{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:43:00Z","timestamp":1760143380950,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,2,5]],"date-time":"2024-02-05T00:00:00Z","timestamp":1707091200000},"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 aim of the rapid introduction of vaccines during the COVID-19 pandemic was a reduction in SARS-CoV-2 transmission and a less frequent occurrence of severe COVID-19 courses. Thus, we evaluated COVID-19 severity in vaccinated individuals to examine variant-specific symptom characteristics and their clinical impact on the serological immune response. Methods: A total of 185 individuals previously vaccinated against and infected with the SARS-CoV-2 Delta (B.1.617.2) or Omicron (BA.4 and BA.5) variant, were enrolled for anti-SARS-CoV-2 anti-N- and anti-RBD\/S1-Ig level detection. A structured survey regarding medical history was conducted. Results: In 99.5 percent of cases, outpatient treatment was satisfactory. Specific symptoms associated with variants included ageusia and anosmia in patients with Delta infections and throat pain in Omicron infections. Among Delta-infected individuals with specific symptoms, significantly higher levels of anti-N antibodies were observed. Conclusion: Our study identified variant-specific differences in the amount of SARS-CoV-2 antibody production and COVID-19 symptoms. Despite this, vaccinated individuals with Omicron or Delta infections generally experienced mild disease courses. Additionally, asymptomatic individuals exhibit lower anti-SARS-CoV-2 antibody levels, indicating a clinical correlation between disease-specific antibodies and distinct symptoms, particularly in the case of the Delta variant. In follow-up studies, exploring post-COVID syndrome and focusing on cognitive symptoms in the acute phase of Omicron infections is crucial as it has the potential to longitudinally impact the lives of those affected.<\/jats:p>","DOI":"10.3390\/vaccines12020163","type":"journal-article","created":{"date-parts":[[2024,2,5]],"date-time":"2024-02-05T09:31:58Z","timestamp":1707125518000},"page":"163","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Impact of Clinical Factors and SARS-CoV-2 Variants on Antibody Production in Vaccinated German Healthcare Professionals Infected Either with the Delta or the Omicron Variant"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7197-9242","authenticated-orcid":false,"given":"Catharina","family":"Gerhards","sequence":"first","affiliation":[{"name":"Institute for Clinical Chemistry, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marlene","family":"Steingass","sequence":"additional","affiliation":[{"name":"Institute for Clinical Chemistry, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandra","family":"Heininger","sequence":"additional","affiliation":[{"name":"Department of Hygiene, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3454-2081","authenticated-orcid":false,"given":"Bettina","family":"Lange","sequence":"additional","affiliation":[{"name":"Department of Hygiene, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Hetjens","sequence":"additional","affiliation":[{"name":"Department of Biomedical Informatics, Center for Preventive Medicine and Digital Health Baden-W\u00fcrttemberg, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg of University, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marlis","family":"Gerigk","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology and Hygiene, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Neumaier","sequence":"additional","affiliation":[{"name":"Institute for Clinical Chemistry, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5780-9068","authenticated-orcid":false,"given":"Osman","family":"Evliyaoglu","sequence":"additional","affiliation":[{"name":"Institute for Clinical Chemistry, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maximilian","family":"Kittel","sequence":"additional","affiliation":[{"name":"Institute for Clinical Chemistry, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"947","DOI":"10.1038\/s41562-021-01122-8","article-title":"A global database of COVID-19 vaccinations","volume":"5","author":"Mathieu","year":"2021","journal-title":"Nat. Hum. Behav."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Ssentongo, P., Ssentongo, A.E., Voleti, N., Groff, D., Sun, A., Ba, D.M., Nunez, J., Parent, L.J., Chinchilli, V.M., and Paules, C.I. (2022). SARS-CoV-2 vaccine effectiveness against infection, symptomatic and severe COVID-19: A systematic review and meta-analysis. BMC Infect. Dis., 22.","DOI":"10.1186\/s12879-022-07418-y"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"403","DOI":"10.1056\/NEJMoa2035389","article-title":"Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine","volume":"384","author":"Baden","year":"2021","journal-title":"N. Engl. J. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2439","DOI":"10.1056\/NEJMoa2027906","article-title":"Safety and Immunogenicity of Two RNA-Based COVID-19 Vaccine Candidates","volume":"383","author":"Walsh","year":"2020","journal-title":"N. Engl. J. Med."