RSV Vaccine Demonstrates High Effectiveness in Preventing Severe Respiratory Disease in Older Adults

The RSVpreF vaccine is highly effective in preventing severe respiratory syncytial virus (RSV) infections in adults aged 60 and older, according to a study published in JAMA Network Open.

On June 21, 2023, the US Advisory Committee on Immunization Practices recommended that adults aged 60 and over may receive a single dose of RSVpreF. However, vaccine effectiveness (VE) against RSV-related hospitalizations and emergency department (ED) visits has not been fully described.

“We evaluated, in a large US health care network, RSVpreF effectiveness against first occurrence of RSV-related lower respiratory tract disease [LRTD] inpatient or ED visit,” wrote Sara Tartof, PhD, MPH, Department of Research and Evaluation, Kaiser Permanente Southern California in Pasadena, and coauthors.

The researchers analyzed 7047 patients with RSV-related LRTD events, including 623 RSV-positive cases and 6424 RSV-negative controls. Among the study participants, 8.8% tested positive for RSV, and 3.2% had received the RSVpreF vaccine. Most participants (93.3%) had ≥1 comorbidity, and more than half (57.4%) were aged 75 years or older.

The adjusted VE of RSVpreF against RSV-related LRTD hospitalization or ED visits was 91% (95% CI, 59%-98%) compared with strictly defined controls and 90% (95% CI, 59%-97%) in broader analyses. Patients who received the vaccine did so a median of 61 days before their LRTD encounter. Additionally, the vaccine demonstrated an 89% VE (95% CI, 13%-99%) against severe RSV-related LRTD requiring supplemental oxygen.

Sensitivity analyses focusing on the first LRTD event for each patient yielded similar VE results. Despite high VE, vaccination rates were relatively low, with significant demographic and health-related disparities among recipients. Older adults, non-Hispanic Asian or Pacific Islander and White patients, and those with frequent outpatient visits were more likely to be vaccinated, while individuals with chronic obstructive pulmonary disease, diabetes, or peripheral vascular disease were less likely to receive the vaccine.

“Based on our study results and RSV incidence in older adults, for approximately every 250 persons vaccinated, 1 RSV-related ED or hospitalization encounter could be prevented in the first season after vaccination,” concluded the study authors.

Reference

Tartof SY, Aliabadi N, Goodwin G, et al. Estimated vaccine effectiveness for respiratory syncytial virus-related lower respiratory tract disease. JAMA Netw Open. 2024;7(12):e2450832. doi:10.1001/jamanetworkopen.2024.50832