Respiratory syncytial virus (RSV)

Respiratory syncytial virus (RSV) is a very common virus that leads to mild, cold-like symptoms in adults and older healthy children. It can be more serious in young babies, especially those in certain high-risk groups. RSV is the most common germ causing lung and airway infections in infants and young children. Most infants have had this infection by age 2. Outbreaks of RSV infections most often begin in the fall and run into the spring. The infection can occur in people of all ages. The virus spreads through tiny droplets that go into the air when a sick person blows their nose, coughs, or sneezes.


Symptoms can vary and differ with age: they usually appear 4 to 6 days after coming into contact with the virus. Older children most often have only mild, cold-like symptoms, such as croup cough (often described as a “seal bark” cough), stuffy nose, or low-grade fever. Infants under the age 1 may experience more severe symptoms and often have the most trouble with breathing:

  • Bluish skin color due to a lack of oxygen (cyanosis) in more severe cases
  • Breathing difficulty or labored breathing
  • Nasal flaring
  • Rapid breathing (tachypnea)
  • Shortness of breath
  • Wheezing


Antibiotics cannot treat RSV. Mild infections go away without treatment. Infants and children with a severe RSV infection may be admitted to the hospital. Treatment will include:

  •  Oxygen
  • Moist (humidified) air
  • Suctioning of nasal secretions
  • Fluids through a vein (by IV)
  • A breathing machine (ventilator) may be needed.
  • Outlook (Prognosis)

More severe RSV disease may occur in the following infant patients:

  • Premature infants
  • Infants with chronic lung disease
  • Infants whose immune system does not work well
  • Infants with certain forms of heart disease

Rarely, RSV infection can cause death in infants. However, this is unlikely if the child is seen by a health care provider in the early stages of the disease.

Children who have had RSV bronchiolitis may be more likely to develop asthma.

Possible Complications

In young children, RSV can cause:

  • Bronchiolitis
  • Lung failure
  • Pneumonia

When to Contact a Medical Professional

Call your provider if breathing difficulties or other symptoms of this disorder appear. Any breathing problems in an infant are an emergency. Seek medical help right away.


To help prevent RSV infection, wash your hands often, especially before touching your baby. Make certain that other people, especially caregivers, take steps to avoid your baby contracting RSV. The following simple steps can help protect your baby from getting sick:

Insist that others wash their hands with warm water and soap before touching your baby.

Have others avoid contact with the baby if they have a cold or fever. If necessary, have them wear a mask.

Be aware that kissing the baby can spread RSV infection.

Try to keep young children away from your baby. RSV is very common among young children and easily spreads from child to child.

Do not smoke inside your house, car, or anywhere near your baby. Exposure to tobacco smoke increases the risk of RSV illness.

Parents of high-risk young infants should avoid crowds during outbreaks of RSV. Moderate-to-large outbreaks are often reported by local news sources to provide parents with an opportunity to avoid exposure.