It used to be that influenza was the main respiratory virus that got a lot of attention during the wintertime.
But now there’s another one that’s become known for its potential to cause serious illness in older adults: respiratory syncytial virus (RSV).
Unlike COVID-19, which only appeared in the U.S. in 2020, RSV has actually been around for decades. However, until recently, many doctors treated it mostly as a pediatric concern, because RSV is a top cause of hospitalization in young children.
This is now changing. RSV is actually similar to the flu, or even COVID, in that it’s older adults (along with young children) who are most likely to get dangerously ill.
Hence, this is a respiratory virus that all older adults should know about.
Furthermore, in 2023, the FDA approved the first RSV vaccines for people aged 60 or older. As of 2024, there are three RSV vaccines licensed for use in the US, for adults ages 60 and older.
So in this article, I’ll explain what is RSV, and what older adults and families should know about it.
What is RSV (Respiratory Syncytial Virus)?
RSV is a virus in the Orthopneumovirus family. In most healthy people, it infects the “upper respiratory tract,” which means the nose, throat, and upper airways. This basically causes cold symptoms (although some people may have no noticeable symptoms), and most people recover within 1-2 weeks.
However, in people who are very young, very old, or medically vulnerable, RSV can worsen and cause more severe illness, such as pneumonia or even death.
Adults with lung conditions, such as asthma or chronic obstructive pulmonary disease (COPD), are also at higher risk for severe illness from RSV.
RSV is a top cause of hospitalization among young children. However, RSV also often affects older adults: a study published in 2017 found that among older adults, RSV was likely the cause of a serious respiratory infection in 12% of cases. And among older adults hospitalized with RSV, the mortality rate was 6-8%.
The CDC has estimated that “every year RSV causes approximately 58,000โ80,000 hospitalizations and 100โ300 deaths in children ages <5 years, as well as 60,000โ160,000 hospitalizations and 6,000โ10,000 deaths among adults ages 65 years and older.”
How is RSV transmitted?
RSV is thought to spread the way many colds are: through a combination of droplets, direct contact, and airborne transmission.
So you could catch RSV by being near someone who is coughing or sneezing. Or you could catch it by touching a person or surface infected with RSV, and then touching your own nose, eyes, or mouth.
Per the CDC, people with RSV are usually contagious for 3-8 days; people with weakened immune systems may be able to transmit the virus for even longer.
Outbreaks of RSV can definitely happen in nursing homes, and in other settings where frailer older adults congregate. (There are surely outbreaks among younger adults as well, but these don’t get diagnosed as RSV because they are “colds” for most people.)
RSV is usually seasonal, with RSV transmission highest in the fall and winter.
You can view current RSV activity via the CDC’s National Respiratory Virus Surveillance page.
What are the symptoms of RSV?
In adults, RSV causes cold symptoms, such as nasal congestion, cough, and sometimes low-grade fever.
It can also cause some wheezing and shortness of breath. This is most common in older adults who have a pre-existing lung condition, such as asthma or COPD, but can happen to anyone.
RSV can also cause a worsening of a chronic heart condition such as heart failure.
In some more vulnerable adults, RSV can worsen into a pneumonia. The symptoms of pneumonia include cough, shortness of breath, and weakness. Fever is also common (although it is harder to generate fever as the immune system gets older).
How is RSV diagnosed and treated?
RSV can be detected in the emergency room or the hospital with a special PCR test. (There is also a rapid test available, but does not work as well in adults as it does in young children.)
How RSV is diagnosed and treated depends on whether the person’s symptoms are mild or not.
Mild RSV
Most of the time, when an adult gets RSV, the symptoms are mild. This means the person has cold symptoms and might feel blah, but they do NOT have RSV danger signs such as:
- Shortness of breath
- Wheezing
- Significant weakness
When it comes to mild respiratory illnesses, it can be nearly impossible to tell whether the person is sick with RSV, a cold, COVID, or a mild case of influenza.
Unless the person seems to be sick with COVID (in which case treatment with Paxlovid can be considered, especially for older adults), the treatment for all other mild respiratory illnesses is “supportive care,” meaning rest and over-the-counter medications to help with congestion and cough, if needed.
(You can check for COVID using an over-the-counter rapid test; if it’s still negative after 3-4 days of symptoms, you’re probably not dealing with COVID.)
Severe RSV
If an older person is experiencing more significant symptoms, such as shortness of breath, wheezing, or weakness, then it’s important to get a medical evaluation to check for pneumonia or other signs of severe illness.
In the emergency room, doctors will often test for COVID, influenza and RSV.
At this time, there is no particular pharmacologic treatment available for RSV, meaning there is no drug or medication that is specifically designed to treat RSV in older adults.
When older adults are hospitalized with RSV, the treatment usually includes IV hydration plus treatments to stabilize breathing.
What to know about the RSV vaccine
As of 2024, the CDC has decided to recommend a single dose of any FDA-licensed RSV vaccine for all adults ages 75 and older, and for adults ages 60-74 at increased risk of severe RSV.
