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Respiratory Syncytial Virus (RSV) Infection


The Manual's Editorial Staff

Reviewed/Revised Dec 2023
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What is respiratory syncytial virus (RSV) infection?

The respiratory tract is the parts of the body related to breathing (respiration). It includes the nose, windpipe, air passages in the lungs, and the lungs. RSV is a virus Overview of Viral Infections A virus is a microorganism, a tiny living organism. Other common microorganisms include bacteria. Viruses are much smaller than bacteria and can be seen only with the most powerful microscopes... read more that infects the respiratory tract.

  • RSV infections spread easily among babies and children, usually in winter and early spring

  • Nearly all children get the virus by age 4

  • RSV causes runny nose, fever, cough, and wheezing

  • Most children don't have problems, but severe infections cause trouble breathing and low oxygen levels

  • Someone can have RSV more than once, but symptoms are usually milder after the first time

What causes RSV infection?

What are the symptoms of RSV infection?

Children usually get symptoms like:

  • Runny nose

  • Fever

  • Cough and wheeze (a whistling sound when breathing)

In older children and adults, symptoms usually aren't serious. However, in babies, symptoms can be severe:

  • In babies younger than 6 months old, the first symptom may be a temporary stop in breathing (apnea)

  • Sometimes young babies have serious breathing problems with severe wheezing and low oxygen levels in their blood

How can doctors tell if my child has RSV?

Although there are many viruses that cause the same symptoms as RSV, doctors don't always need to tell them apart. But if they do, doctors test samples of mucus from the nose.

How do doctors treat RSV ?

Most children get well at home with rest and fluids. If they have trouble breathing, doctors treat them in a hospital with oxygen. Nebulizers with medicine that stops the wheezing in asthma (bronchodilators) don't help much with the wheezing in RSV infection.

How do doctors prevent RSV?

  • Wash hands

  • RSV vaccine for pregnant people

  • RSV vaccine for infants and young children

People with young children should wash their hands a lot to keep from passing on the virus.

Pregnant people who are 32 to 36 weeks pregnant immediately before or during RSV season should get an RSV vaccine. The vaccine protects your baby from getting very sick with RSV after birth.

Infants younger than 8 months old who were born during or entering their first RSV season should receive an RSV vaccine unless they were born 14 or more days after their mother got the RSV vaccine.

Babies 8 to 19 months old who are at risk of getting very sick with RSV and are entering their second RSV season should also get the RSV vaccine.

Rarely, doctors give monthly shots of a medicine (palivizumab) that can make RSV infection less severe. They use this medicine only in children who are most likely to have serious breathing problems from RSV (for example, young children who have serious heart or lung disease or those who were born very premature).

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