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Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19
Published on: February 16, 2022
Anti-SARS-CoV-2 IgG levels in relation to disease severity of COVID-19
Xiquan Yan1,2, Guoqiang Chen3, Zhaoxia Jin4
1Department of Emergency Medicine, Hunan Provincial Institute of Emergency Medicine, Hunan Provincial Key Laboratory of Emergency and Critical Care Metabonomics, Hunan Provincial People's Hospital/The First Affiliated Hospital, Hunan Normal University, Changsha, Hunan, China.
Abstract:
The durability of infection-induced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity has crucial implications for reinfection and vaccine effectiveness. However, the relationship between coronavirus disease 2019 (COVID-19) severity and long-term anti-SARS-CoV-2 immunoglobulin G (IgG) antibody level is poorly understood. Here, we measured the longevity of SARS-CoV-2-specific IgG antibodies in survivors who had recovered from COVID-19 1 year previously. In a cohort of 473 survivors with varying disease severity (asymptomatic, mild, moderate, or severe), we observed a positive correlation between virus-specific IgG antibody titers and COVID-19 severity. In particular, the highest virus-specific IgG antibody titers were observed in patients with severe COVID-19. By contrast, 74.4% of recovered asymptomatic carriers had negative anti-SARS-CoV-2 IgG test results, while many others had very low virus-specific IgG antibody titers. Our results demonstrate that SARS-CoV-2-specific IgG persistence and titer depend on COVID-19 severity.
