Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates

The limited availability of COVID-19 vaccines has prompted extensive research on optimal vaccination strategies. Previous studies have considered various non-pharmaceutical interventions, vaccine efficacy and distribution strategies. In this work, we address the combined effects of inter-group conta...

Full description

Saved in:
Bibliographic Details
Main Authors: Iker Atienza-Diez, Gabriel Rodriguez-Maroto, Saúl Ares, Susanna Manrubia
Format: Article
Language:English
Published: The Royal Society 2024-12-01
Series:Royal Society Open Science
Subjects:
Online Access:https://royalsocietypublishing.org/doi/10.1098/rsos.240753
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1846141587329908736
author Iker Atienza-Diez
Gabriel Rodriguez-Maroto
Saúl Ares
Susanna Manrubia
author_facet Iker Atienza-Diez
Gabriel Rodriguez-Maroto
Saúl Ares
Susanna Manrubia
author_sort Iker Atienza-Diez
collection DOAJ
description The limited availability of COVID-19 vaccines has prompted extensive research on optimal vaccination strategies. Previous studies have considered various non-pharmaceutical interventions, vaccine efficacy and distribution strategies. In this work, we address the combined effects of inter-group contacts and vaccination rates under contact reduction, analysing the Spanish population’s demographic and age group contact patterns and incorporating reinfection dynamics. We conduct an exhaustive analysis, evaluating 362 880 permutations of nine age groups across six vaccination rates and two distinct, empirically quantified scenarios for social contacts. Our results show that at intermediate-to-high vaccination rates with unrestricted social contacts, optimal age-based vaccination strategies only slightly deviate from older-to-younger prioritization, yielding marginal reductions in deaths and infections. However, when significant reductions in social contacts are enforced—similar to the lockdowns in 2020—there are substantial improvements, particularly at moderate vaccination rates. These restrictions lead to a transition where infection propagation is halted, a scenario that became achievable during the pandemic with the observed vaccination rates. Our findings emphasize the importance of combining appropriate social contact reductions with vaccination to optimize age-based vaccination strategies, underscoring the complex, nonlinear dynamics involved in pandemic dynamics and the necessity for tailored context-specific interventions.
format Article
id doaj-art-59a8e93696264cd8b65a33b2a47a73ac
institution Kabale University
issn 2054-5703
language English
publishDate 2024-12-01
publisher The Royal Society
record_format Article
series Royal Society Open Science
spelling doaj-art-59a8e93696264cd8b65a33b2a47a73ac2024-12-04T05:37:59ZengThe Royal SocietyRoyal Society Open Science2054-57032024-12-01111210.1098/rsos.240753Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination ratesIker Atienza-Diez0Gabriel Rodriguez-Maroto1Saúl Ares2Susanna Manrubia3Centro Nacional de Biotecnologia (CNB), CSIC, Grupo Interdisciplinar de Sistemas Complejos (GISC), Madrid, SpainCentro Nacional de Biotecnologia (CNB), CSIC, Grupo Interdisciplinar de Sistemas Complejos (GISC), Madrid, SpainCentro Nacional de Biotecnologia (CNB), CSIC, Grupo Interdisciplinar de Sistemas Complejos (GISC), Madrid, SpainCentro Nacional de Biotecnologia (CNB), CSIC, Grupo Interdisciplinar de Sistemas Complejos (GISC), Madrid, SpainThe limited availability of COVID-19 vaccines has prompted extensive research on optimal vaccination strategies. Previous studies have considered various non-pharmaceutical interventions, vaccine efficacy and distribution strategies. In this work, we address the combined effects of inter-group contacts and vaccination rates under contact reduction, analysing the Spanish population’s demographic and age group contact patterns and incorporating reinfection dynamics. We conduct an exhaustive analysis, evaluating 362 880 permutations of nine age groups across six vaccination rates and two distinct, empirically quantified scenarios for social contacts. Our results show that at intermediate-to-high vaccination rates with unrestricted social contacts, optimal age-based vaccination strategies only slightly deviate from older-to-younger prioritization, yielding marginal reductions in deaths and infections. However, when significant reductions in social contacts are enforced—similar to the lockdowns in 2020—there are substantial improvements, particularly at moderate vaccination rates. These restrictions lead to a transition where infection propagation is halted, a scenario that became achievable during the pandemic with the observed vaccination rates. Our findings emphasize the importance of combining appropriate social contact reductions with vaccination to optimize age-based vaccination strategies, underscoring the complex, nonlinear dynamics involved in pandemic dynamics and the necessity for tailored context-specific interventions.https://royalsocietypublishing.org/doi/10.1098/rsos.240753compartmental modelcontact matrixSpanish demographic structureinhibition of epidemic propagationvaccine rollout
spellingShingle Iker Atienza-Diez
Gabriel Rodriguez-Maroto
Saúl Ares
Susanna Manrubia
Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates
Royal Society Open Science
compartmental model
contact matrix
Spanish demographic structure
inhibition of epidemic propagation
vaccine rollout
title Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates
title_full Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates
title_fullStr Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates
title_full_unstemmed Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates
title_short Optimal COVID-19 vaccine prioritization by age depends critically on inter-group contacts and vaccination rates
title_sort optimal covid 19 vaccine prioritization by age depends critically on inter group contacts and vaccination rates
topic compartmental model
contact matrix
Spanish demographic structure
inhibition of epidemic propagation
vaccine rollout
url https://royalsocietypublishing.org/doi/10.1098/rsos.240753
work_keys_str_mv AT ikeratienzadiez optimalcovid19vaccineprioritizationbyagedependscriticallyonintergroupcontactsandvaccinationrates
AT gabrielrodriguezmaroto optimalcovid19vaccineprioritizationbyagedependscriticallyonintergroupcontactsandvaccinationrates
AT saulares optimalcovid19vaccineprioritizationbyagedependscriticallyonintergroupcontactsandvaccinationrates
AT susannamanrubia optimalcovid19vaccineprioritizationbyagedependscriticallyonintergroupcontactsandvaccinationrates