WHO designated the variant B.1.1.529 a variant of concern, named Omicron, on the advice of WHO’s Technical Advisory Group on Virus Evolution (TAG-VE). It is not yet clear whether Omicron is more transmissible compared to other variants, including Delta. The number of people testing positive has risen in areas of South Africa affected by this variant, but epidemiologic studies are underway. It is not yet clear whether infection with Omicron causes more severe disease compared to infections with other variants, including Delta. Preliminary data suggests that there are increasing rates of hospitalization in South Africa, but this may be due to increasing overall numbers of people becoming infected, rather than a result of specific infection with Omicron. there may be an increased risk of reinfection with Omicron as compared to other variants of concern, but information is limited. The widely used PCR tests continue to detect infection, including infection with Omicron, as we have seen with other variants as well.
Source: WHO