{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:29:35Z","timestamp":1790728175297,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,17]],"date-time":"2022-12-17T00:00:00Z","timestamp":1671235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bavarian States Ministry of Science and Arts"},{"name":"National Research Network of the University Medicine"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>SARS-CoV-2 seroprevalence was reported as substantially increased in medical personnel and decreased in smokers after the first wave in spring 2020, including in our population-based Tirschenreuth Study (TiKoCo). However, it is unclear whether these associations were limited to the early pandemic and whether the decrease in smokers was due to reduced infection or antibody response. We evaluated the association of occupation and smoking with period-specific seropositivity: for the first wave until July 2020 (baseline, BL), the low infection period in summer (follow-up 1, FU1, November 2020), and the second\/third wave (FU2, April 2021). We measured binding antibodies directed to SARS-CoV-2 nucleoprotein (N), viral spike protein (S), and neutralizing antibodies at BL, FU1, and FU2. Previous infection, vaccination, smoking, and occupation were assessed by questionnaires. The 4181 participants (3513\/3374 at FU1\/FU2) included 6.5% medical personnel and 20.4% current smokers. At all three timepoints, new seropositivity was higher in medical personnel with ORs = 1.99 (95%-CI = 1.36\u20132.93), 1.41 (0.29\u20136.80), and 3.17 (1.92\u20135.24) at BL, FU1, and FU2, respectively, and nearly halved among current smokers with ORs = 0.47 (95%-CI = 0.33\u20130.66), 0.40 (0.09\u20131.81), and 0.56 (0.33\u20130.94). Current smokers compared to never-smokers had similar antibody levels after infection or vaccination and reduced odds of a positive SARS-CoV-2 result among tested. Our data suggest that decreased seroprevalence among smokers results from fewer infections rather than reduced antibody response. The persistently higher infection risk of medical staff across infection waves, despite improved means of protection over time, underscores the burden for health care personnel.<\/jats:p>","DOI":"10.3390\/ijerph192416996","type":"journal-article","created":{"date-parts":[[2022,12,19]],"date-time":"2022-12-19T05:55:43Z","timestamp":1671429343000},"page":"16996","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Higher Infection Risk among Health Care Workers and Lower Risk among Smokers Persistent across SARS-CoV-2 Waves\u2014Longitudinal Results from the Population-Based TiKoCo Seroprevalence Study"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6582-1174","authenticated-orcid":false,"given":"Felix","family":"G\u00fcnther","sequence":"first","affiliation":[{"name":"Department of Mathematics, Stockholm University, Albanov\u00e4gen 28, 11419 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4177-4451","authenticated-orcid":false,"given":"Sebastian","family":"Einhauser","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5911-6233","authenticated-orcid":false,"given":"David","family":"Peterhoff","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"},{"name":"Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon","family":"Wiegrebe","sequence":"additional","affiliation":[{"name":"Department of Genetic Epidemiology, University of Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"},{"name":"Statistical Consulting Unit StaBLab, Department of Statistics, LMU Munich, Geschwister-Scholl-Platz 1, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hans Helmut","family":"Niller","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephanie","family":"Beileke","sequence":"additional","affiliation":[{"name":"Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philipp","family":"Steininger","sequence":"additional","affiliation":[{"name":"Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1924-1202","authenticated-orcid":false,"given":"Ralph","family":"Burkhardt","sequence":"additional","affiliation":[{"name":"Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helmut","family":"K\u00fcchenhoff","sequence":"additional","affiliation":[{"name":"Statistical Consulting Unit StaBLab, Department of Statistics, LMU Munich, Geschwister-Scholl-Platz 1, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8985-7582","authenticated-orcid":false,"given":"Olaf","family":"Gefeller","sequence":"additional","affiliation":[{"name":"Department of Medical Informatics, Biometry and Epidemiology, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg (FAU), Waldstr. 6, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7822-3835","authenticated-orcid":false,"given":"Klaus","family":"\u00dcberla","sequence":"additional","affiliation":[{"name":"Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg (FAU), Schlossgarten 4, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iris M.","family":"Heid","sequence":"additional","affiliation":[{"name":"Department of Genetic Epidemiology, University of Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ralf","family":"Wagner","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"},{"name":"Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1038\/s41467-021-21237-w","article-title":"SARS-CoV-2 antibody prevalence in England following the first peak of the pandemic","volume":"12","author":"Ward","year":"2021","journal-title":"Nat. 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