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Zhao, J., Zhao, S., Ou, J., Zhang, J., Lan, W., Guan, W., Wu, X., Yan, Y., Zhao, W., and Wu, J. (2020). COVID-19: Coronavirus Vaccine Development Updates. Front. Immunol., 11.","DOI":"10.3389\/fimmu.2020.602256"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"809244","DOI":"10.3389\/fimmu.2021.809244","article-title":"SARS-CoV-2 Variants, Vaccines, and Host Immunity","volume":"12","author":"Mistry","year":"2022","journal-title":"Front Immunol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2090","DOI":"10.1111\/all.15206","article-title":"Serological testing for SARS-CoV-2 antibodies in clinical practice: A comparative diagnostic accuracy study","volume":"77","author":"Horn","year":"2022","journal-title":"Allergy"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Gerhards, C., Thiaucourt, M., Hetjens, M., Haselmann, V., Neumaier, M., and Kittel, M. (2023). Heterologous Vector\u2014mRNA Based SARS-CoV-2 Vaccination Strategy Appears Superior to a Homologous Vector\u2014Based Vaccination Scheme in German Healthcare Workers Regarding Humoral SARS-CoV-2 Response Indicating a High Boosting Effect by mRNA Vaccines. Vaccines, 11.","DOI":"10.3390\/vaccines11030701"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"n3104","DOI":"10.1136\/bmj.n3104","article-title":"COVID-19: Omicron is causing more infections but fewer hospital admissions than delta, South African data show","volume":"375","author":"Dyer","year":"2021","journal-title":"BMJ"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1001\/jama.2021.24868","article-title":"Characteristics and Outcomes of Hospitalized Patients in South Africa During the COVID-19 Omicron Wave Compared With Previous Waves","volume":"327","author":"Maslo","year":"2022","journal-title":"JAMA"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"831","DOI":"10.7326\/M22-0308","article-title":"Comparison of Patients Infected with Delta Versus Omicron COVID-19 Variants Presenting to Paris Emergency Departments","volume":"175","author":"Bouzid","year":"2022","journal-title":"Ann. Intern. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e13762","DOI":"10.7717\/peerj.13762","article-title":"Clinical characteristics of the severe acute respiratory syndrome coronavirus 2 omicron variant compared with the delta variant: A retrospective case-control study of 318 outpatients from a single sight institute in Japan","volume":"10","author":"Suzuki","year":"2022","journal-title":"PeerJ"},{"key":"ref_13","unstructured":"(2022). Medical laboratories\u2014Requirements for quality and competence Fourth edition 2022-12. Standard No. ISO 15189."},{"key":"ref_14","unstructured":"R Core Team (2014). R: A Language and Environment for Statistical Computing, R Foundation for Statistical Computing."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.ijid.2021.04.080","article-title":"Longitudinal assessment of anti-SARS-CoV-2 antibody dynamics and clinical features following convalescence from a COVID-19 infection","volume":"107","author":"Gerhards","year":"2021","journal-title":"Int. J. Infect. Dis."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Lopez Bernal, J., Andrews, N., Gower, C., Stowe, J., Robertson, C., Tessier, E., Simmons, R., Cottrell, S., Robertson, R., and O\u2019Doherty, M. (2021). Early effectiveness of COVID-19 vaccination with BNT162b2 mRNA vaccine and ChAdOx1 adenovirus vector vaccine on symptomatic disease, hospitalisations and mortality in older adults in England. MedRxiv.","DOI":"10.1101\/2021.03.01.21252652"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Sales-Moioli, A.I.L., Galv\u00e3o-Lima, L.J., Pinto, T.K.B., Cardoso, P.H., Silva, R.D., Fernandes, F., Barbalho, I.M.P., Farias, F.L.O., Veras, N.V.R., and Souza, G.F. (2022). Effectiveness of COVID-19 Vaccination on Reduction of Hospitalizations and Deaths in Elderly Patients in Rio Grande do Norte, Brazil. Int. J. Environ. Res. Public Health, 19.","DOI":"10.3390\/ijerph192113902"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1646","DOI":"10.1016\/S0140-6736(21)00677-2","article-title":"Interim findings from first-dose mass COVID-19 vaccination roll-out and COVID-19 hospital admissions in Scotland: A national prospective cohort study","volume":"397","author":"Vasileiou","year":"2021","journal-title":"Lancet"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Porru, S., Spiteri, G., Monaco, M.G.L., Valotti, A., Carta, A., Lotti, V., Diani, E., Lippi, G., Gibellini, D., and Verlato, G. (2022). Post-Vaccination SARS-CoV-2 Infections among Health Workers at the University Hospital of Verona, Italy: A Retrospective Cohort Survey. Vaccines, 10.","DOI":"10.3390\/vaccines10020272"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2043","DOI":"10.1001\/jama.2021.19499","article-title":"Association Between mRNA Vaccination and COVID-19 Hospitalization and Disease Severity","volume":"326","author":"Tenforde","year":"2021","journal-title":"JAMA"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1303","DOI":"10.1016\/S0140-6736(22)00462-7","article-title":"Comparative analysis of the risks of hospitalisation and death associated with SARS-CoV-2 omicron (B.1.1.529) and delta (B.1.617.2) variants in England: A cohort study","volume":"399","author":"Nyberg","year":"2022","journal-title":"Lancet"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"e27","DOI":"10.1093\/cid\/ciac239","article-title":"Clinical and Virological Characteristics of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) B.1.617.2 (Delta) Variant: A Prospective Cohort Study","volume":"75","author":"Park","year":"2022","journal-title":"Clin. Infect. Dis."