Omicron has now become the dominant coronavirus variant in the United States, overtaking delta in mere weeks, according to new CDC data. To fight the surge, the Biden administration will announce a new plan to aid overwhelmed hospitals and increase both vaccination and testing capacity.

The policies Biden and states could use to control the omicron variant

Omicron becomes dominant in the U.S.

CDC on Monday announced that the omicron variant now accounts for an estimated 73.2% of U.S. Covid-19 cases identified between Dec. 12 and Dec. 18—a dramatic increase from the week before when omicron accounted for just 12.6% of cases.

The omicron variant: The 'good,' 'bad,' and 'ugly' scenarios

The prevalence of omicron is even higher in some parts of the country, NPR reports, including the Pacific Northwest, the Great Lakes, the Southeast, New England, and Texas. In these areas, omicron is estimated to make up more than 90% of all positive Covid-19 cases that have been sampled.

According to CDC Director Rochelle Walensky, the rapid rise of omicron in the United States is similar to the growth seen in other countries. "These numbers are stark, but they're not surprising," she said.

Similarly, Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security, said he was not surprised omicron overtook delta in the United States, especially given its similar growth trajectory in South Africa, the United Kingdom, and Denmark. He also predicted that omicron would spread significantly over the holidays, leading to more breakthrough infections among the vaccinated and potentially severe illness among the unvaccinated.

"All of us have a date with omicron," Adalja said. "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."

It remains unclear whether omicron is inherently milder than other coronavirus variants, but several health experts have warned that, even if omicron only rarely causes severe symptoms, the variant could still infect so many people so rapidly that it overwhelms hospitals.

"That's the big concern," said Marcus Plescia, CMO for the Association of State and Territorial Health Officials. "If there are a lot of people getting sick, even if only a small portion of them are getting severely ill, that could still be a huge number of people."

Biden's plan to fight omicron

President Joe Biden on Tuesday is expected to announce new measures to help combat an impending omicron surge—representing a significant escalation in the White House's previously announced plans to fight the coronavirus this winter.

The Federal Emergency Management Agency (FEMA) will also deploy planning officials to assist with hospital capacity and coordinate necessary supplies, such as masks, gloves, and ventilators. To expand vaccination capacity, FEMA will stand up several pop-up vaccination clinics across the country, including mobile units in Washington, D.C., and New Mexico.

Further, the government intends to increase testing capacity through several measures. According to the New York Times, several new federal testing sites will be opened, beginning with sites in New York City that will be running before Christmas.

The government also plans to purchase 500 million rapid Covid-19 tests and distribute them free of charge to the public. These rapid tests will not be available until January, senior administration officials said, but when they are, people will be able to request them through a website and have them sent to their homes.

According to Leana Wen, an emergency physician and professor of health policy and management at George Washington University, 500 million tests is "impressive sounding," but "does not come even close to what is needed."

Instead, Wen said the government needs to provide enough tests "for all American families to be able to test twice a week, every week."

"It needs to become the norm to test before going to school and work, and before families and friends have dinner together," she added. (Leonard, Politico, 12/20; Reyes, Axios, 12/20; AP/Modern Healthcare, 12/20; Franklin, NPR, 12/20; Branswell, STAT News, 12/20; Stolberg, New York Times, 12/21; Facher, STAT News, 12/21; Diaz, NPR, 12/21)