{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T03:44:51Z","timestamp":1772163891705,"version":"3.50.1"},"reference-count":16,"publisher":"BMJ","issue":"9","license":[{"start":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T00:00:00Z","timestamp":1625011200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/bmj.com\/coronavirus\/usage"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Occup Environ Med"],"published-print":{"date-parts":[[2021,9]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To assess the prevalence of SARS-CoV-2-specific IgM and IgG antibodies among workers of the three public higher education institutions of Porto, Portugal, up to July 2020.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A rapid point-of-care test for specific IgM and IgG antibodies of SARS-CoV-2 was offered to all workers (SD Biosensor STANDARD Q COVID-19 IgM\/IgG Duo and STANDARD Q COVID-19 IgM\/IgG Combo). Testing was performed and a questionnaire was completed by 4592 workers on a voluntary basis from 21 May to 31 July 2020. We computed the apparent IgM, IgG, and combined IgM or IgG prevalence, along with the true prevalence and 95% credible intervals (95%\u2009CrI) using Bayesian inference.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>We found an apparent prevalence of 3.1% for IgM, 1.0% for IgG and 3.9% for either. The estimated true prevalence was 2.0% (95% CrI 0.1% to 4.3%) for IgM, 0.6% (95% CrI 0.0% to 1.3%) for IgG, and 2.5% (95% CrI 0.1% to 5.3%) for IgM or IgG. A SARS-CoV-2 molecular diagnosis was reported by 21 (0.5%) workers; and of these, 90.5% had a reactive IgG result. Seroprevalence was higher among those reporting contacts with confirmed cases, having been quarantined, having a previous molecular negative test or having had symptoms.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The seroprevalence among workers from the three public higher education institutions of Porto after the first wave of the SARS-CoV-2 infection was similar to national estimates for the same age working population. However, the estimated true seroprevalence was approximately five times higher than the reported SARS-CoV-2 infection based on a molecular test.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/oemed-2021-107519","type":"journal-article","created":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T13:33:46Z","timestamp":1625060026000},"page":"648-653","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":8,"title":["Prevalence of SARS-CoV-2 antibodies among workers of the public higher education institutions of Porto, Portugal: a cross-sectional study"],"prefix":"10.1136","volume":"78","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9055-7491","authenticated-orcid":false,"given":"Paula","family":"Meireles","sequence":"first","affiliation":[]},{"given":"Joana","family":"Amaro","sequence":"additional","affiliation":[]},{"given":"Joana","family":"Pinto da Costa","sequence":"additional","affiliation":[]},{"given":"Mariana Mendes","family":"Lopes","sequence":"additional","affiliation":[]},{"given":"Tatiana","family":"Varandas","sequence":"additional","affiliation":[]},{"given":"Pedro","family":"Norton","sequence":"additional","affiliation":[]},{"given":"Jo\u00e3o Tiago","family":"Guimar\u00e3es","sequence":"additional","affiliation":[]},{"given":"Milton","family":"Severo","sequence":"additional","affiliation":[]},{"given":"Henrique","family":"Barros","sequence":"additional","affiliation":[]}],"member":"239","published-online":{"date-parts":[[2021,6,30]]},"reference":[{"key":"2021081710150997000_78.9.648.1","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.m3862"},{"key":"2021081710150997000_78.9.648.2","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2020.8259"},{"key":"2021081710150997000_78.9.648.3","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2020.16656"},{"key":"2021081710150997000_78.9.648.4","doi-asserted-by":"publisher","DOI":"10.1126\/science.abf4063"},{"key":"2021081710150997000_78.9.648.5","unstructured":"European centre for disease prevention and control (ECDC) . COVID-19 clusters and outbreaks in occupational settings in the EU\/EEA and the UK. Stockholm 2020 https:\/\/www.ecdc.europa.eu\/sites\/default\/files\/documents\/COVID-19-in-occupational-settings.pdf"},{"key":"2021081710150997000_78.9.648.6","doi-asserted-by":"publisher","DOI":"10.1002\/eji.202048970"},{"key":"2021081710150997000_78.9.648.7","doi-asserted-by":"crossref","DOI":"10.3390\/life10090214","article-title":"Seroprevalence of antibodies against SARS-CoV-2 among the personnel and students of the National and Kapodistrian University of Athens, Greece: a preliminary report","volume":"10","author":"Tsitsilonis","year":"2020","journal-title":"Life"},{"key":"2021081710150997000_78.9.648.8","doi-asserted-by":"publisher","DOI":"10.1136\/bmjopen-2020-046800"},{"key":"2021081710150997000_78.9.648.9","unstructured":"Find. SARS-COV-2 test performance. Available: https:\/\/www.finddx.org\/covid-19\/ab-test-perf\/ [Accessed 31 May 2021]."},{"key":"2021081710150997000_78.9.648.10","doi-asserted-by":"publisher","DOI":"10.1007\/s00038-012-0439-9"},{"key":"2021081710150997000_78.9.648.11","doi-asserted-by":"crossref","unstructured":"Devleesschauwer B , Torgerson P , Charlier J . Prevalence: tools for prevalence assessment studies. R package version 0.4.0, 2014. http:\/\/cran.r-project.org\/package=prevalence","DOI":"10.32614\/CRAN.package.prevalence"},{"key":"2021081710150997000_78.9.648.12","doi-asserted-by":"crossref","unstructured":"Kislaya I , Gon\u00e7alves P , Barreto M . Seroprevalence of SARS-CoV-2 infection in Portugal in May-July 2020: results of the first national serological survey (ISNCOVID-19). Acta M\u00e9dica Portuguesa 2021;34.doi:10.20344\/amp.15122","DOI":"10.20344\/amp.15122"},{"key":"2021081710150997000_78.9.648.13","doi-asserted-by":"publisher","DOI":"10.1016\/j.puhe.2020.06.006"},{"key":"2021081710150997000_78.9.648.14","doi-asserted-by":"crossref","first-page":"1576","DOI":"10.1001\/jamainternmed.2020.4130","article-title":"Seroprevalence of antibodies to SARS-CoV-2 in 10 sites in the United States, March 23-May 12, 2020","volume":"180","author":"Havers","year":"2020","journal-title":"JAMA Intern Med"},{"key":"2021081710150997000_78.9.648.15","doi-asserted-by":"crossref","first-page":"e02020","DOI":"10.1128\/JCM.02020-20","article-title":"Evaluation of serological SARS-CoV-2 lateral flow assays for rapid point-of-care testing","volume":"59","author":"Conklin","year":"2021","journal-title":"J Clin Microbiol"},{"key":"2021081710150997000_78.9.648.16","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-021-87289-6"}],"container-title":["Occupational and Environmental Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/oemed-2021-107519","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,9,2]],"date-time":"2024-09-02T21:00:16Z","timestamp":1725310816000},"score":1,"resource":{"primary":{"URL":"https:\/\/oem.bmj.com\/lookup\/doi\/10.1136\/oemed-2021-107519"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,30]]},"references-count":16,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2021,8,17]]},"published-print":{"date-parts":[[2021,9]]}},"alternative-id":["10.1136\/oemed-2021-107519"],"URL":"https:\/\/doi.org\/10.1136\/oemed-2021-107519","relation":{"has-preprint":[{"id-type":"doi","id":"10.1101\/2021.02.28.21252628","asserted-by":"object"}]},"ISSN":["1351-0711","1470-7926"],"issn-type":[{"value":"1351-0711","type":"print"},{"value":"1470-7926","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,30]]}}}