A longitudinal seroprevalence survey of SARS-CoV-2 infection among health care workers and children

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K17271
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 58020:Hygiene and public health-related: including laboratory approach
• Research Institution: Nagasaki University (2023); Oita University (2021-2022)
• Principal Investigator: SAITO Nobuo 長崎大学, 熱帯医学研究所, 准教授 (60626018)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 新型コロナウイルス

Outline of Final Research Achievements

The aim of this study was to conduct seroepidemiological surveys of COVID-19 among healthcare and caregiving personnel and children in regional areas of Japan. Until August 2020, the antibody prevalence among healthcare and caregiving personnel was nearly 0%. A cross-sectional survey conducted from January 2007 to March 2022 investigated the SARS-CoV-2 IgG positivity rate among 2,557 pediatric patients not suspected of COVID-19 infection. Samples from the pre-pandemic period and from the first to the fourth waves tested negative, while positivity rates increased during the fifth and sixth waves, with a notable rise in the later waves.

Free Research Field

臨床疫学

Academic Significance and Societal Importance of the Research Achievements

本研究は、他疾患で病院を受診したが新型コロナウイルス感染が疑われない小児におけるSARS-CoV-2 IgGの保有率を明らかにし、流行時には症状のないまたは軽症で感染している小児が一定数存在していることを示した。本研究結果は、パンデミックの異なる時期の小児における抗体有病率の変動を示し、公衆衛生政策やワクチン接種戦略の最適化のために重要な情報を提供することができた。今後もこの集団に対する経時的な血清疫学調査の実施が地方においても重要であることを示した。