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Abstract

We included 39,524 COVID-19 Omicron and 51,481 Delta cases reported in Norway from December 2021 to January 2022. We estimated a 73% reduced risk of hospitalisation (adjusted hazard ratio: 0.27; 95% confidence interval: 0.20–0.36) for Omicron compared with Delta. Compared with unvaccinated groups, Omicron cases who had completed primary two-dose vaccination 7–179 days before diagnosis had a lower reduced risk than Delta (66% vs 93%). People vaccinated with three doses had a similar risk reduction (86% vs 88%).

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/content/10.2807/1560-7917.ES.2022.27.4.2200077
2022-01-27
2022-11-30
http://instance.metastore.ingenta.com/content/10.2807/1560-7917.ES.2022.27.4.2200077
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References

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