The benefit of oseltamivir treatment in patients admitted with influenza virus infection and the design of studies addressing this issue, have been questioned extensively. Since the influenza disease burden is substantial and oseltamivir treatment is biologically plausible, we assessed the clinical benefit of oseltamivir treatment in adult patients admitted with severe seasonal influenza virus infection in daily practice.
A multicenter, retrospective cohort study was conducted to compare the effectiveness of treatment with and without oseltamivir <48 hours after admission in patients admitted with laboratory-confirmed influenza virus infection in three large hospitals in the Netherlands. Propensity score matching was used to compare clinical relevant outcome variables.
We included 390 patients, of whom 80% had comorbidity. Thirty-day mortality, as well as the composite endpoint of 30-day mortality or intensive care unit admission >48 hours after admission, were reduced by 9% (p= 0.04) and 11% (p= 0.02) respectively. Length of hospital stay and in-hospital mortality rates all showed a trend towards reduction. The median duration between symptom onset and initiation of treatment was three days.
This study supports that, in daily practice, patients admitted with influenza virus infection should be treated with oseltamivir within 48 hours of admission, even if they have complaints for more than 48 hours.

Copyright © 2020. Published by Elsevier Ltd.