{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T18:27:43Z","timestamp":1786386463128,"version":"build-2736575974"},"reference-count":35,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T00:00:00Z","timestamp":1786320000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/"}],"funder":[{"name":"U.S. Coronavirus Aid, Relief and Economic Security Act","award":["NU2HGH000020-01-00"],"award-info":[{"award-number":["NU2HGH000020-01-00"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Frontline healthcare workers (HCWs) are among the first professionals significantly impacted by epidemics and pandemics. During the COVID-19 pandemic, HCWs had an increased risk of infection. This study aimed to determine the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among Nigerian HCWs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A cross-sectional study of 1,247 randomly selected HCWs, was conducted across seven healthcare facilities in Nigeria, from August 2022 through December 2022 (Epi week 31\u221251). This study had two parts: the knowledge, attitude, and practices (KAP) survey and the seroprevalence of SARS-CoV-2 antibodies. Healthcare cadres enrolled were nurses, laboratorians, doctors, and pharmacists who provided informed consent before enrollment. An antigen-based COVID-19 rapid diagnostic test was used to screen all HCWs at enrollment, and a SARS-CoV-2 Multi-Antigen IgG assay was used to test for the presence of SARS-CoV-2 antibodies for the seroprevalence component of the study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Findings<\/jats:title>\n                    <jats:p>\n                      A total of 1,247 HCWs were enrolled 682 (54.6%) nurses, 286 (22.9%) laboratorians, 222(18.0%) doctors, and 57(4.5%) pharmacists. The majority HCWs were males (70.5%), lived in urban areas (90.2%), had tertiary education (64.0%), and were married (81.7%). The proportion of HCWs that used drugs or smoked was 0.2%. The seropositivity of SARS-CoV-2 amongst HCWs was 98.2% of which 80.6% where due to the Nucleocapsid protein and 17.6% due to the Spike protein. Nurses were three times more likely to be seropositive for COVID-19 than laboratorians (\n                      <jats:italic>P\u2009&lt;\u20090.05<\/jats:italic>\n                      ).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Interpretation<\/jats:title>\n                    <jats:p>Our findings reveal a high prevalence of SARS-CoV-2 antibodies among HCWs, especially among nurses. At the time of this study, half of the HCWs were unvaccinated for COVID-19. As frontline HCWs remain at increased risk of occupational exposure, this study highlights the need to strengthen infection prevention strategies, particularly vaccination and infection prevention and control measures, to protect the healthcare workforce.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0354606","type":"journal-article","created":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T17:28:15Z","timestamp":1786382895000},"page":"e0354606","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["High prevalence of SARS-CoV-2 antibodies among frontline healthcare workers during the COVID-19 pandemic in three states of Nigeria from August to December 2022"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2187-8894","authenticated-orcid":true,"given":"Nnaemeka C.","family":"Iriemenam","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1986-3976","authenticated-orcid":true,"given":"Sophia","family":"Osawe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1107-035X","authenticated-orcid":true,"given":"Olusola A.","family":"Akanbi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oluwaseun","family":"Akinmulero","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ado G.","family":"Abubakar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mary","family":"Okoli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rita","family":"Okonkwo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oyewole","family":"Oyedele","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4661-0704","authenticated-orcid":true,"given":"Nifarta","family":"Andrew","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olumide","family":"Okunoye","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ugochi","family":"Ezenwelu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asmau","family":"Aminu-Alhaji","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Victor","family":"Ejeh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Edun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edward","family":"Kombu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ndidi","family":"Agala","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diana","family":"Martin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alash\u2019le","family":"Abimiku","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"McPaul I.","family":"Okoye","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"SECURE Nigeria Project Team","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,10]]},"reference":[{"key":"pone.0354606.ref001","unstructured":"WHO. 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