biostudies-literatureUnknown25(1)Han J<h4>Background</h4>Coronavirus disease 2019 (COVID-19) continues to impact populations globally, raising concerns about immunity levels and risks to high-risk groups despite the lifting of the global health emergency in May 2023. While studies have tracked seroprevalence, few have comprehensively assessed long-term antibody persistence and COVID-19 risk, particularly regarding immunity changes due to vaccination and infection. This study aimed to estimate the population prevalence of SARS-CoV-2-specific antibodies, including anti-spike (anti-S) and anti-nucleocapsid (anti-N) antibodies, and to assess the risk of newly confirmed COVID-19 infections in Korea in December 2022. We conducted a follow-up survey and blood testing of 9,945 participants in the Korea Seroprevalence Study of MonitoriBMC infectious diseases1426https://www.ebi.ac.uk/biostudies/studies/S-EPMC12570802biostudies-literatureEffect of anti-S antibody titers on newly confirmed cases of COVID-19 in Korea: a community-based cohort study (K-SEROSMART Wave 2).PMC12570802Kim DHNoh EDo HLee SYLee KOKim ARHan JBaek HJKim JALee JWfalseEffect of anti-S antibody titers on newly confirmed cases of COVID-19 in Korea: a community-based cohort study (K-SEROSMART Wave 2).<h4>Background</h4>Coronavirus disease 2019 (COVID-19) continues to impact populations globally, raising concerns about immunity levels and risks to high-risk groups despite the lifting of the global health emergency in May 2023. While studies have tracked seroprevalence, few have comprehensively assessed long-term antibody persistence and COVID-19 risk, particularly regarding immunity changes due to vaccination and infection. This study aimed to estimate the population prevalence of SARS-CoV-2-specific antibodies, including anti-spike (anti-S) and anti-nucleocapsid (anti-N) antibodies, and to assess the risk of newly confirmed COVID-19 infections in Korea in December 2022. We conducted a follow-up survey and blood testing of 9,945 participants in the Korea Seroprevalence Study of Monitori2025-01-01T00:00:00Z2025 Oct2026-06-05T10:32:43.153Z2026-05-16T03:07:55.519ZS-EPMC125708024115282210.1186/s12879-025-11753-1