Abstract
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.
Keywords: COVID-19; Immune evasion; Infection fatality rate; Omicron.
【저자키워드】 COVID-19, omicron, immune evasion, Infection fatality rate, 【초록키워드】 SARS-CoV-2, vaccination, severity, variant, Infection, omicron, variants, immune evasion, South Africa, Transmissibility, mathematical model, death, Omicron variant, B.1.1.529, fatality, Previous studies, 95% confidence interval, Fatality rate, previous study, significantly lower, transmission rate, variants of SARS-CoV-2, shown, caused, reported, reduced, mathematical, 【제목키워드】 Infection, Fatality rate,