They looked at that, and modelled what would save the most life-years based on limited speed that the vaccine can be deployed, how well the vaccine works in stopping bad effects (i.e. death), and how well it works in stopping spread.
> JCVI has considered a number of different vaccination strategies, including those targeting transmission and those targeted at providing direct protection to persons most at risk. In order to interrupt transmission, mathematical modelling indicates that we would need to vaccinate a large proportion of the population with a vaccine which is highly effective at preventing infection (transmission). At the start of the vaccination programme, good evidence on the effects of vaccination on transmission will not be available, and vaccine availability will be more limited. The best use of available vaccine will also, in part, be dependent on the point in the pandemic the UK is at. Given the current epidemiological situation in the UK, all evidence indicates that the best option for preventing morbidity and mortality in the initial phase of the programme is to directly protect persons most at risk of morbidity and mortality.
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