Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece.
The results of a simulation-based evaluation of several policies for vaccine rollout are reported, particularly focusing on the effects of delaying the second dose of two-dose vaccines. In the presence of limited vaccine supply, the specific policy choice is a pressing issue for several countries wo...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2022-01-01
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| Series: | PLoS ONE |
| Online Access: | https://doi.org/10.1371/journal.pone.0263977 |
| _version_ | 1811296420860264448 |
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| author | Petros Barmpounakis Nikolaos Demiris Ioannis Kontoyiannis George N Pavlakis Vana Sypsa |
| author_facet | Petros Barmpounakis Nikolaos Demiris Ioannis Kontoyiannis George N Pavlakis Vana Sypsa |
| author_sort | Petros Barmpounakis |
| collection | DOAJ |
| description | The results of a simulation-based evaluation of several policies for vaccine rollout are reported, particularly focusing on the effects of delaying the second dose of two-dose vaccines. In the presence of limited vaccine supply, the specific policy choice is a pressing issue for several countries worldwide, and the adopted course of action will affect the extension or easing of non-pharmaceutical interventions in the next months. We employ a suitably generalised, age-structure, stochastic SEIR (Susceptible → Exposed → Infectious → Removed) epidemic model that can accommodate quantitative descriptions of the major effects resulting from distinct vaccination strategies. The different rates of social contacts among distinct age-groups (as well as some other model parameters) are informed by a recent survey conducted in Greece, but the conclusions are much more widely applicable. The results are summarised and evaluated in terms of the total number of deaths and infections as well as life years lost. The optimal strategy is found to be one based on fully vaccinating the elderly/at risk as quickly as possible, while extending the time-interval between the two vaccine doses to 12 weeks for all individuals below 75 years old, in agreement with epidemic theory which suggests targeting a combination of susceptibility and infectivity. This policy, which is similar to the approaches adopted in the UK and in Canada, is found to be effective in reducing deaths and life years lost in the period while vaccination is still being carried out. |
| first_indexed | 2024-04-13T05:49:12Z |
| format | Article |
| id | doaj.art-18905ac6a82e4f8dae24be6aa5463592 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-13T05:49:12Z |
| publishDate | 2022-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-18905ac6a82e4f8dae24be6aa54635922022-12-22T02:59:51ZengPublic Library of Science (PLoS)PLoS ONE1932-62032022-01-01174e026397710.1371/journal.pone.0263977Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece.Petros BarmpounakisNikolaos DemirisIoannis KontoyiannisGeorge N PavlakisVana SypsaThe results of a simulation-based evaluation of several policies for vaccine rollout are reported, particularly focusing on the effects of delaying the second dose of two-dose vaccines. In the presence of limited vaccine supply, the specific policy choice is a pressing issue for several countries worldwide, and the adopted course of action will affect the extension or easing of non-pharmaceutical interventions in the next months. We employ a suitably generalised, age-structure, stochastic SEIR (Susceptible → Exposed → Infectious → Removed) epidemic model that can accommodate quantitative descriptions of the major effects resulting from distinct vaccination strategies. The different rates of social contacts among distinct age-groups (as well as some other model parameters) are informed by a recent survey conducted in Greece, but the conclusions are much more widely applicable. The results are summarised and evaluated in terms of the total number of deaths and infections as well as life years lost. The optimal strategy is found to be one based on fully vaccinating the elderly/at risk as quickly as possible, while extending the time-interval between the two vaccine doses to 12 weeks for all individuals below 75 years old, in agreement with epidemic theory which suggests targeting a combination of susceptibility and infectivity. This policy, which is similar to the approaches adopted in the UK and in Canada, is found to be effective in reducing deaths and life years lost in the period while vaccination is still being carried out.https://doi.org/10.1371/journal.pone.0263977 |
| spellingShingle | Petros Barmpounakis Nikolaos Demiris Ioannis Kontoyiannis George N Pavlakis Vana Sypsa Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece. PLoS ONE |
| title | Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece. |
| title_full | Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece. |
| title_fullStr | Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece. |
| title_full_unstemmed | Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece. |
| title_short | Evaluating the effects of second-dose vaccine-delay policies in European countries: A simulation study based on data from Greece. |
| title_sort | evaluating the effects of second dose vaccine delay policies in european countries a simulation study based on data from greece |
| url | https://doi.org/10.1371/journal.pone.0263977 |
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