biostudies-literatureFischer BMedizinische Fakultät, Ruhr-Universität Bochume0279195https://www.ebi.ac.uk/biostudies/studies/S-EPMC9757571biostudies-literatureUnknown17(12)Seroprevalence studies can contribute to a better assessment of the actual incidence of infection. Since long-term data for Germany are lacking, we determined the seroprevalence of immunoglobulin G (IgG) antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in residual plasma samples of 3,759 German regular blood donors between July 2020 and June 2021. Over almost the entire study period, the incidences determined based on our data were higher than those officially reported by the Robert Koch Institute, the public health institute in Germany. Using our serological testing strategy, we retrospectively detected natural infection in 206/3,759 (5.48%; 95% confidence interval (CI): 4.77-6.25) individuals. The IgG seroprevalence ranked from 5.15% (95% CI: 3.73-6.89) in PloS oneAnalysis of a German blood donor cohort reveals a high number of undetected SARS-CoV-2 infections and sex-specific differences in humoral immune response.PMC9757571F1009-2021Fischer BKnabbe CVollmer TfalseAnalysis of a German blood donor cohort reveals a high number of undetected SARS-CoV-2 infections and sex-specific differences in humoral immune response.Seroprevalence studies can contribute to a better assessment of the actual incidence of infection. Since long-term data for Germany are lacking, we determined the seroprevalence of immunoglobulin G (IgG) antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in residual plasma samples of 3,759 German regular blood donors between July 2020 and June 2021. Over almost the entire study period, the incidences determined based on our data were higher than those officially reported by the Robert Koch Institute, the public health institute in Germany. Using our serological testing strategy, we retrospectively detected natural infection in 206/3,759 (5.48%; 95% confidence interval (CI): 4.77-6.25) individuals. The IgG seroprevalence ranked from 5.15% (95% CI: 3.73-6.89) in 2022-01-01T00:00:00Z20222025-04-04T19:49:23.094Z2024-11-06T23:02:54.947ZS-EPMC97575713652544910.1371/journal.pone.0279195