{"doi":"10.3390/covid5080129","title":"Insights Gained from the Immune Response and Screening of Healthcare Workers After COVID-19 Vaccination","abstract":"Background: COVID-19 vaccination has been a key tool in protecting healthcare workers (HCWs), but breakthrough infections have occurred. The durability of vaccine-induced immunity and its impact on HCWs remain critical for public health strategies. Methods: In this small cohort study (n = 32), we assessed antibody levels and breakthrough infection rates in HCWs over 12 months post-vaccination, providing insights for booster strategies and infection control. A cohort of 32 HCWs was screened for SARS-CoV-2 infection using weekly self-administered swabs and blood samples collected at baseline, 6 months, and 12 months. SARS-CoV-2 antibodies (IgG, IgM) targeting spike proteins and nucleocapsids were analyzed using a multi-antigen serology panel. Pooled nucleic acid testing was employed for infection detection. Results: Nine participants showed breakthrough infections, with nucleocapsid antibodies indicating prior infection. Eight of these cases occurred after the third vaccine dose during the Omicron-dominant period. Anti-spike antibody levels declined significantly in participants without prior infection, while those with breakthrough infections exhibited increased levels. The half-life of S1 and S1 receptor-binding domain (RDB) vaccine-induced antibodies was 144 and 166 days, respectively, which aligns with CDC data. These findings provide valuable insights for determining the optimal timing of booster doses. Conclusions: Our findings highlight the waning antibody levels over time and the occurrence of breakthrough infections. Although based on a small sample, these data support the need for ongoing monitoring and timely boosters.","journal":"COVID","year":2025,"id":572252,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9527,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1397755,"name":"Jennifer Huynh","orcid":"0009-0006-9624-4975","position":1,"is_corresponding":false},{"id":1478887,"name":"Bryan V. Pham","orcid":null,"position":2,"is_corresponding":false},{"id":243562,"name":"Magali Porrachia","orcid":null,"position":3,"is_corresponding":false},{"id":243561,"name":"Caroline Ignacio","orcid":null,"position":4,"is_corresponding":false},{"id":1478447,"name":"Sasi Mudumba","orcid":"0000-0003-0582-1521","position":5,"is_corresponding":false},{"id":1478888,"name":"Cristina N. Kuizon","orcid":null,"position":6,"is_corresponding":false},{"id":240305,"name":"Sara Gianella","orcid":"0000-0002-9927-0849","position":7,"is_corresponding":false},{"id":240304,"name":"Antoine Chaillon","orcid":"0000-0001-9490-3857","position":8,"is_corresponding":false},{"id":36878,"name":"Davey M. Smith","orcid":"0000-0003-3603-1733","position":0,"is_corresponding":true}],"reference_count":32,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T02:57:23.653298Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}