As communities across the country desperately seek access to emerging rapid-turnaround covid-19 tests, one place already using them is the White House, where guests visiting President Trump and Vice President Pence have been required to undergo the exams since last week.

The procedure is the latest of new safeguards aimed at protecting the health of the nation’s top elected officials from the novel coronavirus, which has sickened some prominent global leaders. Among them is British Prime Minister Boris Johnson, a Trump ally, who was moved to intensive care this week in a London hospital due to complications of the illness.

White House visitors said they have been administered the test developed by Abbott Laboratories at the Eisenhower Executive Office Building, the complex across the street from the West Wing where Pence has an office and the staff of the National Security Council is based.

Abbott, which is producing 50,000 tests per day, began shipping supplies to the White House last week, though a spokesman for the company declined to say how many of the kits were sent.

During remarks Tuesday, Trump touted the Abbott test as a boon for hospitals that will be receiving the kits.

“It’s a five-minute test so people can get their results back very quickly,” he said.

One recent visitor to the White House described his experience, saying a nurse swabbed both of his nostrils in less than a minute and inserted them into the Abbott machine for an assessment. This person noticed administration officials, including a couple Cabinet members, waiting to get tested, and he was told that every visitor meeting the president would get a test, even if they felt healthy.

The White House medical office indicated it would contact the person within 15 minutes if the test came up positive, and he was cleared after that duration to proceed to his meeting with Trump, said the visitor, who spoke on the condition of anonymity to discuss a private process. An Abbott spokesman said the test can deliver a positive result within five minutes and a negative result in 13 minutes.

“I learned the day before I was coming that we were getting tested,” the White House visitor said.

The new requirement began last week, and a group of energy company officials, including the chief executives of Exxon Mobil and Chevron, were tested before their meeting with the president and several U.S. senators in the Cabinet Room on Friday.

A number of senior White House staffers have received emails directing them to schedule tests in the EEOB because of their “proximity” to the vice president and president, according to an email reviewed by The Washington Post. Dozens of aides have been tested so far.

One senior administration official who was tested last week said the plan was for “core officials” around the president to be tested weekly. During a recent news briefing at the White House, Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, told reporters he had been tested two days earlier, and Trump said he underwent a second test last week. Both men said their tests were negative. Pence also said he tested negative for the virus.

White House aides described the testing requirements as an additional layer of security that builds on steps already implemented: to cancel public tours; take the temperature of all those who enter the complex, including reporters; encourage remote work; and shut down services in the EEOB, including a dry cleaning service, the gym and the library. Trump has been conducting meetings via video conference, including with small business executives on Tuesday.

Meantime, the National Security Council has moved to reduce the number of people in the EEOB, working in shifts, with more than half the staff at home each week, according to people with knowledge of the situation. Senior directors at the agency no longer attend briefings with Trump at the White House, leaving that to national security adviser Robert O’Brien and his deputy, Matthew Pottinger.

“The President’s physician and White House Operations have been working closely to ensure every precaution is taken to keep the President, first family and the entire White House Complex safe and healthy at all times, including most recently beginning to test all those in proximity to the president and vice president for covid-19,” White House spokesman Judd Deere said in a statement.

The move to testing has come after Trump initially spent weeks dismissing the threat from the coronavirus, which has been confirmed to have infected more than 393,000 people and killed more than 12,000 in the United States.

And Trump has continued to flout guidance from medical experts, saying he won’t wear a face mask even though the Centers for Disease Control and Prevention formally recommended that all Americans wear them in public to help prevent spreading the virus. Trump also joked when asked by a reporter why he does not cut off in-person contact with Pence to ensure the continuity of government that could be severely disrupted if they both were to contract the virus.

“I get next to him, I don’t breathe,” Trump said Sunday, before adding he was “only kidding.” Asked again Monday, Trump suggested the ease of the new Abbott test would allow him and his aides feel more secure.

“Mike had his test a couple of days ago; I had my test a couple of days ago so and we are here,” Trump said. “Just because of questions like that, I think we will probably have maybe quite a few tests. It is not the worst idea. You know the system of testing now is so quick and so easy.”

Global health experts cheered the move to implement stricter screening protocols at the White House, saying it would be virtually impossible to completely isolate Trump and Pence. Limiting the number of visitors and testing them is an important step to limit the risk of exposure, they said.

“He is not going to just exist in isolation. That’s just not feasible,” said Stephen Morrison, a global health policy analyst at the Center for Strategic and International Studies. “But you can be smart about it. They’re trying to get smart now — that’s a good thing. And thank god they’ve gotten a rapid test that they feel confident about — that’s a huge breakthrough. The bigger meaning is that this is the future for all of us.”

Yet experts emphasized that no virus test is 100 percent reliable. Abbott’s covid-19 tests were approved by the Food and Drug Administration under an emergency authorization and company officials have not publicly disclosed their accuracy rates, which are still begin assessed as more people undergo the tests.

Company officials said the product is designed as a molecular test that uses a process based on well-established products on the market to detect the flu and other viruses.

White House aides have begun taking other precautions, as well. Deborah Birx, the response coordinator for the White House coronavirus task force, said Monday that over the weekend she chose not to visit her 10-month-old granddaughter who developed a high fever, over fears that she could potentially be exposed to the coronavirus.

Though the girl was later found not to have the illness, Birx said, given her own daily proximity to Trump and Pence, “you can’t take that kind of risk with the leaders of the country.”

Anxiety runs high throughout the building. During a recent Situation Room meeting, Larry Kudlow, the president’s chief economic adviser, sneezed loudly, startling many in the room. Some looked visibly uncomfortable with the sneeze.

Trump assured the room that Kudlow had been tested Friday and was negative for the coronavirus.