(NEW YORK) — Omicron has raced ahead of other variants and is now the dominant version of the coronavirus in the U.S., accounting for 73% 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, it’s even higher. Omicron accounts for 90% to 10% of all new infections in New York, the Southeast and the Industrial Midwest. Nationally, there were more than 650,000 cases of omicron infection in the U.S. during last week.
The main variant causing U.S. infection was the delta version since June. According to CDC data, delta was responsible for more than 99.5 percent of all coronavirus infections as of the end November.
According to Dr. Rochelle Walensky, Director of the CDC, the numbers are representative of the growth 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.
Many details about the Omicron variant remain unknown. This includes whether or not it can cause more severe illnesses. Although early studies indicate that booster shots are necessary to prevent omicron infections, there is no doubt that vaccination will provide strong protection from severe illnesses and death.
“All of us have a date with omicron,” said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security. “If you’re going to interact with society, if you’re going to have any type of life, omicron will be something you encounter, and the best way you can encounter this is to be fully vaccinated.”
Adalja stated that he wasn’t surprised to see omicron surpassing delta in the U.S. CDC data, considering what had been seen in South Africa and the U.K. as well as Denmark. He expected spread of the virus over the holidays. Adalja said he was not surprised by the number of breakthrough infections in the immunized and severe complications in the unimmunized that could strain hospitals already overwhelmed with delta.
Dr. Eric Topol, head of the Scripps Research Translational Institute, said other countries had seen omicron’s fast growth, but the U.S. data showed “a remarkable jump in such a short time.”
Topol also said it’s unclear how much milder omicron really is compared with other variants.
“That’s the big uncertainty now,” Topol said. “We have to count on it being a lot of hospitalizations and a lot severe disease from omicron.”
CDC’s estimates are based on thousands of coronavirus specimens collected each week through university and commercial laboratories and state and local health departments. Scientists examine their genetic sequences in order to identify which COVID-19 versions are the most common.
After analyzing additional samples, the CDC updated its estimates for omicron-related cases in the week ending Dec. 11. The CDC reported that 13% of cases in the week ended Dec. 11 were caused by omicron. This is compared to the previously reported 3%. Omicron was only 0.4% in the previous week.
Officials from the CDC stated that it is not possible to estimate how many people have died or were hospitalized due to omicron.
Though there remain a lot of new infections caused by the delta variant, “I anticipate that over time that delta will be crowded out by omicron,” Walensky said.
This report was contributed by Carla K. Johnson and Laura Neergaard, both Associated Press reporters.