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Duong, B.V., Larpruenrudee, P., Fang, T., Hossain, S.I., Saha, S.C., Gu, Y., and Islam, M.S. (2022). Is the SARS-CoV-2 Omicron Variant Deadlier and More Transmissible Than Delta Variant?. Int. J. Environ. Res. Public Health, 19.","DOI":"10.3390\/ijerph19084586"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"984433","DOI":"10.3389\/fpubh.2022.984433","article-title":"Epidemiological characteristics of Omicron and Delta SARS-CoV-2 variant infection in Santiago, Chile","volume":"10","author":"Escobar","year":"2022","journal-title":"Front. Public Health"},{"key":"ref_25","first-page":"16403","article-title":"Differences between the course of SARS-CoV-2 infections in the periods of the Delta and Omicron variants dominance in Poland","volume":"133","author":"Dobrowolska","year":"2023","journal-title":"Pol. Arch. Intern. Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e2381","DOI":"10.1002\/rmv.2381","article-title":"Evolution of the SARS-CoV-2 omicron variants BA.1 to BA.5: Implications for immune escape and transmission","volume":"32","author":"Shrestha","year":"2022","journal-title":"Rev. Med. Virol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"108959","DOI":"10.1016\/j.clim.2022.108959","article-title":"Effect of monoclonal antibody therapy on the endogenous SARS-CoV-2 antibody response","volume":"236","author":"Kim","year":"2022","journal-title":"Clin. Immunol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"eaan5393","DOI":"10.1126\/sciimmunol.aan5393","article-title":"Recovery from the Middle East respiratory syndrome is associated with antibody and T cell responses","volume":"2","author":"Zhao","year":"2017","journal-title":"Sci. Immunol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1379","DOI":"10.4049\/jimmunol.167.3.1379","article-title":"Antibody-Independent Antiviral Function of Memory CD4+ T Cells In Vivo Requires Regulatory Signals from CD8+ Effector T Cells","volume":"167","author":"Zhong","year":"2001","journal-title":"J. Immunol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"100355","DOI":"10.1016\/j.xcrm.2021.100355","article-title":"Impact of SARS-CoV-2 variants on the total CD4+ and CD8+ T cell reactivity in infected or vaccinated individuals","volume":"2","author":"Tarke","year":"2021","journal-title":"Cell Rep. Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"e02376-22","DOI":"10.1128\/spectrum.02376-22","article-title":"Longevity and Neutralizing Capacity of IgG Antibodies against SARS-CoV-2 Generated by the Application of BNT162b2, AZD1222, Convidecia, Sputnik V, and CoronaVac Vaccines: A Cohort Study in the Mexican Population","volume":"11","year":"2023","journal-title":"Microbiol. Spectr."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1386","DOI":"10.1016\/j.cmi.2020.06.024","article-title":"Validation of a commercially available SARS-CoV-2 serological Immunoassay","volume":"26","author":"Meyer","year":"2020","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e01224-20","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":"Bonelli","year":"2020","journal-title":"J. Clin. Microbiol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"8540","DOI":"10.1038\/s41598-022-12479-9","article-title":"Assessment of mutations on RBD in the Spike protein of SARS-CoV-2 Alpha, Delta and Omicron variants","volume":"12","author":"Alves","year":"2022","journal-title":"Sci. Rep."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1186\/s40035-023-00357-x","article-title":"Cognitive dysfunction of patients infected with SARS-CoV-2 omicron variant in Shanghai, China","volume":"12","author":"Yuan","year":"2023","journal-title":"Transl. Neurodegener."}],"container-title":["Vaccines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-393X\/12\/2\/163\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T13:55:22Z","timestamp":1760104522000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-393X\/12\/2\/163"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,2,5]]},"references-count":35,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2024,2]]}},"alternative-id":["vaccines12020163"],"URL":"https:\/\/doi.org\/10.3390\/vaccines12020163","relation":{},"ISSN":["2076-393X"],"issn-type":[{"type":"electronic","value":"2076-393X"}],"subject":[],"published":{"date-parts":[[2024,2,5]]}}}