to be given directly to the stomach while the child rests. This is often preferred because it maintains gut function and provides optimal nutrition.

If NG feeding is not tolerated or the child is severely dehydrated, intravenous (IV) fluids provide hydration directly into the bloodstream. IV access also allows rapid administration of medications if needed.

Respiratory Support and Intensive Care

A small percentage of children with severe RSV require intensive care unit (ICU) admission. This is more common in premature infants, very young babies, and children with underlying heart, lung, or immune conditions.

Children with respiratory failure may require mechanical ventilation—a machine that breathes for the child while the lungs heal. Modern pediatric ICUs also use non-invasive ventilation techniques such as CPAP (continuous positive airway pressure) or BiPAP, which support breathing through a mask rather than a tube in the airway.

How Does RSV Spread and How Long Is It Contagious?

RSV spreads through respiratory droplets when infected people cough, sneeze, or breathe. It can also spread by touching contaminated surfaces and then touching the face. RSV survives on hard surfaces for hours. Children are most contagious during the first few days of symptoms but can spread the virus for 1-2 weeks.

Understanding how RSV spreads helps parents protect vulnerable children and prevent transmission to others. RSV is highly contagious, which is why nearly all children are infected by age 2—most acquire the virus from older siblings, parents, or other caregivers who may have only mild cold symptoms.

The primary mode of RSV transmission is through respiratory droplets. When an infected person coughs, sneezes, or even talks, tiny droplets containing the virus are expelled into the air. These droplets can travel several feet and infect others who inhale them or receive them on their mucous membranes (eyes, nose, mouth).

RSV can also spread through contact with contaminated surfaces. The virus survives on hard surfaces like doorknobs, toys, and countertops for several hours and on hands for about 30 minutes. If a child touches a contaminated surface and then rubs their eyes, nose, or mouth, they can become infected.

Incubation Period and Contagious Period

The incubation period for RSV—the time between exposure and symptom onset—is typically 3-5 days, though it can range from 2-8 days. Children begin shedding virus (and can spread infection to others) before symptoms appear and continue to shed virus for 1-2 weeks after symptoms begin.

Viral shedding is highest during the first few days of illness, which is when children are most contagious. However, because children can spread RSV before they show symptoms, preventing transmission is challenging. This is particularly concerning in settings like daycare centers, where one infected child can quickly spread the virus to many others.

Seasonal Pattern

In temperate climates, RSV follows a predictable seasonal pattern, with cases increasing in fall, peaking in winter, and declining in spring. The exact timing varies by region and year. Public health authorities track RSV circulation and can provide information about local RSV activity.

During peak RSV season, parents of high-risk infants should take extra precautions to limit exposure, including avoiding crowded indoor spaces and ensuring that anyone who handles the baby washes their hands and is healthy.

How Can RSV Be Prevented?

RSV prevention includes immunization with monoclonal antibodies for infants (nirsevimab/Beyfortus provides 6 months of protection), maternal RSV vaccination during pregnancy, and infection control measures like handwashing and avoiding sick contacts. High-risk infants may receive monthly palivizumab (Synagis) injections during RSV season.

Prevention strategies for RSV have advanced significantly in recent years, with new immunization options offering protection for the most vulnerable infants. Prevention approaches include both immunization to boost immunity and behavioral measures to reduce exposure.

Nirsevimab (Beyfortus) for Newborns and Infants

Nirsevimab is a monoclonal antibody that provides passive immunity against RSV. Unlike vaccines, which stimulate the body to produce its own antibodies, nirsevimab provides ready-made antibodies that immediately protect against RSV infection.

Nirsevimab is recommended for all infants in their first RSV season. It is typically given as a single injection shortly after birth (before leaving the hospital) or during a follow-up visit. The protection lasts approximately 5-6 months, covering the infant through their highest-risk period.

Clinical trials showed that nirsevimab reduces RSV-related hospitalizations by approximately 80% in healthy term and late preterm infants. The antibody treatment is well-tolerated with minimal side effects, most commonly mild reactions at the injection site.

