First noted by the World Health Organization on Tuesday, January 24, the so-called Stealth Omicron variant of the coronavirus has been detected in at least 40 countries across the world, although much is unknown about it, including how severe it might be.
Referred to as “Omicron variant BA.2,” it has been picked up in Europe, India and the United States, among many other countries.
However, at present, it is widely considered to be stealthier than even the original version of Omicron because its genetic traits make it a bit harder to detect. Some experts believe it may even be more contagious than the very easily spread Omicron, but very little is known about that aspect of the subvariant at present, including how susceptible it is to vaccines.
GISAID, the global clearinghouse for coronavirus data, reports that more than three dozen nations have uploaded as many as 15,000 genetic sequences of BA.2, with 96 of those sequenced cases coming from the US as of Tuesday.
Dr. Wesley Long, a pathologist at Houston Methodist in Texas, told interviewers from CBS News “Thus far, we haven’t seen it start to gain ground” in the US.
As of now, the “Stealth” variant has appeared much more commonly in Asia and Europe. Incredibly, it made up 45% of all coronavirus cases in mid-January in Denmark — more than doubling from the 20% detected just two weeks prior, according to information shared by the Statens Serum Institut, part of the Danish Ministry of Health.
As we have seen so often in earlier manifestations of the coronavirus, BA.2 itself already has a number of mutations. Scientists say approximately 20 of them inside the spike protein that is seen on the outside of the virus are in common with the original Omicron variant.
However, it also has other genetic changes that were not present in the initial version.
Another Greek letter may be on the horizon
Dr. Jeremy Luban, a virologist at the University of Massachusetts Medical School, tells CBS that at this point, it is not clear if these mutations are significant — especially in people who have already encountered the original Omicron.
Stealth BA.1 and BA.2 are considered subsets of omicron as of now; however, the WHO may bestow on it its own Greek letter name if it is believed to be a significant “variant of concern” around the world.
The rapid spread of BA.2 in some areas raises the question of just how fast it may spread throughout the entire world.
“We have some indications that it just may be as contagious or perhaps slightly more contagious than (original) Omicron since it’s able to compete with it in some areas,” Long stated, adding “But we don’t necessarily know why that is.”
In Denmark, where it is already especially prevalent, investigations have shown that there are no additional hospitalizations associated with the new subvariant. Separate investigations are looking into how the subvariant may be more or less susceptible to vaccines and treatments that are available.
At this point it is also unknown if recovery from a previous variant provides protection against Stealth Omicron.