{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T15:23:04Z","timestamp":1767626584162,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T00:00:00Z","timestamp":1620777600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["2020.10172.BD","692_61376255"],"award-info":[{"award-number":["2020.10172.BD","692_61376255"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mathematics"],"abstract":"<jats:p>In this paper, we present an age-structured SEIR model that uses contact patterns to reflect the physical distance measures implemented in Portugal to control the COVID-19 pandemic. By using these matrices and proper estimates for the parameters in the model, we were able to ascertain the impact of mitigation strategies employed in the past. Results show that the March 2020 lockdown had an impact on disease transmission, bringing the effective reproduction number (R(t)) below 1. We estimate that there was an increase in the transmission after the initial lift of the measures on 6 May 2020 that resulted in a second wave that was curbed by the October and November measures. December 2020 saw an increase in the transmission reaching an R(t) = 1.45 in early January 2021. Simulations indicate that the lockdown imposed on the 15 January 2021 might reduce the intensive care unit (ICU) demand to below 200 cases in early April if it lasts at least 2 months. As it stands, the model was capable of projecting the number of individuals in each infection phase for each age group and moment in time.<\/jats:p>","DOI":"10.3390\/math9101084","type":"journal-article","created":{"date-parts":[[2021,5,12]],"date-time":"2021-05-12T22:46:14Z","timestamp":1620859574000},"page":"1084","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Mathematical Modelling of the Impact of Non-Pharmacological Strategies to Control the COVID-19 Epidemic in Portugal"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6569-7772","authenticated-orcid":false,"given":"Constantino","family":"Caetano","sequence":"first","affiliation":[{"name":"Instituto Nacional de Sa\u00fade Doutor Ricardo Jorge, 1649-016 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5004-6101","authenticated-orcid":false,"given":"Maria Lu\u00edsa","family":"Morgado","sequence":"additional","affiliation":[{"name":"Center for Computational and Stochastic Mathematics, Instituto Superior T\u00e9cnico, University of Lisbon, 1049-001 Lisbon, Portugal"},{"name":"Department of Mathematics, University of Tr\u00e1s-os-Montes e Alto Douro, UTAD, 5001-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6766-4336","authenticated-orcid":false,"given":"Paula","family":"Patr\u00edcio","sequence":"additional","affiliation":[{"name":"Center for Mathematics and Applications (CMA), FCT NOVA and Department of Mathematics, FCT NOVA, Quinta da Torre, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9937-6144","authenticated-orcid":false,"given":"Jo\u00e3o F.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Department of Mathematics, University of Tr\u00e1s-os-Montes e Alto Douro, UTAD, 5001-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6230-7209","authenticated-orcid":false,"given":"Baltazar","family":"Nunes","sequence":"additional","affiliation":[{"name":"Instituto Nacional de Sa\u00fade Doutor Ricardo Jorge, 1649-016 Lisbon, Portugal"},{"name":"Centro de Investiga\u00e7\u00e3o em Sa\u00fade P\u00fablica, Escola Nacional de Sa\u00fade P\u00fablica, Universidade NOVA de Lisboa, 1600-560 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"689","DOI":"10.1016\/S0140-6736(20)30260-9","article-title":"Nowcasting and forecasting the potential domestic and international spread of the 2019-nCoV outbreak originating in Wuhan, China: A modelling study","volume":"395","author":"Wu","year":"2020","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Maugeri, A., Barchitta, M., Battiato, S., and Agodi, A. 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