{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T17:31:12Z","timestamp":1772213472428,"version":"3.50.1"},"reference-count":25,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2022,3,2]],"date-time":"2022-03-02T00:00:00Z","timestamp":1646179200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"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>Vaccination is our main strategy to control SARS-CoV-2 infection. Given the decrease in quantitative SARS-CoV-2 spike 1\u20132 IgG antibody titers three months after the second BNT162b2 dose, healthcare workers received a third booster six months after completing the original protocol. This study aimed to analyze the quantitative SARS-CoV-2 spike 1\u20132 IgG antibody titers and the safety of the third dose.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Material and methods<\/jats:title>\n                    <jats:p>A prospective longitudinal cohort study included healthcare workers who received a third booster six months after completing the BNT162b2 regimen. We assessed the quantitative SARS-CoV-2 spike 1\u20132 IgG antibody titers 21\u201328 days after the first and second dose, three months after the completed protocol, 1\u20137 days following the third dose, and 21\u201328 days after booster administration.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The cohort comprised 168 participants aged 41(10) years old, 67% of whom were female. The third dose was associated with an increase in quantitative antibody titers, regardless of previous SARS-CoV-2 history. In cases with a negative SARS-CoV-2 history, the median (IQR) antibody titer values increased from 379 (645.4) to 2960 (2010) AU\/ml, whereas in cases with a positive SARS-CoV-2 history, from 590 (1262) to 3090 (2080) AU\/ml (p&lt;0.001). The third dose caused a lower number of total (local and systemic) adverse events following immunization (AEFI) compared with the first two vaccines. However, in terms of specific symptoms such as fatigue, myalgia, arthralgia, fever, and adenopathy, the proportion was higher in comparison with the first and second doses (p&lt;0.05). The most common AEFI after the third BNT162b2 vaccine was pain at the injection site (n = 82, 84.5%), followed by fatigue (n = 45, 46.4%) of mild severity (n = 36, 37.1%).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The third dose applied six months after the original BNT162b2 regimen increased the quantitative SARS-CoV-2 spike 1\u20132 IgG antibody titers. The booster dose was well tolerated and caused no severe AEFI.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0263942","type":"journal-article","created":{"date-parts":[[2022,3,2]],"date-time":"2022-03-02T13:37:23Z","timestamp":1646228243000},"page":"e0263942","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":20,"title":["Effect of the third dose of BNT162b2 vaccine on quantitative SARS-CoV-2 spike 1\u20132 IgG antibody titers in healthcare personnel"],"prefix":"10.1371","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2572-4043","authenticated-orcid":true,"given":"Maria Elena","family":"Romero-Ibarguengoitia","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diego","family":"Rivera-Salinas","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yodira Guadalupe","family":"Hern\u00e1ndez-Ru\u00edz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ana Gabriela","family":"Armendariz-V\u00e1zquez","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0103-0079","authenticated-orcid":true,"given":"Arnulfo","family":"Gonz\u00e1lez-Cant\u00fa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Irene Antonieta","family":"Barco-Flores","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rosalinda","family":"Gonz\u00e1lez-Facio","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura Patricia","family":"Montelongo-Cruz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8148-8682","authenticated-orcid":true,"given":"Gerardo Francisco","family":"Del Rio-Parra","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mauricio Ren\u00e9","family":"Garza-Herrera","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jessica Andrea","family":"Leal-Mel\u00e9ndez","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miguel \u00c1ngel","family":"Sanz-S\u00e1nchez","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2022,3,2]]},"reference":[{"key":"pone.0263942.ref001","article-title":"WHO Director-General\u2019s opening remarks at the media briefing on COVID-19\u201311 March 2020 [Internet].","author":"World Health Organization","year":"2020"},{"key":"pone.0263942.ref002","article-title":"The prolongation of the health crisis and its impact on health","author":"OPS CEPAL N","year":"2021","journal-title":"the economy and social development"},{"key":"pone.0263942.ref003","doi-asserted-by":"crossref","first-page":"114222","DOI":"10.1016\/j.jviromet.2021.114222","article-title":"Evaluation of spike protein antigens for SARS-CoV-2 serology","volume":"296","author":"S Jagtap","year":"2021","journal-title":"J Virol Methods"},{"issue":"8","key":"pone.0263942.ref004","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1038\/s41577-021-00578-z","article-title":"Immunological mechanisms of vaccine-induced protection against COVID-19 in humans","volume":"21","author":"M Sadarangani","year":"2021","journal-title":"Nat Rev Immunol"},{"key":"pone.0263942.ref005","doi-asserted-by":"crossref","first-page":"100061","DOI":"10.1016\/j.puhip.2020.100061","article-title":"Pfizer: The miracle vaccine for COVID-19?","volume":"1","author":"AA Badiani","year":"2020","journal-title":"Public Health in Practice"},{"issue":"4","key":"pone.0263942.ref006","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1007\/s40265-021-01480-7","article-title":"BNT162b2 mRNA COVID-19 Vaccine: First Approval.","volume":"81","author":"YN