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 tiny living organism. Viruses are so small they can be seen only with the most powerful microscopes. That's why they're called microorganisms (micro means very small). Other common... 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?

RSV is one of many viruses that infect the respiratory tract. Others include the cold Common Cold The common cold is a viral infection. It's one of the most common illnesses people get. Colds spread easily from person to person, especially within the first 2 days of symptoms Symptoms include... read more virus and the flu Influenza (Flu) Influenza, often called the flu, is a viral infection that affects your lungs and airways. Flu symptoms are a little bit like the common cold but are much more severe. Influenza, often called... read more virus.
When someone with RSV coughs or sneezes, a nearby person can get the virus by breathing in or touching droplets in the air that have the virus.
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?
There's is no vaccine to prevent RSV in childen. People with young children should wash their hands a lot to keep from passing on the virus.
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).