London School of Hygiene & Tropical Medicine

A new report on the effectiveness of drugs used for the treatment and prevention of influenza states that UK hospitals must be prepared to conduct trials into the effectiveness of available antiviral drugs when the next influenza pandemic hits our shores

Published by the Academy of Medical Sciences and the Wellcome Trust,  the report looks at antiviral drugs called neuraminidase inhibitors (NAIs) - specifically oseltamivir (trade name: Tamiflu) and zanamivir (trade name: Relenza). It considers possible future treatments and defines research priorities.

Commenting on the report, Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said:

"This report is excellent and provides a dispassionate view of these drugs and their benefits which have limitations. It makes clear that in some circumstances, such as when a potentially significant fraction of key workers may be ill and not able to work, even temporarily, that a small benefit may firstly reduce the time off work but most importantly, reduce the height of a peak in the numbers absent from work on any particular day. This latter point is not made clearly in the report though it is alluded to. It can have a major economic benefit in possibly preventing a cascade of problems (beyond a "tipping point') when a major epidemic or pandemic occurs.

"The downside is that strains of flu may become rapidly resistant to it, and this seems to have happened already.

"The benefits of the drugs in the most severely ill or vulnerable are uncertain and the proposal to have good randomised trials in such groups is to be welcomed.

"The wise course may be to reserve such drugs for key workers and, if the randomised trials proposed by the report show benefits in the high risk groups, given to those at high risk and not those at low risk.

"Media-induced panics that led to widespread use of the drugs in the previous pandemic are harmful; perhaps we will have learnt a lesson. This report is absolutely rigorous in its evaluation of our current knowledge."