Stealth omicron: What is it and where is it spreading?

Omicron subvariant has spread to at least 40 countries, including US

FILE - A dose of a Pfizer COVID-19 vaccine is prepared at Lurie Children's hospital, Nov. 5, 2021, in Chicago. Three new U.S. studies offer more evidence that the COVID-19 vaccines are standing up to the omicron variant, at least among people who have received booster shots. The Centers for Disease Control and Prevention released the studies, Friday. Jan. 21, 2022. (AP Photo/Nam Y. Huh, File) (Nam Y. Huh, Copyright 2021 The Associated Press. All rights reserved.)

The Omicron BA.2 subvariant, also known as “stealth omicron,” has spread across 40 countries, including the United States, according to a recent report by Newsweek.

The subvariant, first announced by The U.K. Health and Security Agency on Jan. 21, is currently under investigation and has been identified in 53 samples across the U.K., a Forbes report said.

A Newsweek article said this new BA.2 subvariant is thought to be more contagious than its BA.1 counterpart, as indicated by studies conducted in Denmark and Norway labs.

[TRENDING: Brother of high-profile missing Florida woman found dead, police say | Sorry, Central Florida. That wasn’t snow Saturday night | Become a News 6 Insider (it’s free!)]

Data shows that the new subvariant is responsible for nearly half of all omicron COVID-19 cases as of Jan. 20.

According to Newsweek, GISAID marked a total of 12,842 BA.2 sequences in its database, including 67 within the U.S.

The U.K.’s Health Security Agency said the BA.2 variant is classified as under investigation due to its spread outpacing that of BA.1, despite the proportion of BA.2 in the U.K. remaining low at this time, according to Forbes.

The Newsweek report shows that, as of Monday, at least 40 countries, and possibly 49, have denoted BA.2 viral sequences since Nov. 17.

As this subvariant doesn’t share any of the same genetic characteristics as its sister variant, scientists have called the BA.2 variation “stealth omicron,” Newsweek continues. Scientists do argue that stealth omicron shows up in PCR testing as a positive result for COVID-19, despite its given nickname.

It is not yet known whether this emergent subvariant is more severe than its counterpart, but their genetic differences can possibly impact severity of infection, Forbes said. COVID-19 vaccines, however, are believed to prevent severe illness in this new subvariant.