Scientists are now closely monitoring a new mutation of the omicron variant of the coronavirus, the World Health Organization confirmed Wednesday.
With omicron swarming the world, officials have identified BA.2. as an offshoot of that highly transmissible variant.
It is not yet a “variant of concern,” WHO officials said. However, BA.2 numbers reportedly are rising, with at least 40 countries adding cases to a global variant tracking database.
The subvariant has spread rapidly in Denmark and the United Kingdom, with almost half of recent cases in Denmark attributed to BA.2.
Health officials reported that the subvariant has arrived in America, with two confirmed cases in Washington state.
Overall, more than 8,000 cases of BA.2 have been found, but its origin remains undetermined.
“It is the nature of viruses to evolve and mutate, so it’s to be expected that we will continue to see new variants emerge as the pandemic goes on,” Dr. Meera Chand, the COVID-19 incident director at the UK Health Security Agency, said in a statement. “So far, there is insufficient evidence to determine whether BA.2 causes more severe illness than Omicron BA.1, but data is limited.”
Officials have pointed out that most variants, like delta and omicron, have subvariants.
“Conventional COVID-19 tests can show a positive or a negative result, but they can’t determine specific variants. For that, scientists need to do additional genetic sequencing,” Dr. Nitya Rajeshumi, a pediatrics resident at the Children’s Hospital of Philadelphia, wrote for ABC News.
“Conveniently, the omicron variant has a particular genetic signature that allows scientists to quickly and easily determine if the sample is omicron or not,” Rajeshumi wrote.
The new BA.2 subvariant does not have that feature, meaning scientists can no longer use this shortcut, though they can still identify the subvariant using genetic sequencing technology, Rajeshumi said.
Because of this, the BA.2 subvariant has sometimes been referred to as the “stealth” variant. But for the general public, conventional COVID-19 tests will still work to detect the new subvariant.
“While it’s important to understand that in the family of omicron, there is a sub-lineage that is potentially more transmissible, it’s not necessarily a cause for panic,” Dr. John Brownstein, chief innovation officer at Harvard University’s Boston Children’s Hospital, told Rajeshumi.