NEW YORK (AP) – Omicron has outpaced other options and is now the dominant version of the U.S. coronavirus, accounting for 73% of new infections last week, federal health officials said Monday.
Figures from the Centers for Disease Control and Prevention showed a nearly six-fold increase in the proportion of omicron infections in just one week.
In most of the country, it is even higher. Omicron is responsible for 90% or more of new infections in the New York City, Southeast, Industrial Midwest and Pacific Northwest area. More than 650,000 omicronic infections occurred in the United States last week, according to nationwide figures.
Since late June, the delta variant has been the main contagion in the United States. More recently, at the end of November, more than 99.5% of coronaviruses were delta-type, according to the CDC.
CDC director Dr Rochelle Walenski said the new numbers reflect growth seen in other countries.
“These numbers are amazing, but they are not surprising,” she said.
Scientists in Africa first sounded the alarm about the omicron less than a month ago, and on November 26, the World Health Organization identified it as “an option of concern.” Since then, the mutant has appeared in about 90 countries.
Much remains unknown about the omicron variant, including whether it causes more or less severe disease. Early research suggests that vaccinated individuals will need booster vaccinations to best prevent omicron contamination, but even without an additional dose, vaccination should provide reliable protection against serious illness and death.
“We all have a date with the omicron,” said Dr. Amesh Adala, senior fellow at the Johns Hopkins Center for Health Security. “If you are going to interact with society, if you have any lifestyle, you will be faced with an omicron, and the best way to deal with it is to get a full vaccination.”
Adalya said he was not surprised by the CDC data showing the omicron delta is overtaking in the US given what has been seen in South Africa, the UK and Denmark. He predicted the spread of the disease over the holidays, including breakthrough infections among the vaccinated and serious complications among the unvaccinated, which could cause stress in hospitals already burdened with delta.
Dr. Eric Topol, head of the Scripps Research Institute for Translational Research, said other countries saw rapid omicron growth, but the US data showed “a remarkable leap in such a short time.”
Poplar also said it’s unclear how much softer omicron actually is compared to other options. “This is a lot of uncertainty right now.”
CDC estimates are based on thousands of coronavirus samples collected each week from university and commercial laboratories, as well as state and local health departments. Scientists are analyzing their genetic sequences to determine which versions of the COVID-19 viruses are most common.
On Monday, the CDC revised its estimate of omicron cases for the week ending December 11 after analyzing additional samples. About 13% of cases this week were due to the omicron, rather than the 3% previously reported. A week earlier, omicron accounted for just 0.4% of cases.
CDC officials said they did not yet have estimates of how many hospitalizations or deaths were due to the omicron.
Although there are many new infections with the delta variant, “I expect that over time this delta will be supplanted by the omicron,” Walensky said.
Associated Press contributors Laurent Niergaard and Karla C. Johnson contributed to this report.
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