Reduction in the infection fatality rate of Omicron variant compared with previous variants in South Africa

International Journal of Infectious Diseases

卷:120

Yanji Zhao¹  Daihai He²  Yuan Liu²  Yangyang Yu² 

[1] State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, China;

[2] Department of Applied Mathematics, Hong Kong Polytechnic University, Hong Kong SAR, China;

关键词: COVID-19;    Omicron;    Infection fatality rate;    Immune evasion;   

DOI  :  

来源: DOAJ

【 摘 要 】

Objective: The SARS-CoV-2 Omicron (B.1.1.529) variant has caused global concern. Previous studies have shown that the variant has enhanced immune evasion ability and transmissibility and reduced severity. Methods: In this study, we developed a mathematical model with time-varying transmission rate, vaccination, and immune evasion. We fit the model to reported case and death data up to February 6, 2022 to estimate the transmissibility and infection fatality ratio of the Omicron variant in South Africa. Results: We found that the high relative transmissibility of the Omicron variant was mainly due to its immune evasion ability, whereas its infection fatality rate substantially decreased by approximately 78.7% (95% confidence interval: 66.9%, 85.0%) with respect to previous variants. Conclusion: On the basis of data from South Africa and mathematical modeling, we found that the Omicron variant is highly transmissible but with significantly lower infection fatality rates than those of previous variants of SARS-CoV-2.

【 授权许可】

Unknown