{"doi":"10.1101/2021.09.16.21263576","title":"Impact of prior SARS-CoV-2 infection on post-vaccination SARS-CoV-2 spike IgG antibodies in a longitudinal cohort of healthcare workers","abstract":"Abstract Waning serum antibodies against SARS-CoV-2 have sparked discussions about long-term immunity and need for vaccine boosters. We examined SARS-CoV-2 spike IgG antibodies in a longitudinal cohort, comparing antibody decay in individuals who received an mRNA SARS-CoV-2 vaccine, with and without prior SARS-CoV-2 infection. We completed a longitudinal cohort of healthcare workers (HWs) between June 2020 and September 2021. HWs were included if they had a serum sample collected after SARS-CoV-2 infection and/or a serum sample collected ≥ 14 days after second dose of an mRNA SARS-CoV-2 vaccine. Linear regression models adjusting for vaccine type, age, and sex were used to compare post-vaccination antibody levels between 1) HWs with and without prior SARS-CoV-2 infection and 2) HWs with prior SARS-CoV-2 infection ≤ 90 days and > 90 days prior to first vaccine. Serum was collected from 98 HWs after SARS-CoV-2 infection and before vaccine, and 1960 HWs ≥ 14 days following second vaccine dose. Serum spike antibody levels were higher after vaccination than after natural infection. Compared to SARS-CoV-2 naïve individuals, those with prior infection maintained higher post-vaccination mean spike IgG values at 1, 3, and 6 months, after adjusting for age, sex, and vaccine type. Individuals with PCR-confirmed infection > 90 days before vaccination had higher post-vaccination antibody levels than individuals infected ≤ 90 days before vaccination. Individuals with three exposures to spike protein maintain the highest antibody levels particularly when first and second exposures were greater than 90 days apart. A booster dose provides a third exposure and may similarly induce a more durable antibody response.","journal":"medRxiv","year":2021,"id":219323,"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":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9407,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":632867,"name":"Shaoming Xiao","orcid":"0000-0002-8842-8209","position":1,"is_corresponding":false},{"id":506164,"name":"Amanda K. Debes","orcid":"0000-0003-4006-073X","position":2,"is_corresponding":false},{"id":632868,"name":"Emily Egbert","orcid":"0000-0002-9093-1778","position":3,"is_corresponding":false},{"id":108424,"name":"Patrizio Caturegli","orcid":"0000-0001-6768-6308","position":4,"is_corresponding":false},{"id":314315,"name":"Elizabeth Colantuoni","orcid":"0000-0002-0091-9434","position":5,"is_corresponding":false},{"id":250757,"name":"Aaron M. Milstone","orcid":"0000-0001-8498-8682","position":6,"is_corresponding":false},{"id":632866,"name":"Diana Zhong","orcid":"0000-0001-7487-7698","position":0,"is_corresponding":true}],"reference_count":6,"raw_metadata":null,"created_at":"2026-07-18T23:53:38.409982Z","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":[]}