Sensitivity of the Elecsys Nucleocapsid Assay for the Detection of Preceding SARS-CoV-2 Infections

Brian Grunau; Janessa Tom; Michael Asamoah-Boaheng; Sheila F O'Brien; Steven J Drews; Sadaf Sediqi; Pascal M Lavoie; Vilte Barakauskas; David M Goldfarb

doi:10.1093/ofid/ofac349

Sensitivity of the Elecsys Nucleocapsid Assay for the Detection of Preceding SARS-CoV-2 Infections

Open Forum Infect Dis. 2022 Jul 26;9(8):ofac349. doi: 10.1093/ofid/ofac349. eCollection 2022 Aug.

Authors

Brian Grunau¹, Janessa Tom², Michael Asamoah-Boaheng³, Sheila F O'Brien⁴, Steven J Drews⁴, Sadaf Sediqi⁵, Pascal M Lavoie⁶, Vilte Barakauskas⁵, David M Goldfarb⁵

Affiliations

¹ Centre for Health Evaluation & Outcome Sciences, St. Paul's Hospital, Vancouver, British Columbia, Canada.
² British Columbia Emergency Health Services, Vancouver, British Columbia, Canada.
³ Department of Emergency Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
⁴ Canadian Blood Services, Ottawa, Ontario, Canada.
⁵ Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
⁶ Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada.

Abstract

Nucleocapsid serological assay sensitivity to identify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections among vaccinees and for Omicron cases is unclear. In this prospective study, the Elecsys nucleocapsid assay was 89% sensitive in identifying SARS-CoV-2 infections 14-607 days pre-blood collection. Sensitivity was similar when comparing by vaccination status, and in Omicron (vs pre-Omicron) cases.

Keywords: COVID-19; SARS-CoV-2; antibodies; nucleocapsid; vaccine.