{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T12:16:42Z","timestamp":1782735402695,"version":"3.54.5"},"reference-count":48,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,10]],"date-time":"2022-02-10T00:00:00Z","timestamp":1644451200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: The SARS-CoV-2 vaccination campaign began on 27 December 2020 in Europe, primarily involving health workers. This study aimed to assess the SARS-CoV-2 vaccination effectiveness, as assessed by reductions in incidence, symptom severity, and further infection spreading. Methods: A retrospective cohort study was conducted on 9811 health workers operating at the Verona University Hospital, Italy, from 27 December 2020 to 3 May 2021. All health workers were offered vaccination with Comirnaty (BNT162b2, BioNTech\/Pfizer, Mainz, Germany\/New York, United States), and a health surveillance program was implemented with periodical swab testing. Vaccination status and clinical data were collected using an ad hoc semi-structured questionnaire and health surveillance charts. Results: As of 3rd of May, 82.5% of health workers had been vaccinated against SAR-CoV-2, and 177 (1.8%) had tested positive for SARS-CoV-2. Vaccination more than halved the cumulative incidence of SARS-CoV-2 infection and reduced by two-thirds the cumulative incidence of symptomatic subjects. In detail, most unvaccinated HWs were symptomatic; 50% reported fever, 45% reported ageusia\/anosmia, and nearly 20% reported dyspnea. These percentages were much lower in HWs who had been vaccinated for at least 14 days (18% for fever and anosmia, 6% for dyspnea and ageusia). Moreover, cases of vaccine breakthrough were sixfold less likely to further spread the infection than unvaccinated HWs. Conclusions: SARS-CoV-2 vaccination reduced the infection frequency among HWs, further spreading of the infection, and the presence, severity, and duration of COVID-19-related symptoms.<\/jats:p>","DOI":"10.3390\/vaccines10020272","type":"journal-article","created":{"date-parts":[[2022,2,11]],"date-time":"2022-02-11T02:40:17Z","timestamp":1644547217000},"page":"272","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Post-Vaccination SARS-CoV-2 Infections among Health Workers at the University Hospital of Verona, Italy: A Retrospective Cohort Survey"],"prefix":"10.3390","volume":"10","author":[{"given":"Stefano","family":"Porru","sequence":"first","affiliation":[{"name":"Section of Occupational Medicine, Department of Diagnostics and Public Health, University of Verona, 37134 Verona, Italy"},{"name":"Clinical Unit of Occupational Medicine, University Hospital of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8536-7095","authenticated-orcid":false,"given":"Gianluca","family":"Spiteri","sequence":"additional","affiliation":[{"name":"Clinical Unit of Occupational Medicine, University Hospital of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4951-2528","authenticated-orcid":false,"given":"Maria Grazia Lourdes","family":"Monaco","sequence":"additional","affiliation":[{"name":"Clinical Unit of Occupational Medicine, University Hospital of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Valotti","sequence":"additional","affiliation":[{"name":"Postgraduate School of Occupational Medicine, University of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3620-8765","authenticated-orcid":false,"given":"Angela","family":"Carta","sequence":"additional","affiliation":[{"name":"Section of Occupational Medicine, Department of Diagnostics and Public Health, University of Verona, 37134 Verona, Italy"},{"name":"Clinical Unit of Occupational Medicine, University Hospital of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5746-3810","authenticated-orcid":false,"given":"Virginia","family":"Lotti","sequence":"additional","affiliation":[{"name":"Section of Microbiology, Department of Diagnostics and Public Health, University of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1373-7533","authenticated-orcid":false,"given":"Erica","family":"Diani","sequence":"additional","affiliation":[{"name":"Section of Microbiology, Department of Diagnostics and Public Health, University of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9523-9054","authenticated-orcid":false,"given":"Giuseppe","family":"Lippi","sequence":"additional","affiliation":[{"name":"Section of Clinical Biochemistry, University of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Davide","family":"Gibellini","sequence":"additional","affiliation":[{"name":"Section of Microbiology, Department of Diagnostics and Public Health, University of Verona, 37134 Verona, Italy"},{"name":"Unit of Microbiology and Virology, University Hospital of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5262-8818","authenticated-orcid":false,"given":"Giuseppe","family":"Verlato","sequence":"additional","affiliation":[{"name":"Unit of Epidemiology and Medical Statistics, Department of Diagnostics and Public Health, University of Verona, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,10]]},"reference":[{"key":"ref_1","unstructured":"(2021, December 19). 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