Study | Location | Study date | Method | Estimated R0 | Other findings |
---|---|---|---|---|---|
Khan et al. | South Africa | November 2021 to January 2022 | Using a mathematical model using the Omicron feature and the accurate data of infected cases | R value = 2.1107 | |
Nishiura et al. | Gauteng province, South Africa | end of November 2021 | Using the data from GISAID, the effective reproduction number of the Omicron variant (Rt) was calculated by assuming that the Rt of omicron is given by multiplying a constant factor k by that of the Delta variant | Rt of the omicron variant: 4.2 times (95% CI 2.1, 9.1) higher than the Rt of the delta variant | |
Jalali et al. | Norway | December 2021 to January 2022 | Use contact tracing data collected by Norwegian municipalities to estimate and compare household | SAR for Omicron variant: 51% (95% CI 48–54) SAR for delta variant: 36% (95% CI 33–40) RR = 1.41 (95% CI 1.27–1.56) VE for Omicron variant = 45% (CI 95 26–57) VE for delta variant = 65% (CI 95 42–80) | |
South Africa | Up to 25 April 2022 | The multinomial logistic regression model | Growth advantages for BA.4 over BA.2 = 0.08 (95% CI 0.07–0.09) Growth advantages for BA.5 over BA.2 = 0.12 (95% CI 0.09–0.15) |