Omicron Subvariant BA.2.12.1 Poised To Become Dominant In U.S. This Week; Already Driving Covid Hospitalizations In New York

Omicron Subvariant BA.2.12.1 Poised To Become Dominant In U.S. This Week; Already Driving Covid Hospitalizations In New York

In the past few weeks, everyone from late night hosts to country stars to comedians to many at the White House, including Vice President Kamala Harris, has contracted Covid. The uptick in boldfaced names testing positive is not a coincidence.


Centers for Disease Control and Prevention data released today shows BA.2.12.1, thought to be 30% more infectious than BA.2, is poised to become the dominant variant in the United States.


Seven weeks ago, Americans got the news of what was then the latest in several waves of new Omicron variants, each more infectious than the rest. BA.2.12.1 is actually a subvariant of BA.2, which was at that point pushing out the original Omicron. Before March 19, BA.2.12.1 and sister subvariant BA.2.12.2 made up only 1.5% of newly-sequenced positive tests.

By last week, BA.2.12.1 had beaten out its sister sublineage for a 36.5% share of all newly-sequenced positive Covid tests. This week, that number has jumped to 42.6%, making it very likely that BA.2.12.1 will become the dominant variant in the country in the next 7-10 days.

ba-2-12-1-omicron-covid A chart showing the growth of BA.2.12.1 (in red) vs. BA.2 (in pink) CDC

In the region comprised of New York, New Jersey and Connecticut, where the subvariant was first identified, it is already tied to 66% of new cases sequenced. As of the past weekend, hospitalizations and deaths in New York were up 38% and 24%, respectively.


It’s important to note that BA.2 had already begun sending those numbers up before BA.2.12.1 took hold, but the new variant seems to be supercharging the increases in those important categories.


Across Pennsylvania, West Virginia and Virginia, BA.2.12.1 makes up 48% of new cases. The Southeast is close behind, with 45% of new infections now associated with the subvariant. See map below for a regional look at the U.S. updated today by the Centers for Disease Control and Prevention.

ba-2-12-1-covid-omicron A chart showing the share of BA.2.12.1 (in red) vs. BA.2 (in pink) in regions across the U.S. CDC

If there is good news in the new data, it’s that the next wave of Omicron variants — called BA.4 and BA.5 and thought to be even more transmissible than BA.2.12.1 — have not seen the same rate of spread in the U.S. since their arrival here on March 19. Their share remains minuscule, with only 19 cases detected Stateside since March 19.