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. 2021 Jul;26(28):2100573.
doi: 10.2807/1560-7917.ES.2021.26.28.2100573.

Rapid spread of the SARS-CoV-2 Delta variant in some French regions, June 2021

Samuel Alizon  1 , Stéphanie Haim-Boukobza  2 , Vincent Foulongne  3 , Laura Verdurme  2 , Sabine Trombert-Paolantoni  2 , Emmanuel Lecorche  2 , Bénédicte Roquebert  2 , Mircea T Sofonea  1
Affiliations

Rapid spread of the SARS-CoV-2 Delta variant in some French regions, June 2021

Samuel Alizon et al. Euro Surveill. 2021 Jul.

Abstract

We analysed 9,030 variant-specific RT-PCR tests performed on SARS-CoV-2-positive samples collected in France between 31 May and 21 June 2021. This analysis revealed rapid growth of the Delta variant in three of the 13 metropolitan French regions and estimated a +79% (95% confidence interval: 52-110%) transmission advantage compared with the Alpha variant. The next weeks will prove decisive and the magnitude of the estimated transmission advantages of the Delta variant could represent a major challenge for public health authorities.

Keywords: COVID-19; RT-PCR; epidemiology; simulations; statistical modelling; variant; virus.

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Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure 1
Figure 1
Change in relative frequency and estimated transmission advantage between SARS-CoV-2 Alpha, Beta/Gamma/Eta, and Delta variants in Hauts-de-France, Île-de-France, and Normandie, France, 31 May–21 June 2021
Figure 2
Figure 2
COVIDSIMa projections of the COVID-19 epidemic for different vaccine rollout and back-to-school effect scenarios, France, June 2021
See this image and copyright information in PMC

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