The world is threatened by future pandemics. Vaccines can play a key role in preventing harm, but there will inevitably be shortages because there is no possibility of advance stockpiling. We therefore need some method of prioritising access.

This paper reports a critical interpretative review of the published literature that discusses ethical arguments used to justify how we could prioritise vaccine during an influenza pandemic. We found that the focus of the literature was often on proposing different groups as priorities (e.g. those with pre-existing health conditions, the young, the old, health care workers etc.). Different reasons were often suggested as a means of justifying such priority groupings (e.g. appeal to best overall outcomes, fairness, belonging to a vulnerable or ‘at risk’ group etc.). We suggest that much of the literature, wrongly, assumes that we are able to plan priority groups prior to the time of a particular pandemic and development of a particular vaccine. We also point out the surprising absence of various issues from the literature (e.g. how vaccines fit within overall pandemic planning, a lack of specificity about place, issues of global justice etc.).

The literature proposes a wide range of ways to prioritise vaccines, focusing on different groups and ‘principles’. Any plan to use pandemic vaccine must provide justifications for its prioritisation. The focus of this review was influenza pandemic vaccines, but lessons can be learnt for future allocations of coronavirus vaccine, if one becomes available.