Maternal RSV Vaccination During Pregnancy

Pregnant women can receive an RSV vaccine (Abrysvo) between weeks 32-36 of pregnancy. The vaccine stimulates the mother's immune system to produce antibodies that cross the placenta and protect the baby after birth.

For optimal protection, the vaccine should be given at least 2 weeks before delivery to allow adequate time for antibody transfer. Babies whose mothers received the RSV vaccine during pregnancy typically do not need nirsevimab, as they already have protective antibodies.

This maternal vaccination strategy is particularly valuable in regions where nirsevimab may not be readily available or affordable. It provides protection during the critical first months of life when infants are most vulnerable to severe RSV disease.

Palivizumab (Synagis) for High-Risk Infants

Palivizumab has been used for decades to protect high-risk infants against RSV. Unlike nirsevimab (which is given once), palivizumab requires monthly injections throughout RSV season because its protective effect wanes more quickly.

Palivizumab is typically reserved for the highest-risk infants, including very premature babies, infants with chronic lung disease, and those with significant congenital heart disease. The decision to use palivizumab is made by the child's physician based on specific risk factors and current guidelines.

Infection Control Measures

Basic hygiene measures remain important for preventing RSV transmission, especially for families with high-risk infants:

• Hand hygiene: Wash hands thoroughly with soap and water before touching infants. Use alcohol-based hand sanitizer when handwashing is not possible.
• Avoid sick contacts: Keep infants away from people with cold symptoms. Ask family members and visitors to postpone visits if they are unwell.
• Limit exposure to crowded indoor spaces: During RSV season, minimize trips to crowded places like shopping centers with high-risk infants.
• Respiratory hygiene: Teach older children to cover coughs and sneezes with their elbow or a tissue.
• Clean surfaces: Regularly clean frequently touched surfaces like doorknobs, toys, and countertops.

When Can Children Return to Daycare or School?

Children can return to daycare or school when they have been fever-free for 24 hours without medication and have enough energy to participate in normal activities. A lingering mild cough or runny nose is acceptable as long as the child is otherwise well and active.

Deciding when a child is well enough to return to group settings can be challenging for parents. The goal is to balance the child's recovery needs with practical family considerations while minimizing transmission to other children.

General guidelines for return to daycare or school include:

• The child has been fever-free for at least 24 hours without using fever-reducing medication
• The child has enough energy to participate in normal daily activities
• The child can eat, drink, and sleep reasonably well
• Breathing is comfortable without visible distress

A persistent mild cough or runny nose does not necessarily mean the child cannot return—these symptoms often linger for weeks after the acute illness resolves. Children who are active, eating well, and fever-free can generally participate in normal activities even with residual symptoms.

However, keep in mind that children with RSV may still be contagious for 1-2 weeks after symptom onset. While complete isolation is impractical, encourage continued good hand hygiene and respiratory etiquette (covering coughs and sneezes) to minimize spread to others.

Can RSV Have Long-Term Effects?

Children who have severe RSV bronchiolitis in infancy, especially under age 1, have an increased risk of developing recurrent wheezing and asthma later in childhood. RSV does not cause asthma but may trigger asthma in children with genetic predisposition.

While most children recover from RSV completely within 1-2 weeks, research has identified associations between severe RSV infection in early life and later respiratory problems. Understanding these potential long-term effects can help parents monitor their children and seek appropriate care if respiratory symptoms develop.

Studies consistently show that infants who experience severe RSV bronchiolitis—particularly those requiring hospitalization—have higher rates of recurrent wheezing episodes in subsequent years. Some of these children go on to develop asthma, though the relationship between RSV and asthma is complex and not fully understood.

Current evidence suggests that RSV likely does not cause asthma directly. Rather, children who develop severe RSV disease may have underlying genetic susceptibility to airway inflammation and hyperreactivity. The RSV infection may trigger or unmask this predisposition in vulnerable children.

Parents of children who had severe RSV bronchiolitis should be aware that subsequent respiratory infections, particularly colds, may trigger wheezing episodes. If your child develops recurrent wheezing after RSV infection, discuss this with your pediatrician, who can evaluate for asthma and recommend appropriate management.