Anti-SARS-CoV-2 Nucleocapsid Antibody Positivity Three Years after COVID-19

Jpn J Infect Dis. 2024 Sep 19;77(5):285-288. doi: 10.7883/yoken.JJID.2024.011. Epub 2024 Apr 30.

Abstract

The accurate identification of individuals without prior infection with severe acute respiratory syndrome coronavirus 2 is pivotal for seroepidemiological studies and vaccine trials. Owing to widespread vaccination against coronavirus disease 2019 (COVID-19), the anti-nucleocapsid antibody continues to serve as a valuable marker for individuals without a history of COVID-19. This study aimed to comprehensively assess anti-nucleocapsid antibody positivity using diverse commercial and in-house immunoassays among individuals who contracted COVID-19 more than three years earlier. We enrolled 44 participants with laboratory-confirmed COVID-19 between January and May 2020 from the Seoul National University Hospital and its community treatment centers. The results showed anti-nucleocapsid antibody positivity ranging from 45.5% to 87.9%, depending on the immunoassay. This study highlights the importance of considering the limited anti-nucleocapsid antibody positivity in individuals, with a history of distant COVID-19, in seroepidemiological or vaccine research.

Keywords: 3 years; COVID-19; SARS-CoV-2; anti-nucleocapsid antibody; positivity.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Viral* / blood
  • COVID-19 Serological Testing / methods
  • COVID-19* / epidemiology
  • COVID-19* / immunology
  • Female
  • Humans
  • Immunoassay / methods
  • Male
  • Middle Aged
  • Nucleocapsid / immunology
  • Phosphoproteins / immunology
  • Republic of Korea / epidemiology
  • SARS-CoV-2* / immunology
  • Seroepidemiologic Studies

Substances

  • Antibodies, Viral
  • Phosphoproteins