On Dec. 16, 2024, JAMA Network Open published a study demonstrating respiratory syncytial virus (RSV) vaccine effectiveness in adults 60 and older of 90% for both RSV–related hospitalization and emergency department (ED) visits. The study provides real-world VE data based on the 2023-24 RSV season and outcomes seen among adults aged 60 years or older with hospitalizations or ED visits at Kaiser Permanente of Southern California from November 24, 2023, to April 9, 2024.

All participants had respiratory swabs collected and tested for RSV. Though previous trials have shown high VE, most trialed adults were 75 years or older. RSVpreF (Abrysvo) vaccine receipt during the first RSV season after licensure, and 21 or more days before the illness event was the main assessment. Abrysvo was approved for use in the United States in June 2023 as a single-dose vaccine meant to protect older adults from severe RSV infections. 

RSV causes a significant burden of disease for US adults. Each year approximately 160,000 RSV-related acute respiratory infection hospitalizations and 120,000 ED visits are related to the virus.