Design: Retrospective cohort using Medicare claims
Population: 597,430 nursing home residents aged 65 or over
Primary outcome: RSV-associated hospitalisation, death and severe outcomes
Effect: Effectiveness 73% (95% CI 65–79%) against hospitalisation; 56% (39–69%) against death

A US claims-based cohort of 597,430 Medicare beneficiaries aged 65 or over living in nursing homes compared RSV-related outcomes in vaccinated and unvaccinated residents during the first season the vaccines were available, 2023–24.

Estimated vaccine effectiveness was 73% against RSV hospitalisation (95% CI 65–79%), 56% against RSV-associated death and 59% against severe outcomes such as intensive care admission. It was 80% among long-stay residents.

These are observational estimates from billing codes, so healthier or better-cared-for residents may have been more likely to be vaccinated. Even so, they support offering RSV vaccine to frail older adults in long-term care. RSV vaccines for older adults have limited availability in India, so check local access.

Consider RSV vaccination for frail older adults, especially those in long-term care
Protection against hospitalisation was estimated at about 73% in the first season
Check local availability and cost of adult RSV vaccines before recommending one
Record vaccination status at admission for older inpatients with respiratory illness

Why it matters

RSV is an under-recognised cause of admission and death in the frailest older patients.

The statistics, in plain English

Vaccine effectiveness of 73% means the hazard of RSV hospitalisation was about a quarter of that in unvaccinated residents. Because vaccination was not randomised, part of that gap may reflect differences between residents who did and did not get the vaccine.