Discrepancy between frequent occurrence of COVID-19-like symptoms and low seroconversion rates among healthcare workers

Dehnen, Dorothea; Dehnen, Katja; Trilling, Mirko; Fiedler, Melanie; Drexler, Julia; Goralski, Marcel; Le-Trilling, Vu Thuy Khanh; Schöler, Lara; Jöckel, Karl-Heinz; Heßbrügge, Martina

BACKGROUND: During the first wave of the pandemic, we compared the occurrence of subjectively experienced COVID-19-like symptoms and true SARS-CoV-2 seroconversion rates among medical personnel in general practices. METHODS: This cross-sectional study determined the SARS-CoV-2-specific IgG antibody status of medical staff from 100 outpatient practices in Germany. Study cohort characteristics and COVID-19-like symptoms were obtained by questionnaires. The initial screening for SARS-CoV-2-recognizing antibodies was performed using a commercial chemiluminescence microparticle immunoassay. Positive results were controlled with another approved test. Samples with discrepant results were subjected to a third IgG-binding assay and a neutralization test. RESULTS: 861 participants were included, 1.7% (n = 15) of whom tested positive for SARS-CoV-specific IgG in the initial screening test. In 46.6% (n=7) of positive cases, test results were confirmed by an independent test. In the eight samples with discrepant results, neither spike-specific antibodies nor in-vitro neutralizing capacity were detectable, resulting in a genuine seroprevalence rate of 0.8%. 794 participants completed the questionnaire. Intriguingly, a total of 53.7% (n = 426) of them stated episodes of COVID-19-like symptoms Except for smell and taste dysfunction, there were no significant differences between the groups with and without laboratory-confirmed SARS-CoV-2 seroconversion. CONCLUSIONS: Our results demonstrated that only 0.8% of participants acquired SARS-CoV-2 even though 53.7% of participants reportedly experienced COVID-19-like symptoms. Thus, even among medical staff, self-diagnosis based on subjectively experienced symptoms does not have a relevant predictive value. This article is protected by copyright. All rights reserved.