Vaccinated Older Adults Were Hospitalized With RSV Far Less Often

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

268 RSV Positive Adults Compared With 1,041 Negative

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. Only 7 of the 268 adults who tested positive for RSV had been vaccinated, compared with 143 of the 1,041 who tested negative.¹ The vaccine studied was the adjuvanted RSVPreF3 vaccine, one of the RSV vaccines approved for this age group.

Vaccine Effectiveness of 82.3% Against Hospitalization

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

In Adults Over 60, RSV Can Reach the Lungs

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.

Early Test-Negative Results May Shift With More Data

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.

A Larger Study of 6,958 Adults Found 58%

A review pooling 36 real-world studies of RSV vaccination in older adults found protection against hospitalization in the same broad range as this result.² But a larger US study of 6,958 hospitalized adults 60 and older over the same two seasons put effectiveness at about 58%, with weaker protection in people with heart or blood-vessel disease (56%) than without (80%), and in those who were immunocompromised, meaning weakened immune defenses.³

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 covering two RSV seasons, and the protection estimate may change as more seasons are studied.

References

1. 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
2. Trusinska D, Lee B, Ferdous S, et al. Real-world evidence on RSV vaccine uptake, effectiveness, and safety in older adults: a systematic review and meta-analysis. The Lancet Regional Health–Europe. 2026;64:101623. link.
3. Surie D, Self WH, Yuengling KA, et al. RSV vaccine effectiveness against hospitalization among US adults aged 60 years or older during 2 seasons. JAMA. 2025;334(16):1442–1442. link.