Rationing safe and effective Covid-19 vaccines: allocating to states proportionate to population may undermine commitments to mitigating health disparities

A central goal in the National Academies of Science, Engineering and Medicine’s (NASEM) framework for equitable COVID-19 vaccine allocation is to mitigate existing inequities, particularly those affecting economically worse-off racial and ethnic minorities. 1,2,3 The Advisory Committee on Immunization Practice (ACIP) likewise notes that equity demands to “reduce, rather than increase, health disparities in each phase of vaccine distribution”. A crucial question in this regard is how vaccines should be distributed to states. The default is to allocate proportionate to population size. However, this approach risks increasing scarcity for worse-off populations in states where they represent above-average shares. To avoid lower odds of receiving a vaccine for worse-off groups, more vaccines could be given to states with larger shares of worse-off populations, and fewer to ones with smaller shares. We show here the consequences of allocating by these two different approaches.