For 2024-2025, there are three RSV vaccines available. Two were used in 2023 (and showed good effectiveness in real-world studies). The third vaccine (mResvia, from Moderna) was just approved in 2024.
The details about the three RSV vaccines
They are:
- Arexvy (from GlaxoSmithKline), which is made of recombinant RSV F protein antigen (based on the RSV-A subtype), combined with an adjuvant (the same adjuvant used in the shingles vaccine Shingrix)
- Abrysvo (from Pfizer), which is made of recombinant RSV F protein antigen (based on RSV-A and RSV-B subtypes)
- mResvia (from Moderna), which is an mRNA vaccine that gets the body to make RSV F antigen
The CDC’s Advisory Committee on Immunization Practices (ACIP) reviewed trial data and real-world efficacy data in the summer of 2024, and concluded that these vaccines provide good protection against severe RSV. (You can view the slides presented here.)
The vaccine was deemed to be overall safe. You can learn more about the efficacy and safety data for these vaccines on the CDC’s RSV Vaccination page for health providers.
Note: the RSV vaccines available for older adults are NOT the same as the preventive RSV monoclonal antibody treatment (nirsevimab) approved in 2023 for young children.
Which older adults should get the RSV vaccine?
The CDC now recommends that all adults aged 75 or older get a single dose of RSV vaccine.
RSV vaccination is also recommended for adults ages 60-74, who are at high risk for severe RSV.
In general, the older adults who are most likely to benefit from RSV vaccination are the ones at higher risk of severe RSV. This includes older adults who:
- have chronic lung conditions or chronic heart conditions
- are immunocompromised
- live in nursing homes or assisted living
- have other serious chronic medical conditions, such as liver disease, advanced kidney disease, or problems with their blood counts
To get vaccinated, or to discuss whether RSV vaccination might be good for you, be sure to talk to your health provider.
Is the RSV an annual vaccine?
No, RSV does not need to be given annually, so for now the recommendation is just a single dose of vaccine.
That said: research data is showing that the effectiveness of RSV does weaken with time. So the CDC is trying to determine what might be a good revaccination interval. It’s certainly possible that within the next few years, the CDC will recommend revaccination for RSV.
In Summary
RSV has been around for a long time, and has probably had more of an impact on frail older adults than many people realize.
Especially now that RSV vaccines have become available for older adults, it’s good for us all to be more aware of RSV in older adults.
Be sure to talk to your doctor about RSV vaccination if you — or if your older loved one — are age 75 or older. You can also ask about it if you have a lung condition or are otherwise at higher risk for severe RSV.
Otherwise, the good news is that you can reduce transmission of RSV by taking the same precautions that help reduce exposure to COVID, influenza, and other respiratory viruses:
- Keep indoor spaces well-ventilated (and advocate for cleaner indoor air standards in public places!
- Steer clear of people with cold symptoms
- Wash your hands often
- Consider a KN95 or N95 mask in crowded indoor environments or when on public transit
If an older person seems significantly unwell from a respiratory illness, make sure to bring them into urgent care, or even the emergency room if they are quite short of breath or very weak. It’s important to check and see if it’s the flu, COVID, or RSV. (Or it could be a bacterial pneumonia, or something else!)
Hopefully this winter, we’ll experience less respiratory illnesses than we have these past few winters.
Judy Capp says
Thank you Dr. Kernisan for all your needed information, right on time. I really appreciate it. Judy
Nicole Didyk, MD says
You are most welcome and I’m glad the information was timely for you!
Omar says
Thanks, this is a very valuable information.
Nicole Didyk, MD says
I’m so glad you find the article valuable! Thanks for taking the time to leave a comment.
Beth Krackov, Ph.D. says
Thanks for this timely info about RSV, and the link to the CDC’s RSV surveillance page. Just chatting
with friends about whether or not to take the RSV vaccine. Now I can make a more informed
decision.
Nicole Didyk, MD says
I’m glad the article was helpful. Please share it with your friends if you think they might be interested.
charlie anstey says
Hi, I just returned from my pharmacy and asked them about the RSV vaccine. They told me that it is $300. for a single dose and not covered by my insurance. I will not be getting it.
Nicole Didyk, MD says
I’m sorry to hear that the cost isn’t covered by your insurance. If you’re in a hgih risk group for RSV illness, your pharmacist might be able to advise you about any special programs that could subsidize the vaccine for you.
Teresa Young says
Thank you so much for your informative newsletters. I have learned a lot from you over the past few months. I cannot always read your newsletters immediately and have created a folder under your name to which I can easily go to and catch up at a later time/date.
I appreciate the time/effort you go to to research and write your articles. Thank you again, Teresa
Nicole Didyk, MD says
Thank you, Teresa! It means so much that you took the time to leave a comment and I’m really impressed that you have a “Dr. Kernisan” folder! Great idea.