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. 2021 Sep;26(35):2100793.
doi: 10.2807/1560-7917.ES.2021.26.35.2100793.

Vaccine effectiveness against infection with the Delta (B.1.617.2) variant, Norway, April to August 2021

Elina Seppälä  1   2 , Lamprini Veneti  3 , Jostein Starrfelt  3 , Anders Skyrud Danielsen  3 , Karoline Bragstad  4 , Olav Hungnes  4 , Arne Michael Taxt  1 , Sara Viksmoen Watle  1 , Hinta Meijerink  1
Affiliations

Vaccine effectiveness against infection with the Delta (B.1.617.2) variant, Norway, April to August 2021

Elina Seppälä et al. Euro Surveill. 2021 Sep.

Abstract

Some variants of SARS-CoV-2 are associated with increased transmissibility, increased disease severity or decreased vaccine effectiveness (VE). In this population-based cohort study (n = 4,204,859), the Delta variant was identified in 5,430 (0.13%) individuals, of whom 84 were admitted to hospital. VE against laboratory confirmed infection with the Delta variant was 22.4% among partly vaccinated (95% confidence interval (CI): 17.0-27.4) and 64.6% (95% CI: 60.6-68.2) among fully vaccinated individuals, compared with 54.5% (95% CI: 50.4-58.3) and 84.4% (95%CI: 81.8-86.5) against the Alpha variant.

Keywords: : COVID-19 Vaccines; B.1.617.2; Delta variant of concern; Norway; SARS-CoV-2; Vaccine effectiveness.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure 1
Figure 1
Number of notified cases of COVID-19 by week of positive test result and cumulative number of vaccinated individuals by vaccine status and week; percentage of whole genome sequenced or PCR-screened COVID-19 cases and percentage of cases diagnosed with SARS-CoV-2 Delta and Alpha variants, Norway, 15 April–15 August 2021
See this image and copyright information in PMC

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