Kathrine Agergård Kaspersen

Long-term detection of SARS-CoV-2 antibodies after infection and risk of re-infection

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

  • Bo Langhoff Hønge
  • Lotte Hindhede
  • Kathrine Agergård Kaspersen
  • Lene Holm Harritshøj, University of Copenhagen
  • ,
  • Susan Mikkelsen
  • Dorte Kinggaard Holm, University of Southern Denmark
  • ,
  • Anna Christine Nilsson, University of Southern Denmark
  • ,
  • Susanne Gjørup Sækmose, Sjællands Universitetshospital
  • ,
  • Erik Sørensen, University of Copenhagen
  • ,
  • Bitten Aagaard, Aalborg University
  • ,
  • Henrik Hjalgrim, Statens Serum Institut, University of Copenhagen
  • ,
  • Charlotte Sværke Jørgensen, Statens Serum Institut
  • ,
  • Tyra Grove Krause, Statens Serum Institut
  • ,
  • Henrik Ullum, Statens Serum Institut
  • ,
  • Ole Birger Vestager Pedersen, Sjællands Universitetshospital, University of Copenhagen
  • ,
  • Sisse Rye Ostrowski, University of Copenhagen
  • ,
  • Christian Erikstrup

Objectives: To evaluate long-term sensitivity for detection of total antibodies against SARS-CoV-2 Methods: From week 41, 2020, through week 26, 2021, all Danish blood donations were tested for SARS-CoV-2 antibodies with the Wantai assay. The results were linked with polymerase chain reaction (PCR) test results from the Danish Microbiological Database (MiBa). Results: During the study period, 105,646 non-vaccinated Danish blood donors were tested for SARS-CoV-2 antibodies, and 3,806 (3.6%) had a positive PCR test before the blood donation. Among the donors with a positive PCR test, 94.2% subsequently also had a positive antibody test. The time between the positive PCR test and the antibody test was up to 15 months and there was no evidence of a decline in proportion with detectable antibodies over time. A negative serological result test was associated with a higher incidence of re-infection (Incidence Rate Ratio = 0.102 (95% confidence interval (CI): 0.039–0.262)). Conclusion: Among healthy blood donors, 94.2% developed SARS-CoV-2 antibodies after infection, and a lack of detectable antibodies was associated with re-infection.

Original languageEnglish
JournalInternational Journal of Infectious Diseases
Pages (from-to)289-292
Number of pages4
Publication statusPublished - Mar 2022

    Research areas

  • blood donors, SARS-CoV-2, sensitivity, seroprevalence, Wantai

See relations at Aarhus University Citationformats

ID: 263801686