{"doi":"10.1093/ofid/ofac563","title":"Evaluation of Severe Acute Respiratory Syndrome Coronavirus 2 Nucleocapsid Antigen in the Blood as a Diagnostic Test for Infection and Infectious Viral Shedding","abstract":"Abstract Background SARS-CoV-2 nucleocapsid antigen can be detected in plasma, but little is known about its performance as a diagnostic test for acute SARS-CoV-2 infection or infectious viral shedding among nonhospitalized individuals. Methods We used data generated from anterior nasal and blood samples collected in a longitudinal household cohort of SARS-CoV-2 cases and contacts. Participants were classified as true positives if polymerase chain reaction (PCR) positive for SARS-CoV-2 and as true negatives if PCR negative and seronegative. Infectious viral shedding was determined by the cytopathic effect from viral culture. Stratified by 7 days after symptom onset, we constructed receiver operating characteristic (ROC) curves to describe optimized accuracy (Youden index), optimized sensitivity, and specificity. Results Of 80 participants, 58 (73%) were true positives while 22 (27%) were true negatives. Using the manufacturer's cutoff of 1.25 pg/mL for evaluating infection, sensitivity was higher from 0 to 7 days (77.6% [95% confidence interval {CI}, 64%–88.2%]) than from 8 to 14 days (43.2% [95% CI, 31.1%–54.5%]) after symptom onset; specificity was unchanged at 100% (95% CI, 88.1%–100%). This test had higher sensitivity (100% [95% CI, 88.4%–100%]) and lower specificity (65% [95% CI, 40.8%–84.6%]) for infectious viral shedding as compared with infection, particularly within the first week of symptom onset. Although the presence of N-antigen correlated with infectious viral shedding (r = 0.63; P < .01), sensitivity still declined over time. Additional cutoffs from ROC curves were identified to optimize sensitivity and specificity. Conclusions We found that this SARS-CoV-2 N-antigen test was highly sensitive for detecting early but not late infectious viral shedding, making it a viable screening test for community-dwelling individuals to inform isolation practices.","journal":"Open Forum Infectious Diseases","year":2022,"id":278177,"datarank":0.31191623125197543,"base_score":2.0794415416798357,"endowment":2.0794415416798357,"self_citation_contribution":0.31191623125197543,"citation_network_contribution":0.0,"self_endowment_contribution":0.31191623125197543,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":7,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.5176,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":636924,"name":"Michelle C. Davidson","orcid":"0000-0002-5518-9774","position":1,"is_corresponding":false},{"id":636926,"name":"Khamal Anglin","orcid":"0000-0002-1801-5345","position":2,"is_corresponding":false},{"id":619680,"name":"Scott Lu","orcid":null,"position":3,"is_corresponding":false},{"id":618496,"name":"Sarah A. Goldberg","orcid":"0000-0002-8642-1468","position":4,"is_corresponding":false},{"id":239642,"name":"Miguel Garcia-Knight","orcid":"0000-0001-9556-3719","position":5,"is_corresponding":false},{"id":239643,"name":"Michel Tassetto","orcid":"0000-0001-5666-8796","position":6,"is_corresponding":false},{"id":858329,"name":"Amethyst Zhang","orcid":null,"position":7,"is_corresponding":false},{"id":636927,"name":"Mariela Romero","orcid":"0009-0009-0251-1342","position":8,"is_corresponding":false},{"id":637656,"name":"Jesus Pineda-Ramirez","orcid":null,"position":9,"is_corresponding":false},{"id":858331,"name":"Ruth Diaz-Sanchez","orcid":null,"position":10,"is_corresponding":false},{"id":637653,"name":"Paulina Rugart","orcid":null,"position":11,"is_corresponding":false},{"id":401605,"name":"Jessica Y. Chen","orcid":"0000-0002-4833-6756","position":12,"is_corresponding":false},{"id":636929,"name":"Kevin C. Donohue","orcid":"0000-0002-4237-5957","position":13,"is_corresponding":false},{"id":858330,"name":"Joshua R. Shak","orcid":null,"position":14,"is_corresponding":false},{"id":618498,"name":"Ahmed Chenna","orcid":"0000-0001-6201-2494","position":15,"is_corresponding":false},{"id":618500,"name":"John Winslow","orcid":"0000-0003-2701-2493","position":16,"is_corresponding":false},{"id":461185,"name":"Christos J. Petropoulos","orcid":"0000-0001-5496-8090","position":17,"is_corresponding":false},{"id":618499,"name":"Brandon C. Yee","orcid":"0000-0003-4649-7975","position":18,"is_corresponding":false},{"id":439991,"name":"Jeremy J. Lambert","orcid":"0000-0002-4204-3602","position":19,"is_corresponding":false},{"id":316641,"name":"David V. Glidden","orcid":"0000-0001-5888-1419","position":20,"is_corresponding":false},{"id":314414,"name":"George W. Rutherford","orcid":"0000-0002-0707-8287","position":21,"is_corresponding":false},{"id":71691,"name":"Steven G. Deeks","orcid":"0000-0001-6371-747X","position":22,"is_corresponding":false},{"id":228705,"name":"Michael J. Peluso","orcid":"0000-0003-0585-6230","position":23,"is_corresponding":false},{"id":239647,"name":"Raul Andino","orcid":"0000-0001-5503-9349","position":24,"is_corresponding":false},{"id":239684,"name":"Jeffrey N. Martin","orcid":"0000-0002-9773-3256","position":25,"is_corresponding":false},{"id":252180,"name":"J. Daniel Kelly","orcid":"0000-0002-7616-0321","position":26,"is_corresponding":false},{"id":637647,"name":"Sujata Mathur","orcid":null,"position":0,"is_corresponding":true}],"reference_count":40,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T00:28:43.133347Z","pmid":"36381627","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":[]}