{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:05:26Z","timestamp":1760234726834,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T00:00:00Z","timestamp":1623196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002261","name":"Russian Foundation for Basic Research","doi-asserted-by":"publisher","award":["20-515-55003"],"award-info":[{"award-number":["20-515-55003"]}],"id":[{"id":"10.13039\/501100002261","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["project No. 82161138003"],"award-info":[{"award-number":["project No. 82161138003"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Government contract of the Institute of Immunology and Physiology","award":["\u0410\u0410\u0410\u0410-\u041021-121012090090-9"],"award-info":[{"award-number":["\u0410\u0410\u0410\u0410-\u041021-121012090090-9"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>The present study aimed to assess antibody seropositivity prevalence among symptomatic individuals and individuals with a high risk of occupational exposure to SARS-CoV-2. Participants from Chelyabinsk (Russian Federation) who were at an increased risk of exposure to SARS-CoV-2 (high-risk group, n = 1091) and participants who either had symptoms consistent with COVID-19 or were suspected to have experienced COVID-19 in the past (symptomatic group, n = 692) were enrolled between 28 September and 30 December 2020. Blood samples were tested by enzyme-linked immunosorbent assay D-5501 SARS-Cov-2-IgG-EIA-BEST and D-5502 SARS-Cov-2-IgM-EIA-BEST (AO Vector-Best, Novosibirsk, Russia). The overall seropositivity rate was 28.33\u201328.53%. SARS-CoV-2 antibodies were detected in 17.23% (adjusted prevalence of 17.17\u201317.29%) of participants in the high-risk and 45.95% (adjusted prevalence of 45.91\u201346.24%) in the symptomatic group. Higher IgG and IgM titers were observed in women compared to men, as well as in participants in the symptomatic group compared to those in the high-risk group. The results indicate that the seroprevalence among residents in several Russian regions is low (28.38%) and inadequate to provide herd immunity. The lower seroprevalence among participants in the high-risk group may be attributed to the enforcement of healthcare protocols and the use of adequate personal protective equipment.<\/jats:p>","DOI":"10.3390\/vaccines9060627","type":"journal-article","created":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T14:16:04Z","timestamp":1623248164000},"page":"627","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Seroprevalence of SARS-CoV-2 Antibodies in Symptomatic Individuals Is Higher than in Persons Who Are at Increased Risk Exposure: The Results of the Single-Center, Prospective, Cross-Sectional Study"],"prefix":"10.3390","volume":"9","author":[{"given":"Alexandr","family":"Zurochka","sequence":"first","affiliation":[{"name":"School of Medical Biology, South Ural State University, 454080 Chelyabinsk, Russia"},{"name":"Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Dobrinina","sequence":"additional","affiliation":[{"name":"Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vladimir","family":"Zurochka","sequence":"additional","affiliation":[{"name":"School of Medical Biology, South Ural State University, 454080 Chelyabinsk, Russia"},{"name":"Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Desheng","family":"Hu","sequence":"additional","affiliation":[{"name":"Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandr","family":"Solovyev","sequence":"additional","affiliation":[{"name":"NPO National Medical Association for the Development of the Expert Activities in the Field of Laboratory Diagnostics \u201cMedLabExpert\u201d, 117042 Moscow, Russia"},{"name":"LCC GMK MEDMA, 620102 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liana","family":"Ryabova","sequence":"additional","affiliation":[{"name":"Department of Propedeutics of Internal Diseases, South Ural State Medical University, 454092 Chelyabinsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9402-051X","authenticated-orcid":false,"given":"Igor","family":"Kritsky","sequence":"additional","affiliation":[{"name":"Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049 Ekaterinburg, Russia"},{"name":"Institute of Natural Sciences and Mathematics, Ural Federal University Named after the First President of Russia, 620026 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roman","family":"Ibragimov","sequence":"additional","affiliation":[{"name":"Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049 Ekaterinburg, Russia"},{"name":"Institute of Natural Sciences and Mathematics, Ural Federal University Named after the First President of Russia, 620026 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexey","family":"Sarapultsev","sequence":"additional","affiliation":[{"name":"School of Medical Biology, South Ural State University, 454080 Chelyabinsk, Russia"},{"name":"Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Science, 620049 Ekaterinburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,9]]},"reference":[{"key":"ref_1","unstructured":"(2021, May 31). 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