{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T12:13:53Z","timestamp":1780488833338,"version":"3.54.1"},"reference-count":32,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2023,5,22]],"date-time":"2023-05-22T00:00:00Z","timestamp":1684713600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006484","name":"Vifor Pharma","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100006484","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>Iron plays a key role in human immune responses; however, the influence of iron deficiency on the coronavirus disease 2019 (COVID-19) vaccine effectiveness is unclear.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Aim<\/jats:title>\n<jats:p>To assess the effectiveness of the BNT162b2 messenger RNA COVID-19 vaccine in preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19\u2013related hospitalization and death in individuals with or without iron deficiency.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Methods<\/jats:title>\n<jats:p>This large retrospective, longitudinal cohort study analyzed real-world data from the Maccabi Healthcare Services database (covering 25% of Israeli residents). Eligible adults (aged <jats:monospace>\u2265<\/jats:monospace>16 years) received a first BNT162b2 vaccine dose between December 19, 2020, and February 28, 2021, followed by a second dose as per approved vaccine label. Individuals were excluded if they had SARS-CoV-2 infection before vaccination, had hemoglobinopathy, received a cancer diagnosis since January 2020, had been treated with immunosuppressants, or were pregnant at the time of vaccination. Vaccine effectiveness was assessed in terms of incidence rates of SARS-CoV-2 infection confirmed by real-time polymerase chain reaction assay, relative risks of COVID-19\u2013related hospitalization, and mortality in individuals with iron deficiency (ferritin &lt;30 ng\/mL or transferrin saturation &lt;20%). The two-dose protection period was Days 7 to 28 after the second vaccination.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Results<\/jats:title>\n<jats:p>Data from 184,171 individuals with (mean [standard deviation; SD] age 46.2 [19.6] years; 81.2% female) versus 1,072,019 without (mean [SD] age 46.9 [18.0] years; 46.2% female) known iron deficiency were analyzed. Vaccine effectiveness in the two-dose protection period was 91.9% (95% confidence interval [CI] 83.7\u201396.0%) and 92.1% (95% CI 84.2\u201396.1%) for those with versus without iron deficiency (<jats:italic>P<\/jats:italic> = 0.96). Of patients with versus without iron deficiency, hospitalizations occurred in 28 and 19 per 100,000 during the reference period (Days 1\u20137 after the first dose), and in 19 and 7 per 100,000 during the two-dose protection period, respectively. Mortality rates were comparable between study groups: 2.2 per 100,000 (4\/181,012) in the population with iron deficiency and 1.8 per 100,000 (19\/1,055,298) in those without known iron deficiency.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec005\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Results suggest that the BNT162b2 COVID-19 vaccine is &gt;90% effective in preventing SARS-CoV-2 infection in the 3 weeks after the second vaccination, irrespective of iron-deficiency status. These findings support the use of the vaccine in populations with iron deficiency.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0285606","type":"journal-article","created":{"date-parts":[[2023,5,22]],"date-time":"2023-05-22T17:24:36Z","timestamp":1684776276000},"page":"e0285606","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":10,"title":["Iron deficiency and the effectiveness of the BNT162b2 vaccine for SARS-CoV-2 infection: A retrospective, longitudinal analysis of real-world data"],"prefix":"10.1371","volume":"18","author":[{"given":"Lilac","family":"Tene","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Avraham","family":"Karasik","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5189-8995","authenticated-orcid":true,"given":"Gabriel","family":"Chodick","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dora I. 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