Lamb","year":"2021","journal-title":"Drugs"},{"key":"pone.0263942.ref007","unstructured":"Food and Drug Administration. FDA Takes Key Action in Fight Against COVID-19 By Issuing Emergency Use Authorization for First COVID-19 Vaccine [Internet]. FDA. FDA; 2020 [cited 2021 Oct 8]. Available from: https:\/\/www.fda.gov\/news-events\/press-announcements\/fda-takes-key-action-fight-against-covid-19-issuing-emergency-use-authorization-first-covid-19"},{"key":"pone.0263942.ref008","author":"CDC","year":"2020"},{"key":"pone.0263942.ref009","unstructured":"Commissioner O of the. FDA Authorizes Booster Dose of Pfizer-BioNTech COVID-19 Vaccine for Certain Populations [Internet]. FDA. FDA; 2021 [cited 2021 Oct 15]. Available from: https:\/\/www.fda.gov\/news-events\/press-announcements\/fda-authorizes-booster-dose-pfizer-biontech-covid-19-vaccine-certain-populations"},{"key":"pone.0263942.ref010","author":"K Kontopoulou","year":"2021"},{"issue":"1","key":"pone.0263942.ref011","doi-asserted-by":"crossref","first-page":"1495","DOI":"10.1080\/22221751.2021.1953403","article-title":"Antibody titres decline 3-month post-vaccination with BNT162b2","volume":"10","author":"J Favresse","year":"2021","journal-title":"Emerg Microbes Infect"},{"key":"pone.0263942.ref012","article-title":"Total Anti-SARS-CoV-2 Antibodies Measured 6 Months After Pfizer-BioNTech COVID-19 Vaccination in Healthcare Workers.","author":"GL Salvagno","year":"2021","journal-title":"SSRN Journal [Internet]."},{"key":"pone.0263942.ref013","article-title":"Six-month interim analysis of ongoing immunogenicity surveillance of the mRNA-1273 vaccine in healthcare workers: A third dose is expected.","author":"M Tr\u00e9-Hardy","year":"2021","journal-title":"Journal of Infection [Internet]."},{"issue":"Suppl 1","key":"pone.0263942.ref014","doi-asserted-by":"crossref","first-page":"S31","DOI":"10.4103\/sja.SJA_543_18","article-title":"The STROBE guidelines","volume":"13","author":"S. Cuschieri","year":"2019","journal-title":"Saudi J Anaesth"},{"issue":"1","key":"pone.0263942.ref015","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1186\/s40249-021-00878-5","article-title":"Safety of SARS-CoV-2 vaccines: a systematic review and meta-analysis of randomized controlled trials.","volume":"10","author":"M Chen","year":"2021","journal-title":"Infect Dis Poverty"},{"issue":"9","key":"pone.0263942.ref016","doi-asserted-by":"crossref","first-page":"989","DOI":"10.3390\/vaccines9090989","article-title":"Safety and Efficacy of COVID-19 Vaccines: A Systematic Review and Meta-Analysis of Different Vaccines at Phase 3","volume":"9","author":"Y-J Fan","year":"2021","journal-title":"Vaccines (Basel)."},{"key":"pone.0263942.ref017","unstructured":"DiaSorin\u2019s LIAISON\u00ae SARS-CoV-2 Diagnostic Solutions [Internet]. DiaSorin. [cited 2022 Jan 3]. Available from: https:\/\/www.diasorin.com\/en\/immunodiagnostic-solutions\/clinical-areas\/infectious-diseases\/covid-19"},{"issue":"9","key":"pone.0263942.ref018","doi-asserted-by":"crossref","first-page":"e01224","DOI":"10.1128\/JCM.01224-20","article-title":"Clinical and Analytical Performance of an Automated Serological Test That Identifies S1\/S2-Neutralizing IgG in COVID-19 Patients Semiquantitatively","volume":"58","author":"F Bonelli","year":"2020","journal-title":"J Clin Microbiol"},{"key":"pone.0263942.ref019","article-title":"SARS-CoV-2 serology in 4000 health care and administrative staff across seven sites in Lombardy, Italy [Internet]","author":"MT Sandri","year":"2020"},{"issue":"12","key":"pone.0263942.ref020","doi-asserted-by":"crossref","first-page":"149154","DOI":"10.1172\/JCI149154","article-title":"One dose of SARS-CoV-2 vaccine exponentially increases antibodies in individuals who have recovered from symptomatic COVID-19","volume":"131","author":"R Levi","year":"2021","journal-title":"J Clin Invest"},{"issue":"1","key":"pone.0263942.ref021","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s43856-021-00032-0","article-title":"The antibody response to SARS-CoV-2 infection persists over at least 8 months in symptomatic patients","volume":"1","author":"R Levi","year":"2021","journal-title":"Commun Med"},{"key":"pone.0263942.ref022","article-title":"Decline of antibody titres 3 months after two doses of BNT162b2 in non-immunocompromised adults","author":"A Erice","year":"2021","journal-title":"Clinical Microbiology and Infection [Internet]"},{"key":"pone.0263942.ref023","article-title":"Third dose of the BNT162b2 vaccine in heart transplant recipients: Immunogenicity and clinical experience","author":"Y Peled","year":"2021","journal-title":"J Heart Lung Transplant"},{"key":"pone.0263942.ref024","article-title":"Protection of BNT162b2 Vaccine Booster against Covid-19 in Israel","author":"YM Bar-On","year":"2021","journal-title":"N Engl J Med"},{"key":"pone.0263942.ref025","doi-asserted-by":"crossref","first-page":"100928","DOI":"10.1016\/j.eclinm.2021.100928","article-title":"Initial observations on age, gender, BMI and hypertension in antibody responses to SARS-CoV-2 BNT162b2 vaccine","volume":"36","author":"R Pellini","year":"2021","journal-title":"EClinicalMedicine"}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0263942","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,3,2]],"date-time":"2022-03-02T13:37:42Z","timestamp":1646228262000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0263942"}},"subtitle":[],"editor":[{"given":"Mohd","family":"Adnan","sequence":"first","affiliation":[],"role":[{"role":"editor","vocabulary":"crossref"}]}],"short-title":[],"issued":{"date-parts":[[2022,3,2]]},"references-count":25,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2022,3,2]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0263942","relation":{"has-preprint":[{"id-type":"doi","id":"10.1101\/2021.10.20.21265269","asserted-by":"object"}]},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,3,2]]}}}