{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T02:27:24Z","timestamp":1792463244614,"version":"4.5.0"},"reference-count":31,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2024,9,19]],"date-time":"2024-09-19T00:00:00Z","timestamp":1726704000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund","doi-asserted-by":"publisher","award":["KLI 1188"],"award-info":[{"award-number":["KLI 1188"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2024,9,27]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>We aimed to evaluate the effectiveness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations in previously SARS-CoV-2\u2013infected adults in the general population of Austria during the Delta wave and with extended follow-up.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>In a nationwide retrospective cohort study, we calculated age-, sex-, and nursing home residency\u2013adjusted Cox proportional hazard ratios (HRs) of coronavirus disease 2019 (COVID-19) deaths, SARS-CoV-2 infections, and non-COVID-19 deaths from 1 October to 31 December 2021, and secondarily with extended follow-up to 30 June 2022. Relative vaccine effectiveness (rVE) is rVE = (1 \u2013 HR) \u00d7 100.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Among 494 646 previously infected adults, 169 543 had received 2 vaccine doses, 133 567 had received 1 dose, and 190 275 were unvaccinated at baseline. We recorded 17 COVID-19 deaths (6 vaccinated, 11 unvaccinated) and 8209 SARS-CoV-2 infections. Absolute risk of COVID-19 deaths was 0.003%. rVE estimates for COVID-19 deaths and reinfections exceeded 75% until the end of 2021 but decreased substantially with extended follow-up. The risk of non-COVID-19 death was lower in those vaccinated versus unvaccinated.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>First and second SARS-CoV-2 vaccine doses appear effective in the short-term, but with diminishing effectiveness over time. The extremely low COVID-19 mortality, regardless of vaccination, indicates strong protection of previous infection against COVID-19 death. Lower non-COVID-19 mortality in the vaccinated population might suggest a healthy vaccinee bias.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/ofid\/ofae547","type":"journal-article","created":{"date-parts":[[2024,9,19]],"date-time":"2024-09-19T18:54:33Z","timestamp":1726772073000},"source":"Crossref","is-referenced-by-count":11,"title":["Effectiveness of the First and Second Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine Dose: A Nationwide Cohort Study From Austria on Hybrid Versus Natural Immunity"],"prefix":"10.1093","volume":"11","author":[{"given":"Alena","family":"Chalupka","sequence":"first","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz , Graz ,","place":["Austria"]},{"name":"Institute for Surveillance and Infectious Disease Epidemiology, Austrian Agency for Health and Food Safety , Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uwe","family":"Riedmann","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz , Graz ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lukas","family":"Richter","sequence":"additional","affiliation":[{"name":"Institute for Surveillance and Infectious Disease Epidemiology, Austrian Agency for Health and Food Safety , Vienna ,","place":["Austria"]},{"name":"Institute of Statistics, Graz University of Technology , Graz ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali","family":"Chakeri","sequence":"additional","affiliation":[{"name":"Institute for Surveillance and Infectious Disease Epidemiology, Austrian Agency for Health and Food Safety , Vienna ,","place":["Austria"]},{"name":"Centre for Public Health, Medical University Vienna , Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ziad","family":"El-Khatib","sequence":"additional","affiliation":[{"name":"Institute for Surveillance and Infectious Disease Epidemiology, Austrian Agency for Health and Food Safety , Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7232-6515","authenticated-orcid":false,"given":"Martin","family":"Sprenger","sequence":"additional","affiliation":[{"name":"Institute of Social Medicine and Epidemiology, Medical University Graz , Graz ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Verena","family":"Theiler-Schwetz","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz , Graz ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Trummer","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz , Graz ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1866-7159","authenticated-orcid":false,"given":"Peter","family":"Willeit","sequence":"additional","affiliation":[{"name":"Institute of Clinical Epidemiology, Public Health, Health Economics, Medical Statistics and Informatics, Medical University of Innsbruck , Innsbruck ,","place":["Austria"]},{"name":"Department of Public Health and Primary Care, University of Cambridge , Cambridge ,","place":["United Kingdom"]},{"name":"Ignaz Semmelweis Institute, Interuniversity Institute for Infection Research , Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harald","family":"Schennach","sequence":"additional","affiliation":[{"name":"Central Institute for Blood Transfusion and Department of Immunology, Tirol Kliniken GmbH , Innsbruck ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernhard","family":"Benka","sequence":"additional","affiliation":[{"name":"Institute for Surveillance and Infectious Disease Epidemiology, Austrian Agency for Health and Food Safety , Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dirk","family":"Werber","sequence":"additional","affiliation":[{"name":"Institute for Surveillance and Infectious Disease Epidemiology, Austrian Agency for Health and Food Safety , Vienna ,","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tracy Beth","family":"H\u00f8eg","sequence":"additional","affiliation":[{"name":"Sloan School of Management, Massachusetts Institute of Technology , Cambridge, Massachusetts ,","place":["USA"]},{"name":"Department of Clinical Research, University of Southern Denmark , Odense ,","place":["Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John P A","family":"Ioannidis","sequence":"additional","affiliation":[{"name":"Departments of Medicine, Epidemiology and Population Health, Biomedical Data Science, and Statistics and Meta-Research Innovation Center at Stanford (METRICS), Stanford University , Stanford, California ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7959-1311","authenticated-orcid":false,"given":"Stefan","family":"Pilz","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz , Graz 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