CATEGORY: IMMUNE HEALTH
Older adults who received an RSV vaccine were far less likely to be hospitalized with an RSV lung infection than those who went unvaccinated, according to early real-world results from a large U.S. analysis. RSV — respiratory syncytial virus — is a common seasonal virus that usually causes cold-like symptoms but can turn serious in older adults.1
How the Study Worked
Researchers used a test-negative design, a common way to gauge how well a vaccine performs in everyday use: among older adults hospitalized with respiratory symptoms and tested for RSV, they compared vaccination rates between those who tested positive for the virus and those who tested negative. The analysis included 268 adults aged 60 and older who tested positive and 1,041 who tested negative, drawn from two RSV seasons between December 2023 and February 2025. The vaccine studied was the adjuvanted RSVPreF3 vaccine, one of the RSV vaccines approved for this age group.
What the Numbers Showed
Vaccinated older adults were about 82% less likely to be hospitalized for an RSV lung infection than unvaccinated older adults — a vaccine effectiveness of 82.3%. Given the study’s size, the true figure most likely falls somewhere between roughly 62% and 92%. Protection looked broadly similar across age groups and among people with other health conditions. These are early results, however, and the researchers noted that fuller analyses spanning more seasons are still to come.1
Why RSV Matters in Older Adults
For most healthy people, RSV feels like a bad cold. But in adults over 60 — especially those with heart or lung conditions — it can move into the lungs and lead to pneumonia and hospitalization. Lower respiratory tract disease simply means an infection that reaches the lower airways and lungs rather than staying in the nose and throat. That risk is why RSV vaccines were approved for this age group, and why researchers are measuring how well they hold up outside of clinical trials.
What This Does and Doesn’t Mean
A test-negative study reflects real-world use rather than a controlled experiment, and because these are early results, the estimate may shift as more data come in. It also can’t tell you what a vaccine will do for any one person. Whether an RSV vaccine makes sense for you depends on your age, your health and other factors — a decision for you and your healthcare provider to weigh together.
Key Takeaways
- In early real-world results, older adults who received the adjuvanted RSV vaccine were about 82% less likely to be hospitalized with an RSV lung infection than those who were unvaccinated.
- RSV usually causes cold-like symptoms but can become serious in adults 60 and older, particularly those with heart or lung conditions.
- These are early findings from an observational analysis, and the protection estimate may change as more seasons are studied.
- If you’re 60 or older or have a chronic condition, your healthcare provider can help you decide whether an RSV vaccine is right for you.
References
- Ku JH, Qian L, Sy LS, et al. Real-world Effectiveness of Adjuvanted RSVPreF3 Vaccine in Preventing RSV-associated Lower Respiratory Tract Disease Hospitalization in Adults ≥60 Years of Age: Early Results From a Test-negative Design Analysis. Open Forum Infectious Diseases. 2026;13(5):ofag279. link