The disease severity of COVID-19 caused by Omicron variants: A brief review

Kohei Uemura; Takumi Kanata; Sachiko Ono; Nobuaki Michihata; Hideo Yasunaga

doi:10.37737/ace.23005

The disease severity of COVID-19 caused by Omicron variants: A brief review

Ann Clin Epidemiol. 2023 Apr 1;5(2):31-36. doi: 10.37737/ace.23005. eCollection 2023.

Authors

Kohei Uemura¹, Takumi Kanata¹, Sachiko Ono², Nobuaki Michihata³, Hideo Yasunaga⁴

Affiliations

¹ Department of Biostatistics & Bioinformatics, Graduate School of Medicine, The University of Tokyo.
² Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo.
³ Department of Health Services Research, Graduate School of Medicine, The University of Tokyo.
⁴ Department of Clinical Epidemiology & Health Economics, School of Public Health, The University of Tokyo.

Abstract

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in November 2021 and spread worldwide. This review summarizes the reported mortality and morbidity rates of coronavirus disease (COVID-19) caused by Omicron variants. In 21 previous studies, the mortality of patients infected with Omicron variants ranged from 0.01 to 13.1%, whereas that of those infected with previous variants was from 0.08% to 29.1%. The proportions of intensive care unit admissions and mechanical ventilation were lower for Omicron variants than for the previous variants. Future studies should clarify the mechanisms of transmissibility and severity of COVID-19 caused by the Omicron variants.

Keywords: COVID-19; Omicron variant.

Publication types

Review