Clinical characteristics and outcomes in adult patients hospitalized with influenza, respiratory syncytial virus and human metapneumovirus infections

Abstract

<b>Objectives</b>: To compare the clinical characteristics and outcomes of patients hospitalized with respiratory syncytial virus (RSV), human metapneumovirus (hMPV), and influenza infections.<b>Methods</b>: This study prospectively enrolled 594 patients hospitalized with influenza-like illness (ILI) and laboratory-confirmed RSV, hMPV, or influenza infections over three consecutive influenza seasons at a tertiary hospital in China.<b>Results</b>: While certain clinical features were of value as predictors of infection type, none exhibited good predictive performance as a means of discriminating between these three infections (area under the receiver-operating characteristic curve < 0.70). After controlling for potential confounding variables, RSV infections in pneumonia patients were found to be associated with a 30-day mortality risk comparable to that of influenza patients [<i>odds ratio</i> (<i>OR</i>) 1.016, <i>95% confidence interval</i> (<i>CI</i>) 0.267-3.856, p = 0.982], whereas hMPV infection was associated with a reduced risk of mortality (<i>OR</i> 0.144, <i>95% CI</i> 0.027-0.780, p = 0.025). Among those without pneumonia, the 30-day mortality risk in patients with influenza was comparable to that in patients infected with RSV (<i>OR</i> 1.268, <i>95% CI</i> 0.172-9.355, p = 0.816) or hMPV (<i>OR</i> 1.128, <i>95% CI</i> 0.122-10.419, p = 0.916).<b>Conclusion</b>: Disease severity associated with these three types of viral infection was inconsistent when comparing patients with and without pneumonia, highlighting the importance of etiologic testing.