{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T21:49:13Z","timestamp":1790804953620,"version":"4.1.0"},"reference-count":37,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T00:00:00Z","timestamp":1719792000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004063","name":"Knut and Alice Wallenberg Foundation","doi-asserted-by":"crossref","award":["KAW 2018.0152 and KAW 2020.0182"],"award-info":[{"award-number":["KAW 2018.0152 and KAW 2020.0182"]}],"id":[{"id":"10.13039\/501100004063","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100004063","name":"Knut and Alice Wallenberg Foundation","doi-asserted-by":"crossref","award":["KAW 2018.0152 and KAW 2020.0182"],"award-info":[{"award-number":["KAW 2018.0152 and KAW 2020.0182"]}],"id":[{"id":"10.13039\/501100004063","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Stiftelsen Bygg-G\u00f6ta f\u00f6r Vetenskaplig forskning"},{"name":"Swedish Heart Lung Foundation"},{"name":"Fonds de Recherche du Qu\u00e9bec \u2013 Sant\u00e9, the Natural Sciences and Engineering Council of Canada","award":["RGPIN-2022-04813"],"award-info":[{"award-number":["RGPIN-2022-04813"]}]},{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["PJT 173514"],"award-info":[{"award-number":["PJT 173514"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]}],"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>More than a year after recovering from COVID-19, a large proportion of individuals, many of whom work in the healthcare sector, still report olfactory dysfunctions. However, olfactory dysfunction was common already before the COVID-19 pandemic, making it necessary to also consider the existing baseline prevalence of olfactory dysfunction. To establish the adjusted prevalence of COVID-19 related olfactory dysfunction, we assessed smell function in healthcare workers who had contracted COVID\u201019 during the first wave of the pandemic using psychophysical testing.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Participants were continuously tested for SARS\u2010CoV\u20102 IgG antibodies since the beginning of the pandemic. To assess the baseline rate of olfactory dysfunction in the population and to control for the possibility of skewed recruitment of individuals with prior olfactory dysfunction, consistent SARS-CoV\u20102 IgG na\u00efve individuals were tested as a control group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Fifteen months after contracting COVID\u201019, 37% of healthcare workers demonstrated a quantitative reduction in their sense of smell, compared to only 20% of the individuals in the control group. Fifty-one percent of COVID\u201019\u2010recovered individuals reported qualitative symptoms, compared to only 5% in the control group. In a follow-up study 2.6 years after COVID-19 diagnosis, 24% of all tested recovered individuals still experienced parosmia.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In summary, 65% of healthcare workers experienced parosmia\/hyposmia 15 months after contracting COVID-19. When compared to a control group, the prevalence of olfactory dysfunction in the population increased by 41 percentage points. Parosmia symptoms were still lingering two-and-a half years later in 24% of SARS-CoV-2 infected individuals. Given the amount of time between infection and testing, it is possible that the olfactory problems may not be fully reversible in a plurality of individuals.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0306290","type":"journal-article","created":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T13:27:23Z","timestamp":1719840443000},"page":"e0306290","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":7,"title":["High prevalence of long-term olfactory disorders in healthcare workers after COVID-19: A case-control study"],"prefix":"10.1371","volume":"19","author":[{"given":"Johannes","family":"Frasnelli","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arnaud","family":"Tognetti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anja L.","family":"Winter","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Evelina","family":"Thunell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mats J.","family":"Olsson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nina","family":"Greilert","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonas K.","family":"Olofsson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastian","family":"Havervall","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlotte","family":"Th\u00e5lin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3529-8981","authenticated-orcid":true,"given":"Johan N.","family":"Lundstr\u00f6m","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,7,1]]},"reference":[{"key":"pone.0306290.ref001","doi-asserted-by":"crossref","DOI":"10.1093\/chemse\/bjaa081","article-title":"Recent Smell Loss Is the Best Predictor of COVID-19 Among Individuals With Recent Respiratory Symptoms","volume":"46","author":"RC Gerkin","year":"2021","journal-title":"Chem 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