Respiratory syncytial virus-associated acute respiratory illness in adult non-immunocompromised patients: Outcomes, determinants of outcomes, and the effect of oral ribavirin treatment.

Background: Respiratory syncytial virus (RSV) is an increasingly common cause of respiratory illness in adult non-immunocompromised patients. Oral ribavirin was reported to improve outcomes of RSV infection in immunocompromised patients. This study aimed to determine the outcomes of non-immunocompromised patients hospitalized with RSV-associated acute respiratory illnesses (RSV-ARI), the factors independently associated with the outcomes and the effect of oral ribavirin treatment.

Methods: This retrospective, observational cohort study included 175 adults admitted to the hospital with virologically confirmed RSV-ARI during 2014-2019. Severe ARI was identified using Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) criteria for severe community-acquired pneumonia. The primary outcome was all-cause mortality within 30 days after enrollment. A multivariable Cox model was performed to identify significant predictors of mortality.

Results: Mean age was 76 ± 12.7 years. Seventy-eight (44.6%) patients met the diagnostic criteria for severe ARI. Thirty-six (20.6%) patients required invasive mechanical ventilation, and 11 (6.3%) required vasopressor. Ninety-nine (56.6%) patients received oral ribavirin treatment, and 52 (29.7%) received systemic corticosteroids. Forty-one (23.4%) patients had evidence of bacterial infection. Overall mortality was 7.4%. Mortality among patients with non-severe ARI and severe ARI was 1.04% and 15.4%, respectively. Estimated glomerular filtration rate <50 ml/min/1.73 m , severe ARI, systemic corticosteroids, and bacterial infection were independently associated with higher risk of mortality. Treatment with oral ribavirin was the only factor associated with reduced mortality (adjusted HR: 0.19, 95% CI: 0.04-0.9, P = 0.03).

Conclusion: RSV-ARI may result in significant mortality and health care utilization. Treatment with oral ribavirin may improve survival in these patients.