{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:29:28Z","timestamp":1785414568506,"version":"3.56.0"},"reference-count":18,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T00:00:00Z","timestamp":1785110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"THE HEALTH INSTITUTES OF T\u00dcRK\u0130YE","award":["TSB-11568-VAC-COV-TUR-F3.01"],"award-info":[{"award-number":["TSB-11568-VAC-COV-TUR-F3.01"]}]},{"name":"THE HEALTH INSTITUTES OF T\u00dcRK\u0130YE","award":["TSB-VAC-COV-TUR-RF3.04"],"award-info":[{"award-number":["TSB-VAC-COV-TUR-RF3.04"]}]},{"award":["TSB-11568-VAC-COV-TUR-F3.01"],"award-info":[{"award-number":["TSB-11568-VAC-COV-TUR-F3.01"]}],"id":[{"id":"https:\/\/ror.org\/01d6ka036","id-type":"ROR","asserted-by":"publisher"}]},{"award":["TSB-VAC-COV-TUR-RF3.04"],"award-info":[{"award-number":["TSB-VAC-COV-TUR-RF3.04"]}],"id":[{"id":"https:\/\/ror.org\/01d6ka036","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background\/Objectives: COVID-19 vaccines may be given without requiring a negative test or absence of symptoms; however, this recommendation needs further safety evaluation. This study aimed to compare the adverse events following immunization (AEFI) between PCR-positive (asymptomatic\/mildly symptomatic) and PCR-negative individuals at the time of vaccination, with a secondary objective of comparing the two vaccines (TURKOVAC and CoronaVac). Methods: This descriptive study was a secondary analysis of phase III clinical trials. Individuals who were positive for SARS-CoV-2 PCR at the time of vaccination constituted the PCR(+) group and those who tested negative or became positive after the 4th day following vaccination constituted the PCR(\u2212) group. Whether participants had a history of COVID-19 was not considered. Results: Data from 5207 individuals were analyzed. AEFIs were more frequent in the PCR(+) group than PCR(\u2212) group: site pain (24.5% vs. 16.7%, p &lt; 0.001), arm pain (9.5% vs. 7.8%, p = 0.008), headache (14.8% vs. 10.0%, p &lt; 0.001), fatigue (14.5% vs. 8.9%, p &lt; 0.001), myalgia (12.3% vs. 7.5%, p &lt; 0.001), sore throat (11.9% vs. 8.1%, p &lt; 0.001), cough (7.9%; 11.1% vs. 6.9%, p &lt; 0.001). These AEFIs were more frequent in the PCR(+) group with both vaccine groups separately. The distribution of AEFIs over time followed similar patterns in PCR(+) and PCR(\u2212) individuals. Local AEFIs were slightly more common with the TURKOVAC, systemic AEFIs with the CoronaVac. Conclusions: While AEFIs were more common among PCR(+) group, they were mild, tolerable, and easily manageable. Our results support the suggestion that routine PCR testing prior to vaccination may not be warranted solely to mitigate concerns about anticipated adverse events.<\/jats:p>","DOI":"10.3390\/vaccines14080657","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T14:08:14Z","timestamp":1785161294000},"page":"657","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Adverse Events in Following Immunization with Inactivated SARS-CoV-2 Vaccines (TURKOVAC and CoronaVac) in PCR-Positive Asymptomatic or Mildly Symptomatic Individuals Compared to PCR-Negative Recipients"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1654-3232","authenticated-orcid":false,"given":"Ate\u015f","family":"Kara","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Pediatric Infectious Disease, Faculty of Medicine, Hacettepe University, Ankara 06100, T\u00fcrkiye"},{"name":"Turkiye Vaccine Institute, TUSEB Aziz Sancar Arastirma Merkezi, Ankara 06270, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u0130hsan","family":"Ate\u015f","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, University of Health Sciences Ankara City Hospital, Ankara 06800, T\u00fcrkiye"},{"name":"General Directorate of Health Services, Republic of T\u00fcrkiye Ministry of Health, Ankara 06800, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-9233-0048","authenticated-orcid":false,"given":"Sebahat","family":"Tekcan","sequence":"additional","affiliation":[{"name":"Turkiye Vaccine Institute, TUSEB Aziz Sancar Arastirma Merkezi, Ankara 06270, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Se\u00e7il","family":"Uysal","sequence":"additional","affiliation":[{"name":"Turkiye Vaccine Institute, TUSEB Aziz Sancar Arastirma Merkezi, Ankara 06270, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2978-8738","authenticated-orcid":false,"given":"Y\u00fcksel Hakan","family":"Aydo\u011fmu\u015f","sequence":"additional","affiliation":[{"name":"General Directorate of Public Health, Child and Adolescent Health Department, Ministry of Health of the Republic of T\u00fcrkiye, Ankara 06430, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mine Durusu","family":"Tanr\u0131\u00f6ver","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Hacettepe University, Ankara 06230, T\u00fcrkiye"},{"name":"Vaccine Institute, Hacettepe University, Ankara 06100, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6950-8545","authenticated-orcid":false,"given":"Aykut","family":"\u00d6zdarendeli","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Faculty of Medicine, Erciyes University, Kayseri 38039, T\u00fcrkiye"},{"name":"Vaccine Research, Development and Application Centre (ERAGEM), Erciyes University, Kayseri 38030, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6785-6896","authenticated-orcid":false,"given":"Erdogan","family":"Oz","sequence":"additional","affiliation":[{"name":"General Directorate of Public Health, Ministry of Health of the Republic of T\u00fcrkiye, Ankara 06430, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammed Emin","family":"Demirkol","sequence":"additional","affiliation":[{"name":"General Directorate of Public Health, Ministry of Health of the Republic of T\u00fcrkiye, Ankara 06430, T\u00fcrkiye"},{"name":"Department of Internal Medicine, \u0130zzet Baysal Training and Research Hospital, Abant \u0130zzet Baysal University, Bolu 14030, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,27]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2026, March 31). 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Med."}],"container-title":["Vaccines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-393X\/14\/8\/657\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T08:36:47Z","timestamp":1785314207000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-393X\/14\/8\/657"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,27]]},"references-count":18,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["vaccines14080657"],"URL":"https:\/\/doi.org\/10.3390\/vaccines14080657","relation":{},"ISSN":["2076-393X"],"issn-type":[{"value":"2076-393X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,27]]}}}