Outcomes Worse in Adults Hospitalized With RSV than Influenza

US adults hospitalized with respiratory syncytial virus (RSV) were more likely to have cardiopulmonary conditions, undergo longer hospital stays, and need mechanical ventilation compared with those hospitalized with influenza, according to a study published in Clinical Infectious Diseases.

“In this prospective, multisite study, we have confirmed the importance of RSV as a cause of a significant proportion of hospitalization in adults,” wrote corresponding author Emily T. Martin, PhD, of the University of Michigan School of Public Health, Ann Arbor, Michigan, and study coauthors. “We found those with underlying cardiopulmonary conditions to be a critical target for future campaigns as vaccines become available.” The study was first published online in early 2023 before US Food and Drug Administration approval of RSV vaccines for adults ages 60 years and older. The analysis included 10,311 adults hospitalized with acute respiratory illnesses at surveillance sites in Michigan, Texas, Pennsylvania, and Tennessee during the 2016–2017, 2017–2018, and 2018–2019 seasons.

Among participants, 6% tested positive for RSV, 18.8% tested positive for influenza, and 75.1% tested negative for either virus, according to the study.

Congestive heart failure and chronic obstructive pulmonary were more common among patients with RSV. In patients with RSV, rates of congestive heart failure were 37.3% and rates of chronic obstructive pulmonary disease were 47.6%, researchers reported. In patients with influenza, respective rates were 28.8% and 35.8%.

Patients with RSV had a 1.38 odds ratio for a hospital stay lasting longer than 1 week and a 1.45 odds ratio for requiring mechanical ventilation compared with patients with influenza, the study found.

“Results from our clinical outcomes analysis indicate that RSV-associated acute respiratory illness may be more severe than influenza-associated acute respiratory illness in some instances,” researchers wrote. “Fifty percent of adults with influenza detected had received an influenza vaccine, which may offer some protection against more severe influenza-associated outcomes. Additionally, increased illness severity experienced by patients with RSV may be explained in part by the presence of increased baseline cardiopulmonary diseases in these patients.”

Reference

Begley KM, Monto AS, Lamerato LE, et al. Prevalence and clinical outcomes of respiratory syncytial virus vs influenza in adults hospitalized with acute respiratory illness from a prospective multicenter study. Clin Infect Dis. 2023;76(11):1980-1988. doi:10.1093/cid/ciad031