Explainer | What’s known about ‘stealth’ version of Omicron?
- WHO monitoring Omicron sub-variant called BA. 2, which has been detected in more than 40 countries
- Dubbed ‘stealth Omicron’, sub-variant’s genetic traits make it somewhat harder to detect
Scientists and health officials around the world are keeping their eyes on a descendant of the Omicron variant that has been found in at least 40 countries.
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. As of Tuesday morning, 96 of those sequenced cases came from the United States.
“Thus far, we haven’t seen it start to gain ground” in the US, said Dr Wesley Long, a pathologist at Houston Methodist in Texas, which has identified three cases of BA.2.