ArticleEmerging infectious diseases2022
Age-Stratified Seroprevalence of SARS-CoV-2 Antibodies before and during the Vaccination Era, Japan, February 2020-March 2022.
Article in Emerging infectious diseases, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
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Who cites it
5 citing papers in PubMed, 5 citations in OpenAlex.
- Using forensic autopsy data to estimate the age-specific infection fatality risk of COVID-19.Epidemiology and infection · 2026Article
- Three-year Seroprevalence of SARS-CoV-2 Nucleocapsid Protein Antibody Among Children, Parental Awareness, and Contributors of Infection: A Single-school Cohort Study in Chiba, Japan.Journal of epidemiology · 2025Article
- Seroprevalence of severe acute respiratory syndrome coronavirus 2 N antibodies between December 2021 and march 2023 in Japan.Epidemiology and infection · 2024Article
- Seroprevalence of SARS-CoV-2 antibodies in dogs and cats during the early and mid-pandemic periods in Japan.One health (Amsterdam, Netherlands) · 2023Article
- Infection-Induced SARS-CoV-2 Seroprevalence among Blood Donors, Japan, 2022.Emerging infectious diseases · 2023Article
Corrections and comments
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Authors and funding
28 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Japan has reported a relatively small number of COVID-19 cases. Because not all infected persons receive diagnostic tests for COVID-19, the reported number must be lower than the actual number of infections. We assessed SARS-CoV-2 seroprevalence by analyzing >60,000 samples collected in Japan (Tokyo Metropolitan Area and Hokkaido Prefecture) during February 2020-March 2022. The results showed that ≈3.8% of the population had become seropositive by January 2021. The seroprevalence increased with the administration of vaccinations; however, among the elderly, seroprevalence was not as high as the vaccination rate. Among children, who were not eligible for vaccination, infection was spread during the epidemic waves caused by the SARS-CoV-2 Delta and Omicron variants. Nevertheless, seroprevalence for unvaccinated children <5 years of age was as low as 10% as of March 2022. Our study underscores the low incidence of SARS-CoV-2 infection in Japan and the effects of vaccination on immunity at the population level.
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