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Sera neutralizing activities against SARS-CoV-2 and multiple variants six month after hospitalization for COVID-19

Abstract : Background: Humoral response to SARS-CoV-2 occurs within the first weeks after COVID-19. Those antibodies exert a neutralizing activity against SARS-CoV-2, whose evolution overtime after COVID-19 as well as efficiency against novel variants are however poorly characterized. Methods: In this prospective study, sera of 107 patients hospitalized with COVID-19 were collected at 3- and 6-months post-infection. We performed quantitative neutralization experiments on top of high-throughput serological assays evaluating anti-Spike (S) and anti-Nucleocapsid (NP) IgG. Findings: Levels of sero-neutralization and IgG rates against the ancestral strain decreased significantly over time. After 6 months, 2.8% of the patients had a negative serological status for both anti-S and anti-NP IgG. However, all sera had a persistent and effective neutralizing effect against SARS-CoV-2. IgG levels correlated with sero-neutralization and this correlation was stronger for anti-S than for anti-NP antibodies. The level of sero-neutralization quantified at 6 months correlated with markers of initial severity, notably admission in intensive care units and the need for mechanical invasive ventilation. In addition, sera collected at 6 months were tested against multiple SARS-CoV-2 variants and showed efficient neutralizing effects against D614G, B.1.1.7 and P.1 variants but a significantly weaker activity against B.1.351 variant. Interpretation: Decrease of IgG rates and serological assays becoming negative did not imply loss of neutralizing capacity. Our results indicate a sustained humoral response against the ancestral strain and the D614G, B.1.1.7 and P.1 variants for at least 6 months in patients previously hospitalized for COVID-19. A weaker protection was however observed for the B.1.351 variant.
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Contributor : Timothée Bruel Connect in order to contact the contributor
Submitted on : Wednesday, May 19, 2021 - 11:47:07 AM
Last modification on : Wednesday, September 28, 2022 - 4:20:12 PM
Long-term archiving on: : Friday, August 20, 2021 - 6:26:30 PM


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Maureen Betton, Marine Livrozet, Delphine Planas, Antoine Fayol, Blandine Monel, et al.. Sera neutralizing activities against SARS-CoV-2 and multiple variants six month after hospitalization for COVID-19. Clinical Infectious Diseases, Oxford University Press (OUP), 2021, pp.ciab308. ⟨10.1093/cid/ciab308⟩. ⟨pasteur-03229817⟩



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