What Is Significance Of Covid-19 Omicron Variant?
Updated On May 25, 2022
This version of the coronavirus, which scientists call BA.2, is widely considered stealthier than the original version of Omicron because particular genetic traits make it somewhat harder to detect. Some scientists worry it could also be more contagious.
But they say there's a lot they still don't know about it, including whether it evades vaccines better or causes more severe disease.
Where Has It Spread?
Since mid-November, more than three dozen countries have uploaded nearly 15,000 genetic sequences of BA.2 to GISAID, a global platform for sharing coronavirus data. The mutant appears much more common in Asia and Europe. In Denmark, it made up 45% of all COVID-19 cases in mid-January, up from 20% two weeks earlier, according to Statens Serum Institut, which falls under the Danish Ministry of Health.
What's Known About This Version Of The Virus?
BA.2 has lots of mutations. About 20 of them in the spike protein that studs the outside of the virus are shared with the original Omicron. But it also has additional genetic changes not seen in the initial version.
For now, the original version, known as BA.1, and BA.2 are considered subsets of omicron. But global health leaders could give it its own Greek letter name if it is deemed a globally significant "variant of concern." The quick spread of BA.2 in some places raises concerns it could take off.
Doctors also don't yet know for sure if someone who's already had COVID-19 caused by Omicron can be sickened again by BA.2. But they're hopeful, especially that a prior Omicron infection might lessen the severity of disease if someone later contracts BA.2.
The original version of Omicron had specific genetic features that allowed health officials to rapidly differentiate it from Delta using a certain PCR test because of what's known as "S gene target failure."