The new COVID-19 variant that scientists call JN.1 now makes up about 44.1% of COVID-19 cases across the country, the Centers for Disease Control and Prevention estimated Friday, marking another week of the fast-spreading variant’s steep rise in the U.S.

The increase is more than two times larger than the 21.3% that the CDC now estimates the strain made up of infections for the week ending Dec. 9, after Thanksgiving.