- The delta Covid variant still accounts for an estimated 41.1% of cases in the U.S., the CDC said.
- The first known case of omicron in the U.S. was identified on December 1.
The Omicron variant was estimated to be 58.6% of the coronavirus variants circulating in the United States for the week ending December 25, according to data from the U.S. Centers for Disease Control and Prevention.
The fast-spreading variant was first detected in southern Africa and Hong Kong in November, with the first known case in the United States identified on December 1 in a fully vaccinated person who had traveled to South Africa.
The Delta variant accounts for 41.1% of all U.S. Covid-19 cases, according to the public health agency's data on Tuesday.
The agency said the data includes modeled projection that may differ from weighted estimates generated at later dates.