ATLANTA — A recent study suggested that RSV disease severity is similar to unvaccinated patients hospitalized with COVID-19 or influenza, but significantly more severe than patients hospitalized with those diseases who had been vaccinated.
That cohort study, led by national Centers for Disease Control and Prevention (CDC) researchers, involved 7,998 hospitalized adults in 20 U.S. states during February 2022 to May 2023.
“These findings suggest that before RSV vaccine introduction in the U.S., RSV disease was at least as severe as COVID-19 or influenza among unvaccinated patients and more severe than COVID-19 or influenza among vaccinated patients hospitalized with those diseases,” the authors advised.
The CDC recommended the first RSV vaccines on June 21, 2023, for adults aged 60 years and older using shared clinical decision-making. “Understanding the severity of RSV disease in adults can help guide this clinical decision-making,” according to the report in JAMA Network Open.2
The study sought to describe disease severity among adults hospitalized with RSV and compare it with the severity of COVID-19 and influenza disease by vaccination status. To do that, the research team prospectively enrolled adult participants who had been admitted to the hospital with acute respiratory illness and laboratory-confirmed RSV, SARS-CoV-2, or influenza infection at 25 hospitals in 20 states from Feb. 1, 2022, to May 31, 2023. The 7,998 participants had a median age of 67 and 50.6% were female. Data were analyzed from August to October 2023.
The researchers used multivariable logistic regression to compare the severity of RSV disease with COVID-19 and influenza severity, by COVID-19 and influenza vaccination status, for a range of clinical outcomes, including the composite of invasive mechanical ventilation (IMV) and in-hospital death.
Of the participants, 484 (6.1%) were hospitalized with RSV, 6422 (80.3%) were hospitalized with COVID-19, and 1092 (13.7%) were hospitalized with influenza.
The results indicated that, among patients with RSV, 58 (12.0%) experienced IMV or death, compared with 201 of 1,422 unvaccinated patients with COVID-19 (14.1%) and 458 of 5,000 vaccinated patients with COVID-19 (9.2%), as well as 72 of 699 unvaccinated patients with influenza (10.3%) and 20 of 393 vaccinated patients with influenza (5.1%).
“In adjusted analyzes, the odds of IMV or in-hospital death were not significantly different among patients hospitalized with RSV and unvaccinated patients hospitalized with COVID-19 (adjusted odds’ ratio [aOR], 0.82; 95% CI, 0.59-1.13; P = .22) or influenza (aOR, 1.20; 95% CI, 0.82-1.76; P = .35); however, the odds of IMV or death were significantly higher among patients hospitalized with RSV compared with vaccinated patients hospitalized with COVID-19 (aOR, 1.38; 95% CI, 1.02-1.86; P = .03) or influenza disease (aOR, 2.81; 95% CI, 1.62-4.86; P < .001),” the authors write.
The study concluded that, among adults hospitalized in this U.S. cohort during the 16 months before the first RSV vaccine recommendations, “RSV disease was less common but similar in severity compared with COVID-19 or influenza disease among unvaccinated patients and more severe than COVID-19 or influenza disease among vaccinated patients for the most serious outcomes of IMV or death.”
- Surie D, Yuengling KA, DeCuir J, et al. Severity of Respiratory Syncytial Virus vs COVID-19 and Influenza Among Hospitalized US Adults. JAMA Netw Open. 2024;7(4):e244954. doi:10.1001/jamanetworkopen.2024.4954