Report 33: Modelling the allocation and impact of a COVID-19 vaccine

Comparative performance of between-population vaccine allocation strategies with applications for emerging pandemics

“…For scenarios considering heterogeneous population risk, we find that first targeting high risk individuals, either high-transmitters or those at higher risk of death after infection, results in more equal allocations between populations being optimal. Targeting high-risk individuals first, then shifting priority to lower-risk individuals is supported by previous modeling work, looking at SARS-CoV-2 vaccine allocations within a single population (Bubar et al, 2021;Chen et al, 2020;Hogan et al, 2020;Matrajt et al, 2021;Moore et al, 2021), and is in concordance with the ongoing COVAX strategy, targeting early doses to high-risk individuals, and the USA's implement which vaccinated health care workers and elderly individuals first (Gayle et al, 2020;World Health Organization, 2020). This also supports previous guidelines for 2009 H1N1 influenza where vaccines were targeted at high risk groups first, before shifting to the general population (Centers for Disease Control and Prevention, 2009).…”

“…For scenarios considering heterogeneous population risk, we find that first targeting high risk individuals, either high-transmitters or those at higher risk of death after infection, results in more equal allocations between populations being optimal. Targeting high-risk individuals first, then shifting priority to lower-risk individuals is supported by previous modeling work, looking at SARS-CoV-2 vaccine allocations within a single population, [8][9][10]36,37 and is in concordance with the ongoing COVAX strategy, targeting early doses to high-risk individuals, and the USA's implement which vaccinated health care workers and elderly individuals first. 38,39 Our modeling analyses are subject to many simplifying assumptions on population dynamics and vaccine characteristics that may not be applicable to the current pandemic.…”

“…As previous work [8][9][10] has shown, targeting specific subgroups within a given population, including older individuals, results in decreased COVID-19 morbidity and mortality. Further, previous theoretical work 11 has shown that unequal vaccine allocations might be favorable in emerging infectious disease settings, but are less optimal when incorporating realistic assumptions about population heterogeneity and contact structure.…”

“…We find that in the context of an emerging pathogen where many epidemiologic characteristics might not be known, equal vaccine allocation between populations performs optimally in most scenarios. In the specific case considering heterogeneous population risk structure, first targeting individuals at higher risk of transmission or death due to infection leads to equal resource allocation across populations.CoV-2 pandemic, previous work (Bubar et al, 2021;Hogan et al, 2020;Matrajt et al, 2021) has shown, targeting specific subgroups within a given population, including older individuals, results in decreased COVID-19 morbidity and mortality. Other papers looking at health and occupational risk factors (Buckner et al, 2021;Islam et al, 2021) found prioritizing certain occupational groups including healthcare workers, and other essential workers also decreased COVID-19 morbidity and mortality.…”

“…CoV-2 pandemic, previous work (Bubar et al, 2021;Hogan et al, 2020;Matrajt et al, 2021) has shown, targeting specific subgroups within a given population, including older individuals, results in decreased COVID-19 morbidity and mortality. Other papers looking at health and occupational risk factors (Buckner et al, 2021;Islam et al, 2021) found prioritizing certain occupational groups including healthcare workers, and other essential workers also decreased COVID-19 morbidity and mortality.…”