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Published on: June 5, 2021
Antibody avidity maturation during severe acute respiratory syndrome-associated coronavirus infection
Paul K S Chan1, Pak-Leong Lim, Esther Y M Liu
1Centre for Emerging Infectious Diseases, Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong Special Administrative Region, People's Republic of China. paulkschan@cuhk.edu.hk
Abstract:
The maturation of virus-specific immunoglobulin G avidity during severe acute respiratory syndrome-associated coronavirus infection was examined. The avidity indices were low (mean +/- SD, 30.8% +/- 11.6%) among serum samples collected < or =50 days after fever onset, intermediate (mean +/- SD, 52.1% +/- 14.1%) among samples collected between days 51 and 90, and high (mean +/- SD, 78.1% +/- 8.0%) among samples collected after day 90. Avidity indices of 40% and 55% could be considered as cutoff values for determination of recent (< or =50 days) and past (>65 days) infection, respectively. Measurement of antibody avidity can be used to differentiate primary infection from reexposure and to assess humoral responses to candidate vaccines.
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