Double dose oseltamivir for severe influenza—does it help?BMJ 2013; 346 doi: https://doi.org/10.1136/bmj.f3449 (Published 30 May 2013) Cite this as: BMJ 2013;346:f3449
- Ian G Barr, deputy director1,
- Aeron C Hurt, head, antiviral susceptibility1
- 1WHO Collaborating Centre for Reference and Research on Influenza, VIDRL, 10 Wreckyn St, North Melbourne, Victoria, Australia
- Correspondence to: I Barr
While it is relatively uncommon for the annually circulating seasonal influenza viruses to lead to severe influenza in humans, for certain influenza viruses, such as A(H5N1) and A(H7N9), severe influenza is a common outcome. A(H5N1) (the so called “bird flu”) has since 2003 led to 628 cases and 374 deaths,1 with the avian A(H7N9) influenza virus in China in 2013 having 131 cases and 32 deaths.2 It is not yet clear how best to treat severe influenza and whether the duration of illness can be shortened and survival improved with appropriate antiviral drug treatment. A linked paper from the South East Asian Infectious Disease Clinical Research Network (SEAICRN) (doi:10.1136/bmj.f3039) describes the effectiveness of treating adults and children (aged ≥4) with severe influenza (seasonal, pandemic, and bird flu) with either the regular dose or a double dose of the neuraminidase inhibitor oseltamivir (Tamiflu, the most commonly available anti-influenza drug).
Why is this relatively simple trial important? We have only a limited choice of drugs to treat severe influenza: the adamantanes (rimantadine and amantadine) and the neuraminidase inhibitors (oseltamivir, zanamivir, laninamivir, peramivir), although occasionally other drugs, such as ribavirin, have been used. Unfortunately, with the exception of some A(H5N1) viruses, most influenza viruses currently infecting people (including the avian A(H7N9) virus) are resistant to the adamantanes.3 This leaves the neuraminidase inhibitors, which generally have a modest therapeutic effect on non-complicated influenza, reducing symptoms by only …