RSV typically lasts one to two weeks in children, though a lingering cough can stick around longer. Most kids start with mild cold-like symptoms that peak around days three to five before gradually improving. The timeline varies depending on a child’s age, overall health, and whether the infection stays in the upper airways or moves deeper into the lungs.
Incubation and Early Symptoms
After exposure, it takes about four to six days before any symptoms appear. This incubation period is important because children can actually become contagious a day or two before they show any signs of being sick, which is one reason RSV spreads so easily through daycares and households.
The first symptoms look a lot like a common cold: runny nose, mild cough, and reduced appetite. At this stage it’s nearly impossible to tell RSV apart from dozens of other respiratory viruses. In older toddlers and school-age kids, the illness may never progress beyond this point, resolving in about a week without complications.
When Symptoms Peak
RSV often gets worse before it gets better. The illness typically intensifies a few days in, usually around days two to four after symptoms start. This is when upper respiratory symptoms like congestion and runny nose can give way to lower respiratory tract involvement: a deeper cough, wheezing, and in some cases visible difficulty breathing. Children under two are especially prone to this progression because their airways are so small that even modest swelling can cause noticeable breathing trouble.
For babies under six months, this peak period demands close attention. Nearly half of RSV-related deaths occur in infants younger than six months, and the severity of the initial infection at this age is linked to a higher risk of breathing problems later in childhood. Signs that a child is struggling include flared nostrils, rapid breathing, and the skin pulling inward between the ribs with each breath.
The Contagious Window
Children with RSV are typically contagious for three to eight days. That window opens a day or two before symptoms appear and usually closes as symptoms wind down. However, some infants and children with weakened immune systems can continue shedding the virus for four weeks or longer, even after they look and feel better. In rare cases involving immunocompromised children, such as those undergoing chemotherapy, viral shedding has been documented for months.
There’s no single CDC-specified number of days a child must stay home from daycare. The general guidance is that children with symptoms of infectious illness like RSV should stay home until they’re feeling better, and families should check with their pediatrician about timing. A practical rule: if your child still has a fever or is actively wheezing, they’re not ready to go back.
Recovery and Lingering Cough
The acute phase of RSV, meaning fever, congestion, and the worst of the breathing symptoms, generally wraps up within seven to ten days. But a dry, nagging cough can persist for two to four weeks after the main illness has passed. This post-viral cough happens because the airways remain irritated and slightly inflamed even after the virus is cleared. It sounds concerning, but as long as the cough is gradually improving and your child is eating, sleeping, and breathing comfortably, it’s a normal part of recovery.
What Hospitalization Looks Like
Most children recover from RSV at home, but a small percentage need hospital care, particularly infants who develop bronchiolitis or pneumonia. When children do require intensive care, the median stay in the ICU is roughly two days. Some children end up hospitalized for a week or longer. A large Swedish study tracking over two decades of births found that thousands of otherwise healthy, full-term infants required hospital stays of seven days or more, reinforcing that severe RSV isn’t limited to premature babies or those with underlying conditions.
Hospital treatment is mostly supportive: supplemental oxygen, fluids, and monitoring. There’s no antiviral that shortens the course of RSV in most children. Recovery after discharge usually takes another one to two weeks before a child is fully back to normal.
Long-Term Effects on Breathing
For some children, RSV’s impact extends well beyond the initial illness. Infection in the first year or two of life is associated with recurrent wheezing episodes, particularly in kids who had a severe case. These wheezing episodes are often triggered by subsequent viral infections and are most common in children under five.
The good news is that for most children, this is a temporary pattern. Research following large groups of children over time shows that differences in wheezing between kids who had RSV and those who didn’t tend to disappear by age six or seven. By age thirteen, there’s generally no measurable difference between the two groups. Children who were younger than six months at the time of infection, those born prematurely, and those exposed to tobacco smoke or air pollution carry a higher risk of developing these longer-term breathing issues.
The Tennessee Asthma Bronchiolitis Study, which followed roughly 95,000 children, found that the greatest risk of later asthma development was in children who were about four months old during peak RSV season. This highlights how much a child’s age at the time of infection matters for long-term outcomes, not just for how severe the initial illness is.