A number of pharmaceutical companies have reported that they are developing human H5N1- based influenza vaccines, and some European national authorities are considering stockpilingthese 'pre-pandemic vaccines'. The rationale is that, unlike a specific 'true' pandemic vaccine, these can be made ahead of the emergence of a pandemic virus. If there is an H5N1-basedpandemic, the strategy of having a stockpiled vaccine (and possibly deploying it in advance), even if incompletely matched to the pandemic virus (perhaps giving very low protection), may prevent more infections and deaths than waiting for specific 'true' pandemic vaccines (Ferguson et al, 2006; Germann et al, 2006).