A new version of the Omicron variant has been spreading in countries around the world, but the strain, named BA.2, to date has not been labeled a variant of concern by the World Health Organization, and early research is showing that it behaves similarly to BA.1, the original Omicron variant of Covid-19.
BA.2 has been detected in the U.S., the U.K., Singapore, Sweden and the Philippines. In Denmark, where BA.2 has also been detected and is beginning to displace its sibling, BA.1, an initial analysis by the government-run State Serum Institute showed no differences in hospitalizations for BA.2 compared with BA.1, according to the Wall Street Journal.
According to the U.S. Centers for Disease Control and Prevention, in the U.S., where the Omicron strain is causing 99.9 percent of all cases, the BA.2 represented a small number of those cases and was included in the Omicron data. “Currently there is no evidence that the BA.2 lineage is more severe than the BA.1 lineage. [The] CDC continues to monitor variants that are circulating both domestically and internationally,” the CDC said.
Viruses mutate all the time, and it is common for variants to have multiple versions. According to Francois Balloux, director of the University College London Genetics Institute (via WSJ), the earlier Delta variant comprised more than 200 sublineages before it was replaced by Omicron. Omicron is the widely-spreading variant of Covid-19 that produces less severe illness, leading to reduced hospitalizations compared to the Delta variant before it.