- A map shows how BA.2 has outcompeted other types of Omicron in the northeastern US.
- The subvariant has driven a new surge of cases in Europe.
- Experts warn a wave could soon reach the US, though some say that wave could be only mild.
The Omicron BA.2 subvariant has become dominant over other COVID-19 coronavirus variants in the northeastern US, per the latest CDC data.
The news comes as a surge of new cases in Europe, driven by the more-contagious BA.2 and by countries lifting COVID-19 restrictions. That surge is prompting some experts to worry that another wave could soon be coming to the US.
Experts told previously Insider they expect a wave of BA.2 in the US could be milder than in Europe, in part because of previous exposure to its cousin, the subvariant BA.1. More vulnerable groups could still be at risk, the experts said.
As of last week, BA.2 made up 55.4% of samples collected in Health & Human Services (HHS) Region 1, the CDC said Tuesday. This region covers Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont, as well as ten federally recognized Tribal Nations.
BA.2 also made up 51.8% of samples in HHS Region 2, which covers New Jersey, New York, Puerto Rico, and the US Virgin Islands.
The rest of the coronavirus samples cases were made up of other subtypes of Omicron.
According to estimates from the CDC, the subvariant already makes up about 35% of all cases in the US.
BA.2 is thought to be more contagious than BA.1, the subvariant of Omicron which is still dominant worldwide. However, it is not thought to be more dangerous than other Omicron variants.
It is not yet clear whether BA.2 will cause a huge surge of cases in the US, Insider previously reported.