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. 2022 Jan;27(2):2101197.
doi: 10.2807/1560-7917.ES.2022.27.2.2101197.

Waning antibody levels after COVID-19 vaccination with mRNA Comirnaty and inactivated CoronaVac vaccines in blood donors, Hong Kong, April 2020 to October 2021

Shirley Ll Kwok  1   2 , Samuel Ms Cheng  1   3   4 , Jennifer Ns Leung  5 , Kathy Leung  1   2 , Cheuk-Kwong Lee  5 , Js Malik Peiris  1   3   4 , Joseph T Wu  1   2
Affiliations

Waning antibody levels after COVID-19 vaccination with mRNA Comirnaty and inactivated CoronaVac vaccines in blood donors, Hong Kong, April 2020 to October 2021

Shirley Ll Kwok et al. Euro Surveill. 2022 Jan.

Erratum in

  • Erratum for Euro Surveill. 2022;27(2).
    Eurosurveillance editorial team. Eurosurveillance editorial team. Euro Surveill. 2022 Jan;27(3):220120e. doi: 10.2807/1560-7917.ES.2021.27.3.220120e. Euro Surveill. 2022. PMID: 35057903 Free PMC article. No abstract available.

Abstract

The mRNA vaccine Comirnaty and the inactivated vaccine CoronaVac are both available in Hong Kong's COVID-19 vaccination programme. We observed waning antibody levels in 850 fully vaccinated (at least 14 days passed after second dose) blood donors using ELISA and surrogate virus neutralisation test. The Comirnaty-vaccinated group's (n = 593) antibody levels remained over the ELISA and sVNT positive cut-offs within the first 6 months. The CoronaVac-vaccinated group's (n = 257) median antibody levels began to fall below the cut-offs 4 months after vaccination.

Keywords: BNT162b2; COVID-19; CoronaVac; SARS-CoV-2; antibody; vaccine.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure
Figure
SARS-CoV-2 antibody responses in vaccinated blood donors from 14 days to 6 months after vaccination with Comirnaty (A, C)a or CoronaVac (B, D)b, Hong Kong, April 2020–October 2021 (n = 850)
See this image and copyright information in PMC

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