How Long Does RSV Illness Last in Kids?
Key takeaways:
Most children get sick with respiratory syncytial virus (RSV) at least once before they’re 2 years old.
RSV symptoms usually get worse over the first few days of illness and peak around day 5. Children are more likely to need medical attention when RSV symptoms are at their worst.
Once RSV symptoms peak, they slowly get better over time. Children are usually sick for 7 to 10 days from RSV.
Respiratory syncytial virus (RSV) is the most common childhood viral illness in the world. It affects nearly 90% of children within their first 2 years of life. RSV illness is also the most common reason babies need hospital care. But even mild RSV illness can make infants and children uncomfortable.
If your child is sick with RSV, you may wonder how long it’ll take for them to feel better. Here’s how long RSV illness typically lasts in kids.
How long does RSV last in kids?
RSV illness typically lasts 7 to 10 days. But some children can be sick longer — especially if they have underlying medical conditions or were born prematurely.
Your child’s symptoms will change over the course of their illness. Childhood RSV symptoms usually follow a typical pattern. This pattern can help you figure out when they’re likely to recover. Here’s what a typical childhood RSV timeline looks like.
RSV symptoms timeline in babies
Babies often have different symptoms than toddlers and older children. Their illness timeline looks like the following.
Babies develop symptoms of RSV illness between 2 and 5 days after coming in contact with the virus. During this time, your baby won’t show any symptoms. But if you know your child was exposed to the RSV virus, then you can start counting the days until symptoms are likely to start.
Babies develop mild symptoms when they first get sick. During the first 2 to 3 days of RSV illness, your baby may experience:
Fever
Cough
Runny nose
Congestion
Trouble eating due to congestion
RSV symptoms will usually get worse before they get better. Symptoms are at their worst during days 3 to 5 of their illness. Your baby is more likely to need medical attention when they reach this point in their illness.
During this time, your baby may develop severe RSV symptoms like:
Worsening congestion
Fast breathing
Trouble breathing
Use of extra muscles to breathe
Nasal flaring
Wheezing
Inability to eat
Fewer wet diapers
Trouble breathing can be a sign of bronchiolitis or other lower respiratory tract infections, like pneumonia. Seek immediate medical care if your child develops difficulty breathing. Many babies with bronchiolitis or pneumonia need care in a hospital.
After their RSV symptoms peak, babies begin to recover. You’ll notice that your baby’s symptoms slowly start to get better and then go away completely. This process can take about a week. In total, your baby may be sick for about 10 days. Some babies recover slightly faster, while others may be sick for 2 weeks. Babies with underlying medical conditions may be sick for longer than 2 weeks.
Babies can remain contagious longer than older children and adults when they’re sick with RSV. Your baby can spread RSV to others for up to 4 weeks after symptoms first appear.
RSV symptom timeline in toddlers and children
RSV symptom timeline in toddlers and preschool aged children follows this pattern.
Toddlers and preschool-aged children develop symptoms of RSV illness 2 to 5 days after coming in contact with the virus. Children won’t have any symptoms during this time. If you know your child was exposed to the RSV virus, then you can start counting the days until their symptoms are likely to start.
Children and toddlers often start with mild symptoms during the first three days of their illness. Your child’s RSV symptoms can look a lot like a common cold. Some common symptoms of early RSV illness include:
Fever
Cough
Runny nose
Congestion
Sneezing
Children who are sick with RSV will get worse before they get better. RSV symptoms are at their worst during days 3 to 5 of illness. Your child is more likely to need medical attention when they reach this point in their illness.
During this time, your child may develop:
Worsening congestion
Fast breathing
Less interest in eating
Reduced urine output
Less interest in activities
Toddlers and older children are less likely than babies to develop bronchiolitis when they’re sick with RSV. But they may develop bacterial infections like pink eye, ear infections, or pneumonia on top of their RSV illness. If your child has a history of asthma, they may develop an asthma exacerbation (asthma attack) while they’re sick with RSV.
Seek immediate medical care if you notice that your child has trouble breathing during the peak of their RSV illness. You should also seek care if your child isn’t eating or drinking normally, which could lead to dehydration.
Toddlers and children gradually start to recover after their RSV symptoms reach their peak. You’ll notice their symptoms start to slowly get better and then go away completely. This process can take about a week.
Most children are sick for about 10 days. Some may recover faster, while others may take longer.
Children and toddlers aren’t contagious as long as babies. Usually, kids are contagious for up to a week after they develop RSV symptoms.
How long does it take to recover from RSV?
In general, it takes between 10 and 14 days to recover from RSV. But every child’s recovery is different.
Some children recover faster and are only sick for about a week. Others can take longer to recover. Your child may take longer to recover if they:
Were born prematurely
Have a history of heart or lung disease
Have a weakened immune system
Are younger than 6 months old
Looking for ways to help your child feel better? Our experts review the best treatments for childhood RSV.
RSV illness is preventable. Here’s how Beyfortus can help.
Have more questions about RSV? Our Childhood RSV Guide has the answers you’re looking for.
When to get help for RSV symptoms in kids
Most babies and children only develop mild symptoms from their RSV illness. You can treat your child’s mild RSV symptoms at home with remedies like:
Over-the-counter (OTC) fever reducers
Fluids
Humidifiers
Nasal saline
These home remedies can help keep your child comfortable while their immune system fights the RSV virus.
But some children develop severe RSV symptoms and need medical attention. Your child is more likely to need medical attention during the peak of their illness. RSV symptoms are at their worst during days 3 to 5 of your child’s illness. Seek medical care right away if your child develops these symptoms during peak RSV illness:
Rapid breathing
Trouble breathing
Wheezing
Inability to eat or drink
Making less urine
More sleepy than usual
Fever that’s getting worse (higher)
Contact your child’s healthcare team if you think their symptoms are getting worse at any time or they develop any new symptoms.
The bottom line
RSV is a common cause of childhood illness. Many children develop mild symptoms that can be treated at home. But some children develop more severe symptoms that need treatment in a hospital. RSV symptoms typically start off slowly and peak around days 3 to 5 of illness. Children are more likely to need medical attention during this period.
RSV illness lasts about 10 to 14 days in kids. While some recover faster, others may be sick for longer. Children with a history of prematurity, heart or lung conditions, or a weakened immune system may take longer to recover from their RSV illness.
Why trust our experts?
References
Caserta, M., et al. (2024). RSV: When it’s more than just a cold. HealthyChildren.org.
Children’s Hospital Los Angeles. (2022). RSV: Everything you need to know.
Jain, H., et al. (2023). Respiratory syncytial virus infection in children. StatPearls.
Munro, A. P. S., et al. (2023). The disease burden of respiratory syncytial virus in infants. Current Opinion in Infectious Diseases.
Otomaru, H., et al. (2021). Risk of transmission and viral shedding from the time of infection for respiratory syncytial virus in households. American Journal of Epidemiology.
Ruiz-Galiana, J., et al. (2024). Respiratory syncytial virus: A new era. Revista Española de Quimioterapia.
Singh, S., et al. (2023). Respiratory syncytial virus infections in neonates: A persisting problem. Newborn.
