The RSV vaccine for adults is a one-dose shot that protects against severe lung infections caused by respiratory syncytial virus, a common respiratory illness that sends tens of thousands of older adults to the hospital each year. Three RSV vaccines are currently approved in the United States: Arexvy (GSK), Abrysvo (Pfizer), and mResvia (Moderna). The CDC recommends the vaccine for all adults 75 and older, and for adults 50 to 74 who have certain chronic health conditions.
Who Should Get the RSV Vaccine
The broadest recommendation covers everyone 75 and older, regardless of health status. If you’re between 50 and 74, the CDC recommends vaccination if you have an increased risk of severe RSV illness. Two of the three vaccines, Abrysvo and mResvia, are also FDA-approved for adults as young as 18 who are at increased risk.
The conditions that qualify someone in the 50-to-74 age range include:
- Chronic heart disease such as heart failure or coronary artery disease (high blood pressure alone doesn’t count)
- Chronic lung disease including COPD, emphysema, asthma, interstitial lung disease, or cystic fibrosis
- Kidney disease requiring dialysis or other renal replacement
- Complicated diabetes that has caused kidney damage, nerve damage, or eye damage, or that requires insulin
- Neurologic or neuromuscular conditions that weaken the ability to cough or breathe effectively, such as ALS or muscular dystrophy
- Chronic liver disease such as cirrhosis
- Blood disorders like sickle cell disease
- Severe obesity with a BMI of 40 or higher
- Weakened immune system from disease or medication
- Residence in a nursing home
Your provider can also recommend the vaccine if other factors raise your risk, including general frailty or living in a remote area where getting to a hospital quickly would be difficult.
How Well the Vaccine Works
In clinical trials, the vaccines showed strong short-term protection that faded over time. Moderna’s mResvia, for example, was about 79% effective at preventing RSV-related lower respiratory tract disease in the first few months after vaccination. By 19 months, that figure dropped to roughly 47%. The other two vaccines showed a similar pattern of robust early protection followed by a gradual decline.
That decline doesn’t mean the vaccine stops being useful. Even at the lower level, it still cuts the risk of severe RSV lung disease roughly in half. RSV tends to cause the most damage in a single bad season, so the initial spike in protection matters. The current recommendation is for a single dose; guidance on whether a booster is needed may evolve as more long-term data becomes available.
Why RSV Matters for Older Adults
RSV is often thought of as a childhood illness, but it poses a serious threat to older adults and people with chronic disease. In adults, RSV can trigger pneumonia, worsen existing COPD or asthma, and push heart failure into a dangerous flare. Adults 75 and older and those with weakened immune systems face the highest risk of hospitalization and death.
Many adults who get RSV assume they just have a bad cold. In most healthy younger adults, that’s essentially true. But in someone with compromised lungs or a weakened heart, the virus can overwhelm the lower airways and lead to respiratory failure. The vaccine targets this progression specifically, training the immune system to fight the virus before it reaches the lungs.
Side Effects and Safety
The most common side effects are what you’d expect from any vaccine: soreness at the injection site, fatigue, headache, and muscle aches. These typically resolve within a day or two.
There is a rare but notable safety signal. The FDA has added a warning to the prescribing information for Abrysvo and Arexvy regarding Guillain-Barré syndrome (GBS), a condition where the immune system attacks nerve cells and causes muscle weakness. Postmarketing data suggest an increased risk of GBS in the 42 days after vaccination. The estimated excess risk is about 7 to 9 additional cases per million doses in people 65 and older. That’s a very small absolute number, and the FDA has stated the evidence is not sufficient to prove the vaccines directly cause GBS. Still, the warning is there, and it’s worth discussing with your provider if you have a history of GBS or are weighing your personal risk.
Cost and Insurance Coverage
If you have Medicare Part D, the RSV vaccine is covered at no cost to you. There’s no copay or deductible for vaccines recommended by the CDC’s advisory committee. Medicare Advantage plans that include drug coverage work the same way. Most private insurers also cover recommended vaccines without cost-sharing, though it’s worth confirming with your plan before scheduling.
When to Get Vaccinated
RSV circulates most heavily during the fall and winter, following a seasonal pattern similar to flu. The ideal time to get vaccinated is late summer or early fall, before RSV activity picks up. This timing also lines up with flu and COVID-19 booster season, and many people choose to get their RSV shot at the same appointment. Your provider can help you decide whether to space the shots out or get them together based on your health situation.
Unlike the flu vaccine, the RSV vaccine is currently recommended as a single dose rather than an annual shot. If you’ve already received one dose in a prior season, you do not need another one at this time.