{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T15:19:24Z","timestamp":1791904764579,"version":"4.3.4"},"reference-count":38,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,11,22]],"date-time":"2024-11-22T00:00:00Z","timestamp":1732233600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>The COVID-19 pandemic has underscored the pivotal role of vaccines in mitigating the devastating impact of the virus. In Thailand, the vaccination campaign against SARS-CoV-2 began on 28 February 2021, initially prioritizing healthcare professionals before expanding into a nationwide effort on 7 June 2021. This study employs a mathematical model of COVID-19 transmission with vaccination to analyze the impact of Thailand\u2019s COVID-19 vaccination program from 1 March 2021 to 31 December 2022. We specifically assess the potential loss of lives and occurrence of severe infections across various age groups in a hypothetical scenario where vaccines were not administered. By fitting our model with officially reported COVID-19 death data, our analysis reveals that vaccination efforts prevented a total of 300,234 deaths (95% confidence interval: 295,938\u2013304,349) and averted 1.60 million severe COVID-19 infections (95% confidence interval: 1.54\u20131.65 million). Notably, the elderly population over 80 years old benefited the most from vaccination, with an estimated 84,518 lives saved, constituting 4.28% of this age group. Furthermore, individuals aged between 70 and 74 years experienced the highest reduction in severe infections, with vaccination potentially preventing 8.35% of this age bracket from developing severe COVID-19.<\/jats:p>","DOI":"10.3390\/tropicalmed9120286","type":"journal-article","created":{"date-parts":[[2024,11,25]],"date-time":"2024-11-25T06:25:19Z","timestamp":1732515919000},"page":"286","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Impact of COVID-19 Vaccination in Thailand: Averted Deaths and Severe Infections Across Age Groups"],"prefix":"10.3390","volume":"9","author":[{"given":"Chaiwat","family":"Wilasang","sequence":"first","affiliation":[{"name":"Biophysics Group, Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand"},{"name":"Center for Disease Modeling, Faculty of Science, Mahidol University, Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3349-1921","authenticated-orcid":false,"given":"Pikkanet","family":"Suttirat","sequence":"additional","affiliation":[{"name":"Biophysics Group, Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand"},{"name":"Center for Disease Modeling, Faculty of Science, Mahidol University, Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dhammika Leshan","family":"Wannigama","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Infection Control, Yamagata Prefectural Central Hospital, Yamagata 990-2292, Japan"},{"name":"Department of Microbiology, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10400, Thailand"},{"name":"Center of Excellence in Antimicrobial Resistance and Stewardship, Faculty of Medicine, Chulalongkorn University, Bangkok 10400, Thailand"},{"name":"School of Medicine, Faculty of Health and Medical Sciences, The University of Western Australia, Nedlands, Western Australia, Perth, WA 6009, Australia"},{"name":"Biofilms and Antimicrobial Resistance Consortium of ODA Receiving Countries, The University of Sheffield, Sheffield S10 2TN, UK"},{"name":"Pathogen Hunter\u2019s Research Collaborative Team, Department of Infectious Diseases and Infection Control, Yamagata Prefectural Central Hospital, Yamagata 990-2292, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3509-3433","authenticated-orcid":false,"given":"Mohan","family":"Amarasiri","sequence":"additional","affiliation":[{"name":"Environmental Water Quality Engineering Laboratory, Department of Civil and Environmental Engineer-ing, Graduate School of Engineering, Tohoku University, 6-6-06, Aramaki, Aoba-ku, Sendai 980-8579, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1368-2437","authenticated-orcid":false,"given":"Sudarat","family":"Chadsuthi","sequence":"additional","affiliation":[{"name":"Department of Physics, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0739-006X","authenticated-orcid":false,"given":"Charin","family":"Modchang","sequence":"additional","affiliation":[{"name":"Biophysics Group, Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand"},{"name":"Center for Disease Modeling, Faculty of Science, Mahidol University, Bangkok 10400, Thailand"},{"name":"Centre of Excellence in Mathematics, Ministry of Higher Education, Science, Research and Innovation, Bangkok 10400, Thailand"},{"name":"Thailand Center of Excellence in Physics, Ministry of Higher Education, Science, Research and Innovation, 328 Si Ayutthaya Road, Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1016\/S1473-3099(20)30144-4","article-title":"Early dynamics of transmission and control of COVID-19: A mathematical modelling study","volume":"20","author":"Kucharski","year":"2020","journal-title":"Lancet Infect. 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