All You Need To Know About the New COVID Variant, BA.2
Written by Leslie K. Hughes
Medically reviewed by Dr. Monique White-Dominguez
Omicron hit the world scene hard with a record-setting number of cases. There were 15 million new cases of COVID in a single week back in mid-January. However, we are starting to see those numbers taper off a bit, and data shows that new COVID infections have dropped more than 30% since that time.
Though we reached new highs for infection rates, the good news is that omicron isn’t hitting people as hard as previous variants did. Omicron is proving to be a less severe infection than the strains that came before it, so while the numbers are higher, concerns are not as high as they have been in the past.
That doesn’t mean that it’s time to let your guard down, however. A new COVID variant has emerged. This one is a different version of omicron, and has been given the name “stealth omicron.”
What is the new COVID-19 variant of interest?
Its scientific name is BA.2 and this strain is a subvariant of omicron (also called BA.1). That essentially means that it is related to omicron and thus has some similarities, but features some new mutations as well.
Because this variant has similar genetics to omicron, scientists decided it didn’t warrant having its own name created and instead defined it as a relative of BA.1 (the original omicron).
Why is this variant called “stealth omicron?”
The nickname “stealth omicron” was created by researchers who found that a unique feature in this variant’s genetic sequence caused PCR test results to look different than those of other strains.
That means they were able to determine which variant someone had from the PCR test, which was a new concept. Previously, PCR tests were unable to show which COVID strain someone was infected with, only whether the virus had been detected.
However, a mutation of BA.2 does not have that difference in the genetic sequence that allowed researchers to mark a positive PCR test as BA.2 or not. So, it’s back to only knowing whether the patient tested positive for COVID and not knowing which variant the person has.
Is stealth omicron (BA.2) more contagious?
A Danish study showed that “people infected with the BA.2 subvariant were roughly 33% more likely to infect others, compared to those infected with BA.1.”
Across the globe, the original omicron variant (BA.1) accounts for the vast majority of COVID cases, but in Denmark BA.2 has become the dominant strain. And this shift is expected to happen around the world as stealth omicron becomes more widespread.
Will the COVID vaccine protect against BA.2?
Because this strain is so new and hasn’t hit the world at large yet, there is little information known about it.
However, the Danish study mentioned above showed that BA.2 is more “immune evasive” and is thus likely to infect vaccinated and boosted people. Despite these findings, vaccines and booster shots are still important as they may be able to decrease the chance of getting infected with this new variant, and may make transmission less likely as well.
Is BA.2 more dangerous than other variants?
Research is limited with this new variant since it has freshly emerged, however, so far there has been no evidence that shows BA.2 leading to more severe illness than previous strains of COVID. It is more contagious, but health officials in Denmark are saying that they have not seen a notable increase in hospitalizations or deaths with stealth omicron.
