New Omicron Subvariant Raises Questions About Pandemic’s Future
A new twist on the omicron coronavirus variant has some researchers concerned about the next development in the global pandemic.
Known as subvariant BA.2, the new version of omicron is about 1.5 times more infectious than the original omicron variant (BA.1), according to the Statens Serum Institut of Denmark, where the subvariant is surging and makes up half of all omicron cases.
South Africa, which first reported the omicron variant in late 2021, is now tracking a sharp increase in the BA.2 subvariant. The subvariant has also been identified in Botswana, Kenya, Malawi and Senegal.
It’s unclear where BA.2 emerged first, but it was found in genetic material submitted to the global COVID-19 database by researchers in the Philippines.
According to researchers, the BA.2 subvariant has five mutations on its spike proteins that make invading cells easier, making the virus more transmissible. At the same time, it is missing a mutation that researchers use to distinguish omicron from other variants, making the subvariant more difficult to identify in gene-based polymerase chain reaction testing.
“We’re a bit concerned that we may have missed some of this BA.2 in some of the samples that we’ve screened previously,” said Dr. Nicksy Gumede-Moeletsi, senior virologist at the World Health Organization’s Africa regional office, during a recent news briefing.
Because of that missing mutation, researchers are calling BA.2 the “stealth” version of omicron.
Experts say the creation of subvariants is a normal part of viral evolution. The more often a virus replicates, the more chances it has to create a variant that can spread and possibly escape immunity.
The delta variant, for example, created more than 200 subvariants before omicron arose. Researchers believe omicron has split into four subvariants, which will continue to change. The third subvariant, BA.3, has turned up in fewer than 400 cases worldwide, according to researchers.
“We are watching this virus evolve in real time,” WHO epidemiologist Maria van Kerkhove said during a recent briefing on omicron.
Omicron infections are milder than previous variants, with a lower risk of hospitalization. Being infected with either the BA.1 or BA.2 versions of omicron creates immunity to the other, according to Professor Francois Balloux, director of the University College London’s Genetics Institute.
So far, the BA.2 subvariant has shown no signs of getting around the body’s immune system.
“Very early observations from India and Denmark suggest there is no dramatic difference in severity compared to BA.1,” Tom Peacock, a virologist at Imperial College, London, posted on Twitter. “Personally, I’m not sure BA.2 is going to have a substantial impact on the current omicron wave of the pandemic.”