ArticleThe Lancet regional health. Europe2022
Seroprevalence and infection fatality rate of the SARS-CoV-2 Omicron variant in Denmark: A nationwide serosurveillance study.
Article in The Lancet regional health. Europe, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 41 papers, 1 of them a synthesis that pooled it.
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Who cites it
41 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Age-stratified infection fatality rate of COVID-19 in the non-elderly population.Environmental research · 2023Pooled it
- Precision transfusion medicine in the omics era.Blood · 2026Review
- Inverted "u-shaped" association of cold-water immersion frequency with mental health and upper respiratory tract infection: a cross-sectional study.Brain, behavior, & immunity - health · 2025Article
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- Comparison of Infection-Induced SARS-CoV-2 Seroprevalence Across Large-Scale Residual Samples From Blood Donors, Commercial Laboratories, and Health Checkups in Japan, 2023.Open forum infectious diseases · 2025Article
- Age associated SARS-CoV-2 immune responses provide insights into population immunity over four years since the COVID-19 pandemic.Scientific reports · 2025Article
- Estimates of SARS-CoV-2 Infections and Population Immunity After the COVID-19 Pandemic in Austria: Analysis of National Wastewater Data.The Journal of infectious diseases · 2025Article
- A data science pipeline applied to Australia's 2022 COVID-19 Omicron waves.Infectious Disease Modelling · 2025Article
- Interpreting the Influence of Using Blood Donor Residual Samples for SARS-CoV-2 Seroprevalence Studies in Japan: Cross-Sectional Survey Study.JMIR public health and surveillance · 2025Article
- Death risk in nursing homes between the prepandemic period and the COVID-19 era: a retrospective cohort study in Murcia Region, Spain.BMJ public health · 2025Article
- Dynamics of SARS-CoV-2 infection over two epidemic waves in Manaus, Brazil: A serological study of seven thousand blood donors.PloS one · 2025Article
- What Lessons can Be Learned From the Management of the COVID-19 Pandemic?International journal of public health · 2025Review
- Detection of Nucleocapsid Antibodies Associated with Primary SARS-CoV-2 Infection in Unvaccinated and Vaccinated Blood Donors.Emerging infectious diseases · 2024Article
- Excess mortality in Denmark, Finland, Norway and Sweden during the COVID-19 pandemic 2020-2022.European journal of public health · 2024Article
- Review
- Effectiveness of a fourth SARS-CoV-2 vaccine dose in previously infected individuals from Austria.European journal of clinical investigation · 2024Observational
- Clinical outcomes in hospitalized plasma and platelet transfusion recipients prior to and following widespread blood donor SARS-CoV-2 infection and vaccination.Transfusion · 2024Article
- Article
- Epidemiological features of SARS-CoV-2 Omicron infection under new control strategy: a cross-sectional study of the outbreak since December 2022 in Sichuan, China.BMC public health · 2023Observational
- Rapid antigen testing for COVID-19: Decreasing diagnostic reliability, potential detrimental effects and a lack of evidence to support continued public funding of community-based testing.Public health in practice (Oxford, England) · 2023Article
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27 authors.
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Abstract
Background: Introduction of the Omicron variant caused a steep rise in SARS-CoV-2 infections despite high vaccination coverage in the Danish population. We used blood donor serosurveillance to estimate the percentage of recently infected residents in the similarly aged background population with no known comorbidity. Methods: To detect SARS-CoV-2 antibodies induced due to recent infection, and not vaccination, we assessed anti-nucleocapsid (anti-N) immunoglobulin G (IgG) in blood donor samples. Individual level data on SARS-CoV-2 RT-PCR results and vaccination status were available. Anti-N IgG was measured fortnightly from January 18 to April 3, 2022. Samples from November 2021 were analysed to assess seroprevalence before introduction of the Omicron variant in Denmark. Findings: A total of 43 088 donations from 35 309 Danish blood donors aged 17-72 years were screened. In November 2021, 1·2% (103/8 701) of donors had detectable anti-N IgG antibodies. Adjusting for test sensitivity (estimates ranging from 74%-81%) and November seroprevalence, we estimate that 66% (95% confidence intervals (CI): 63%-70%) of the healthy, similarly aged Danish population had been infected between November 1, 2021, and March 15, 2022. One third of infections were not captured by SARS-CoV-2 RT-PCR testing. The infection fatality rate (IFR) was 6·2 (CI: 5·1-7·5) per 100 000 infections. Interpretation: Screening for anti-N IgG and linkage to national registers allowed us to detect recent infections and accurately assess assay sensitivity in vaccinated or previously infected individuals during the Omicron outbreak. The IFR was lower than during previous waves. Funding: The Danish Ministry of Health.
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