Can RSV Turn Into Pneumonia?

Respiratory syncytial virus (RSV) is a respiratory virus that’s most active during cold and flu season. It’s known for causing the common cold in children and adults. But it can cause more serious illness, too — especially in babies, young children, and older adults.  

RSV is best known for causing bronchiolitis, a serious lung infection, in young children. But RSV can cause pneumonia, too. Here’s how you can tell whether RSV has turned into pneumonia and what to do next if you think your symptoms are getting worse. 

Does RSV cause pneumonia?

Yes. RSV can cause pneumonia. In fact, it’s one of the most common causes of pneumonia in young children.

Pneumonia is an infection of the air sacs that make up the lungs. Different viruses, bacteria and fungi can cause pneumonia. These bugs cause the air sacs to become inflamed and fill with fluid and pus. This causes symptoms like:

• Cough

• Phlegm

• Trouble breathing

• Shortness of breath

• Chest pain

• Fever

Pneumonia can lead to serious illness, especially in younger children, older adults, and those with weakened immune systems. Some people need treatment in the hospital for pneumonia. And RSV-associated pneumonia is no exception. Thousands of adults are hospitalized every year because of serious RSV illness. And up to 3% of all children who develop RSV need to be hospitalized, too. 

How does RSV turn into pneumonia?

RSV illness doesn’t usually start out as pneumonia. It almost always starts off as an upper respiratory tract infection, like the common cold. 

RSV spreads easily from person to person through respiratory droplets. If someone with RSV coughs or sneezes, you can pick up RSV by breathing in these RSV-containing droplets.

Once it’s inside the body, RSV attaches to cells inside the nose and throat (the upper respiratory tract). From there, it triggers an inflammatory response and starts to make copies of itself. This leads to symptoms of upper respiratory infections like:

• Cough

• Sore throat

• Runny nose

• Fatigue

• Sinus pressure and headache

The immune system is usually able to fight off the RSV virus within 7 to 10 days, allowing people to recover from their illness. Most of the time, the immune system stops RSV before it has a chance to spread beyond the upper respiratory tract. 

But sometimes, RSV is able to invade the lower respiratory tract. The lower respiratory tract includes the lungs’ airways and air sacs. When RSV infects the lower respiratory tract, it can cause pneumonia and other lower respiratory tract illnesses, like bronchitis and bronchiolitis. 

What are the symptoms of pneumonia from RSV?

Since RSV attacks the upper respiratory tract first, people who develop RSV pneumonia usually start off with symptoms of a common cold. Then after a few days, they develop more serious symptoms like: 

• Fever

• Severe cough

• Difficulty breathing

• Rapid breathing

• Wheezing

Young children, babies, and older adults may have trouble eating or drinking because of pneumonia symptoms. This puts them at risk for developing dehydration in addition to pneumonia. 

Who is at risk for developing pneumonia from RSV?

Children and adults who have certain medical conditions are at higher risk for developing RSV pneumonia. People who have a higher risk of having pneumonia caused by RSV include: 

• Babies and toddlers who were born prematurely

• Babies younger than 6 months and adults older than 65 years 

• Young children with a history of chronic heart or lung conditions

• Adults with a history of heart failure, asthma, diabetes, or chronic obstructive pulmonary disease (COPD)

• Children or adults with a weakened immune system or a history of organ transplants

• Children or adults with neuromuscular conditions like cerebral palsy or muscular dystrophy

If you or a loved one are at risk for developing RSV pneumonia, keep track of symptoms. If you notice a change, or rapid worsening of symptoms, it could be a sign that RSV has spread to the lungs. 

What should you do if you think you have pneumonia and RSV?

See your primary care provider right away if you think you have RSV pneumonia. You may need treatments for RSV like oxygen, inhaled medications, or even intravenous medications to help you fight off the infection. 

Don’t wait for your symptoms to get worse if you’re at high risk for developing RSV pneumonia. Mild symptoms can progress quickly, so it’s best to seek care early on. Your healthcare professional may want to adjust any medications you’re already taking and test you for other respiratory illnesses like COVID-19 or influenza. 

Can you stop RSV from turning into pneumonia?

Yes. While there’s no cure for RSV, there are things you can do to lower your chance of developing RSV pneumonia. 

Getting an RSV vaccine can keep you from getting sick with RSV. RSV vaccines also greatly lower your risk of developing severe RSV illness, like RSV pneumonia, if you do get sick with RSV.  

RSV vaccines for adults older than 60 years

The FDA has approved two RSV vaccines for adults older than 60 years: Arexvy and Abrysvo. These vaccines help your immune system make antibodies against the RSV-F protein that the virus uses to get inside your cells. 

Researchers found that one dose of each vaccine was over 80% effective in preventing pneumonia in healthy people. 

Abrysvo is also approved for people who are 32 to 36 weeks pregnant. The vaccine offers protection to the unborn baby. Researchers have found vaccination reduces the risk of RSV hospitalization by 57% in a baby’s first 6 months of life.  

RSV vaccines for infants and children

There are also injections to prevent RSV illness in children younger than 19 months. But they’re not technically vaccines. They’re actually monoclonal antibodies that imitate the body’s natural immune system.   

These protective antibody products include:

• Nirsevimab (Beyfortus): A single dose of Beyfortus is recommended for all infants younger than 8 months during their first RSV season. In studies, Beyfortus lowered the risk of serious RSV illness by 80%. Children with certain medical conditions may be eligible for a dose during their second RSV season. 

• Palivizumab (Synagis): Synagis is only approved for certain infants who are at high risk for serious RSV illness. Protection from Synagis doesn’t last very long so children need monthly doses during their first RSV season. 

Why trust our experts?

Written by:

Brian Clista, MD

Dr. Clista is a board-certified pediatrician who works in private practice in Pittsburgh, Pennsylvania. He previously served as a National Health Service Corporation Scholar in the inner city of Pittsburgh for 11 years.

Edited by:

Patricia Pinto-Garcia, MD, MPH

Patricia Pinto-Garcia, MD, MPH, is a medical editor at GoodRx. She is a licensed, board-certified pediatrician with more than a decade of experience in academic medicine.

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