Omicron now dominant COVID-19 variant in U.S., makes up 73% of cases

The Centers for Disease Control and Prevention numbers showed nearly a six-fold increase in omicron's share of infections in only one week.

Omicron has raced ahead of other variants and is now the dominant version of the coronavirus in the U.S., accounting for 73 per cent of new infections last week, federal health officials said Monday.

The Centers for Disease Control and Prevention numbers showed nearly a six-fold increase in omicron’s share of infections in only one week.

In much of the country, omicron’s prevalence is even higher. It’s responsible for an estimated 90 per cent of new infections in the New York area, the Southeast, the industrial Midwest and the Pacific Northwest. The national rate suggests that more than 650,000 omicron infections occurred in the U.S. last week.

Since the end of June, the delta variant had been the main version causing U.S. infections. As recently as the end of November, more than 99.5 per cent of coronaviruses were delta, according to CDC data.

CDC Director Dr. Rochelle Walensky said the new numbers reflect the kind of growth seen in other countries.

“These numbers are stark, but they’re not surprising,” she said.

Scientists in Africa first sounded the alarm about omicron less than a month ago and on Nov. 26 the World Health Organization designated it as a “variant of concern.” The mutant has since shown up in about 90 countries.

Much about the omicron variant remains unknown, including whether it causes more or less severe illness. Early studies suggest the vaccinated will need a booster shot for the best chance at preventing omicron infection but even without the extra dose, vaccination still should offer strong protection against severe illness and death.