Publisher Health

WASHINGTON — President Biden on Thursday said he was directing his staff to purchase an additional 500 million coronavirus tests for distribution to Americans, doubling the government’s previous purchase as his administration scrambles to respond to the highly contagious Omicron variant.

The announcement, which came when Mr. Biden delivered remarks on the pandemic, brings to one billion the total number of tests to be given away free of charge.

“That will mean a billion tests in total to meet future demand,” Mr. Biden said. “And we’ll continue to work with the retailers and online retailers to increase availability.”

But it is unclear when the tests will be available. Mr. Biden announced the first batch of 500 million tests just before Christmas, and the first batch from that announcement will not start being delivered until later this month, according to White House officials. Details about how Americans can request those tests, including a government-run test website, are slated to be unveiled on Friday.

The president did not say when the new batch of 500 million tests will be manufactured and ready for distribution. But he said the at-home tests — along with more than 20,000 testing sites around the country — will help to meet the surging demand as people try to continue work, school and social life despite the rapid spread of the virus.

“We’re on track to roll out a website next week where you can order free test shipped to your home,” he said, adding that people with medical insurance can also soon get reimbursed for the purchase of up to eight tests a month.

Mr. Biden said his administration will also be announcing a plan next week to ensure that Americans have access to high-quality masks. Experts have said that KN95 and N95 masks protect better against the Omicron variant than the more common cloth or surgical masks.

He did not provide any details about that effort during his remarks.

The announcement about tests comes as the president also announced on Thursday that the administration is sending a total of 120 military medical personnel to six states, the beginning of a deployment of 1,000 service members to help hospitals deal with a surge in cases from the Omicron variant, White House officials said.

Mr. Biden appeared alongside Lloyd J. Austin III, the defense secretary, and Deanne Criswell, the director of the Federal Emergency Management Agency, at the White House to detail the teams heading to hard-hit communities across the country. Mr. Biden said late last month that he would be tapping the military to help hospitals early in January.

Officials said the new teams of doctors, nurses and other medical personnel would begin arriving at hospitals in Michigan, New Jersey, New Mexico, New York, Ohio and Rhode Island. They said the teams would help triage patients arriving at hospitals, allowing short-staffed emergency departments to free up space.

The deployments are part of the Biden administration’s efforts to tackle the latest surge of cases caused by the highly contagious Omicron variant. As it has surged, so have new cases, reaching more than 780,000 a day across the country. The number of Americans hospitalized with Covid-19 has hit a record high of about 142,000.

For Mr. Biden, the inability to get control of the pandemic has helped drag down his approval ratings as he enters his second year in office. His aides are intent on publicly communicating their efforts to deal with the virus.

Since Thanksgiving, when Omicron was first discovered in South Africa, the administration has sent over 800 military and emergency personnel to 24 states, tribes and territories, officials said, not counting the personnel Mr. Biden announced on Thursday.

In addition, more than 14,000 National Guard members have been activated in 49 states to help at hospitals with vaccinations, testing and other medical services, officials said. Those deployments have been paid for by the American Rescue Plan, a law that Mr. Biden championed at the beginning of his term.

“To the military medical teams on the ground, thank you for all everything you’re doing,” the president said.

Officials said there would likely be further deployments of military medical personnel in the days ahead as the country continues to struggle with the pandemic.