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. 2022 Apr;27(16):2200250.
doi: 10.2807/1560-7917.ES.2022.27.16.2200250.

Vaccine-induced and naturally-acquired protection against Omicron and Delta symptomatic infection and severe COVID-19 outcomes, France, December 2021 to January 2022

Milena Suarez Castillo  1   2 , Hamid Khaoua  2 , Noémie Courtejoie  2
Affiliations

Vaccine-induced and naturally-acquired protection against Omicron and Delta symptomatic infection and severe COVID-19 outcomes, France, December 2021 to January 2022

Milena Suarez Castillo et al. Euro Surveill. 2022 Apr.

Erratum in

  • Author's correction for Euro Surveill. 2022;27(16).
    Eurosurveillance editorial team. Eurosurveillance editorial team. Euro Surveill. 2022 Apr;27(17):220428c. doi: 10.2807/1560-7917.ES.2022.27.17.220428c. Euro Surveill. 2022. PMID: 35485268 Free PMC article. No abstract available.

Abstract

We assessed the protection conferred by naturally-acquired, vaccine-induced and hybrid immunity during the concomitant Omicron and Delta epidemic waves in France on symptomatic infection and severe COVID-19. The greatest levels of protection against both variants were provided by hybrid immunity. Protection against Omicron symptomatic infections was systematically lower and waned at higher speed than against Delta in those vaccinated. In contrast, there were little differences in variant-specific protection against severe inpatient outcomes in symptomatic individuals.

Keywords: SARS-CoV-2; Test negative design; immunity; vaccination effectiveness.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure 1
Figure 1
Variant-specific risk reduction of (A) symptomatic infections and (B) hospitalisations after symptomatic infections, among ≥ 18 year-olds, according to the time elapsed since each COVID-19 vaccine dose and evidence of prior SARS-CoV-2 infection, France, 13 December 2021–31 January 2022 (n = 761,744 Omicron and 166,009 Delta cases, respectively; n = 1,155,064 eligible controls)
Figure 2
Figure 2
Odd ratios of Omicron-attributable symptomatic infections among ≥18 year-olds, according to the time elapsed since each COVID-19 vaccine dose and/or evidence of prior infection, France, 13 December 2021–31 January 2022 (n = 761,744 Omicron cases; n = 1,155,064 eligible controls)
See this image and copyright information in PMC

References

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