RSV causes serious respiratory illness among older adults and people living with chronic medical conditions, according to previous studies. Infections can lead to emergency care, hospital stays, and death, and RSV contributes substantially to respiratory mortality in the US.

RSV vaccines for adults 60 years and older entered use in 2023. Available options include two prefusion F protein vaccines, RSVPreF3 (Arexvy; GlaxoSmithKline) and RSVpreF (Abrysvo; Pfizer), along with an mRNA-1345 vaccine (mRESVIA; Moderna).

Guidance recommends a single dose for older adults and for people at increased risk of severe RSV. Even with that recommendation, coverage remained modest by the end of the 2024–2025 season, with only 48% of US adults 75 years and older and 38% of adults aged 60 to 74 years with high-risk conditions reporting vaccination.