{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T19:37:08Z","timestamp":1773517028398,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,19]],"date-time":"2021-10-19T00:00:00Z","timestamp":1634601600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>COVID-19, which is caused by SARS-CoV-2, is an occupational health risk, especially for healthcare employees due to their higher exposure and consequently higher risk of symptomatic and asymptomatic infections. This study was designed to determine the longitudinal seroprevalence of specific immunoglobulin-G (IgG) antibodies in employees in a hospital setting. All employees in a secondary care hospital, including healthcare and non-healthcare workers, were invited to participate in this single-center study. After an initial screening, a 6-month follow-up was carried out, which included serological examination for SARS-CoV-2 IgG antibodies and a questionnaire for self-reported symptoms, self-perception, and thoughts about local and national hygiene and pandemic plans. The seroprevalence of SARS-CoV-2 IgG antibodies was 0.74% among 406 hospital employees (0.75% in healthcare workers, 0.72% in non-healthcare workers), initially recruited in April 2020, in their follow-up blood specimens in October 2020. In this study, 30.54% of the participants reported using the official German coronavirus mobile application and the majority were content with the local and national rules in relation to coronavirus-related restrictions. At the 6-month follow-up, the 0.74% seroprevalence was below the reported seroprevalence of 1.35% in the general German population. The prevalence in healthcare workers in direct patient care compared with that in workers without direct patient contact did not differ significantly. Further follow-up to monitor the seroprevalence in the high-risk healthcare sector during the ongoing global pandemic is essential.<\/jats:p>","DOI":"10.3390\/ijerph182010972","type":"journal-article","created":{"date-parts":[[2021,10,20]],"date-time":"2021-10-20T03:01:13Z","timestamp":1634698873000},"page":"10972","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Half-Year Longitudinal Seroprevalence of SARS-CoV-2-Antibodies and Rule Compliance in German Hospital Employees"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3562-6575","authenticated-orcid":false,"given":"Jonas","family":"Herzberg","sequence":"first","affiliation":[{"name":"Department of Surgery, Krankenhaus Reinbek St. Adolf-Stift, Hamburger Strasse 41, 21465 Reinbek, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tanja","family":"Vollmer","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universit\u00e4tsklinik der Ruhr-Universit\u00e4t Bochum, Georgstrasse 11, 32545 Bad Oeynhausen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bastian","family":"Fischer","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universit\u00e4tsklinik der Ruhr-Universit\u00e4t Bochum, Georgstrasse 11, 32545 Bad Oeynhausen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8808-6667","authenticated-orcid":false,"given":"Heiko","family":"Becher","sequence":"additional","affiliation":[{"name":"Institute of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ann-Kristin","family":"Becker","sequence":"additional","affiliation":[{"name":"Asklepios Klinik Harburg Abteilung f\u00fcr Psychiatrie und Psychotherapie, Ei\u00dfendorfer Pferdeweg 52, 21075 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hany","family":"Sahly","sequence":"additional","affiliation":[{"name":"Labor Lademannbogen MVZ Hamburg, Lademannbogen 61, 22339 Hamburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Human","family":"Honarpisheh","sequence":"additional","affiliation":[{"name":"Department of Surgery, Krankenhaus Reinbek St. Adolf-Stift, Hamburger Strasse 41, 21465 Reinbek, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Salman Yousuf","family":"Guraya","sequence":"additional","affiliation":[{"name":"Clinical Sciences Department, College of Medicine, University of Sharjah, P.O. 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