Antibody seroprevalence and rate of asymptomatic infections with SARS-CoV-2 in Austrian hospital personnel

BMC Infectious Diseases

Barbara Holzer¹  Matthias Hackl²  Ivo Ponocny³  Elisabeth Ponocny-Seliger⁴  Herwig Kollaritsch⁵  Markus Exner⁶  Claudia Wilfing⁷  Michaela Stainer⁸  Peter Dungel⁸  Heinz Redl⁸  Wolfgang Schaden⁹  Rainer Mittermayr^1,10  Thomas Hausner^1,10  Johannes Grillari^1,11  Ludwig Aigner^1,12  Iris Leister^1,13 

[1] Austrian Agency for Health and Food Safety, Mödling, Austria;Austrian Cluster for Tissue Regeneration, Vienna, Austria;TAmiRNA GmbH, Vienna, Austria;Department for Applied Statistics and Economics, Modul University Vienna, Vienna, Austria;Institute for Quantitative Methods, Sigmund Freud Private University, Vienna, Austria;Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Vienna, Austria;Labors.at GmbH, Vienna, Austria;Ludwig-Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria;Ludwig-Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria;Austrian Cluster for Tissue Regeneration, Vienna, Austria;Ludwig-Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria;Austrian Cluster for Tissue Regeneration, Vienna, Austria;AUVA Headquarter, Vienna, Austria;Ludwig-Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria;Austrian Cluster for Tissue Regeneration, Vienna, Austria;AUVA Trauma Center Vienna, Vienna, Austria;Ludwig-Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria;Austrian Cluster for Tissue Regeneration, Vienna, Austria;Department of Biotechnology, Institute of Molecular Biotechnology, BOKU – University of Natural Resources and Life Sciences, Vienna, Austria;ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria;Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria;ParaMove, SCI Research Unit, BG Trauma Center Murnau, Murnau, Germany, and Paracelsus Medical University, Salzburg, Austria;Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria;Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS) and ParaMove, Paracelsus Medical University, Salzburg, Austria;

关键词: Severe acute respiratory syndrome coronavirus 2;    SARS-CoV-2;    COVID-19 diagnostic testing;   

DOI  :  10.1186/s12879-021-06586-7

来源: Springer

【 摘 要 】

BackgroundThe aims of this study are to determine (i) SARS-CoV-2 antibody positive employees in Austrian trauma hospitals and rehabilitation facilities, (ii) number of active virus carriers (symptomatic and asymptomatic) during the study, (iii) antibody decline in seropositive subjects over a period of around 6 months, (iv) the usefulness of rapid antibody tests for outpatient screening.MethodA total of 3301 employees in 11 Austrian trauma hospitals and rehabilitation facilities of the Austrian Social Insurance for Occupational Risks (AUVA) participated in this open uncontrolled prospective cohort study.Rapid lateral flow tests, detecting a combination of IgM and IgM against SARS-CoV-2), two different types of CLIA (Diasorin, Roche), RT-PCR tests and serum neutralization tests (SNTs) were performed. The tests were conducted twice, with an interval of 42.4 ± 7.7 (Min = 30, Max = 64) days. Positive participants were re-tested with CLIA/SNT at a third time point after 188.0 ± 12.8 days.ResultsOnly 27 out of 3301 participants (0.82%) had a positive antibody test at any time point during the study confirmed via neutralization test. Among positively tested participants in either test, 50.4% did not report any symptoms consistent with common manifestations of COVID-19 during the study period or within the preceding 6 weeks. In the group who tested positive during or prior to study inclusion the most common symptoms of an acute viral illness were rhinitis (21.9%), and loss of taste and olfactory sense (21.9%).Based on the neutralization test as the true condition, the rapid antibody test performed better on serum than whole blood as 84.6% instead of 65.4% could be detected correctly. Concerning both CLIA tests overall the Roche test detected 24 (sensitivity = 88.9%) and the Diasorin test 22 positive participants (sensitivity = 81.5%).In participants with a positive SNT result, a significant drop in neutralizing antibody titre from 31.8 ± 22.9 (Md = 32.0) at T1 to 26.1 ± 17.6 (Md = 21.3) at T2 to 21.4 ± 13.4 (Md = 16.0) at T3 (χ2 = 23.848, df = 2, p < 0.001) was observed (χ2 = 23.848, df = 2, p < 0.001)—with an average time of 42.4 ± 7.7 days between T1 and T2 and 146.9 ± 13.8 days between T2 and T3.ConclusionsDuring the study period (May 11th–August 3rd) only 0.82% were tested positive for antibodies in our study cohort. The antibody concentration decreases significantly over time with 14.8% (4 out of 27) losing detectable antibodies.

【 授权许可】

CC BY