The latest U.K. Health Security Agency (UKHSA) Technical Briefing on variants of concern reports that the Omicron BA.2 variant, which is now dominant in the U.K. and in many countries around the world, is even milder than the original Omicron BA.1 variant, which was responsible for the very low death toll this winter.
The report states:
Analyses of sequenced cases up to March 8th 2022 have been undertaken to compare the risk of hospitalisation, as defined by admission as an inpatient, or presentation to emergency care that resulted in admission, transfer or death, following BA.2 compared to BA.1. This analysis adjusted for age, reinfection status, sex, ethnicity, local area deprivation and vaccination status. It also controlled for the effect of geography and specimen date. The risk of hospitalisation does not appear to be higher following a BA.2 infection than following a BA.1 infection (hazard ratio 0.94 95% CI: 0.88-1.00).
The hazard ratio of 0.94 means BA.2 comes with 6% lower risk of hospitalisation compared to BA.1. The 95% confidence interval (CI) of 0.88-1.00 means the researchers are 95% sure the variant is not a higher risk than BA.1, and it may be up to 12% lower. These figures are adjusted for confounders such as age and vaccination status, and also geography for some reason. Admittedly, it’s not a big drop, but it’s in the right direction, and it means up to 12% fewer people may be hospitalised in the current surge, which is a good thing.