The Omicron subvariant XBB.1.5 has likely become the dominant variant in the United States, accounting for 61.3% of COVID cases in the week ended Jan. 28, data from the U.S. Centers for Disease Control and Prevention showed on Friday.
The subvariant accounted for 49.5% of cases in the week ended Jan. 21, estimates from CDC showed.
XBB.1.5, which is currently the most transmissible variant, is an offshoot of XBB, first detected in October.
The now-dominant XBB-related subvariants are derived from the BA.2 version of Omicron.
An analysis from CDC showed on Wednesday that updated COVID-19 boosters from Pfizer Inc (PFE.N)/BioNTech SE and Moderna (MRNA.O) helped prevent symptomatic infections against the new XBB-related subvariants.