LOS ANGELES, Jan. 10 (Xinhua) -- New Omicron subvariant XBB.1.5 is spreading quickly in the United States, and is estimated to account for nearly 30 percent of COVID-19 cases in the United States in the week ending Jan. 7, according to the latest data of the U.S. Centers for Disease Control and Prevention (CDC).

XBB.1.5 is projected to comprise more than 70 percent of viruses in some northwestern regions in the country, CDC data showed.

XBB.1.5 made up 27.6 percent of the total cases in the week ending Jan. 7, rising from 18.3 percent from a week before and 11.5 percent two weeks prior, according to the CDC.

The XBB variant has been driving up cases in parts of Asia, drawing concerns for its high infectiousness.

Another two dominant Omicron subvariants BQ.1 and BQ.1.1 accounted for about 55 percent of new COVID-19 cases in the United States in the latest week, CDC data showed.