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RSV signs & symptoms in babies

Respiratory syncytial virus (RSV) is a common and highly contagious virus that might affects the lungs, especially in young babies. Most of the time RSV will cause a mild, cold-like illness. Even though it's the main reason babies end up in the hospital, many parents might not know its symptoms.¹

Knowing what to look for helps parents act quickly and get the right care. Getting a doctor’s help early can make a big difference in how the infection turns out.


What are the symptoms of RSV in babies and newborns?

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RSV first signs and symptoms


The first signs of RSV in babies are often similar to those of a common cold. However, the virus can progress quickly and become a serious lung infection, causing other complications, such as pneumonia or bronchiolitis.
The initial symptoms of RSV can include:
  • Congestion
  • Runny nose
  • Irritability
  • Decreased appetite
  • Fever
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Signs of severe RSV


The symptoms of RSV can worsen as the infection spreads to the lungs. The symptoms of severe RSV in babies include:
  • Short, shallow, and abnormally fast breathing
  • A wheezing cough
  • Nasal flaring
  • Reduction in feeding and drinking due to breathing difficulties
  • Unusual tiredness
  • Developing a blue tint to their lips or fingernails
  • Fever

If your baby has any of these severe symptoms, it's important to seek medical care.

How is RSV spread?

RSV is a common and highly contagious seasonal respiratory virus that spreads easily through contact with someone who is sick or infected surfaces.

It is an airborne virus usually transmitted through large droplets entering the eyes, nose, or mouth, typically through close contact or touching contaminated surfaces, such as when your baby snuggles their favorite toy.

When someone who has RSV coughs or sneezes, they can release these droplets, leading to the spread of RSV.

Learn more about how RSV spreads between newborns and babies


Frequently asked questions about RSV symptoms in babies and infants

Since most RSV cases are mild, testing is usually not required for RSV. However, depending on your baby’s medical history and the time of year, their doctor may do a nose swab or blood test to look for viruses and check white blood cell counts.

During the pediatrician's examination of your baby's lungs, the presence of RSV and bronchiolitis may be indicated by a crackling (almost crispy noise) or wheezing.

If there is an RSV infection, the cough can sound wet due to the presence of excess mucus in the airways. This can cause a rattling or gurgling sound when your baby coughs. In more severe cases, the cough may also be accompanied by difficulty breathing and wheezing, a high-pitched whistling sound that occurs when breathing.

These symptoms are indicative of a more serious infection that may require medical attention.

Right now, there is no definitive treatment routinely available for RSV. However, supportive care is available to help parents and babies through their illness. Supportive care includes:

  • Nasal suction and lubrication to provide relief from nasal congestion
  • Antipyretics (Medications to reduce fever)
  • Supplemental hydration in the event of dehydration
  • Oxygen for patients with low blood oxygen levels (hypoxia)

RSV is a highly contagious virus that can live for several hours on solid surfaces, such as tables and crib rails. The virus typically lives on soft surfaces, such as tissues and hands, for a shorter amount of time.

RSV symptoms usually have a timeline lasting an average of 7-14 days. However, some infants may experience severe illness and complications due to their developing immune systems. Most hospitalizations with RSV occur in otherwise healthy babies born at term, representing up to 75% of the hospitalizations due to RSV infections.3,5

It is important to note that all infants are at risk from RSV. RSV is a common respiratory virus that can cause mild cold-like symptoms in older children and adults, but it can be more serious in babies under one year old, especially those who are premature or have underlying health conditions.

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