COVID variant XBB accounts for more than 18% of U.S. cases

The Omicron subvariant XBB accounts for 18.3% of the COVID-19 cases in the United States for the week ended Dec. 24, up from 11.2% in the previous week, the U.S. Centers for Disease Control and Prevention said on Friday.

The XBB variant has been driving up cases in parts of Asia, including Singapore, and some experts have said it is more transmissible but less severe.