(WASHINGTON) — President Donald Trump wasn’t expected to join Vice President Mike Pence and President-elect Joe Biden in the coming days when they get vaccinated for COVID-19, a decision that could be tied to the recommendation to wait 90 days after he received a certain treatment during his COVID-19 illness — but also one that hasn’t been fully explained to the public.

Trump has remained mostly absent from public view since the announcement that the nation’s first vaccine was to be distributed across the country. While he has repeatedly endorsed the benefit of vaccines in recent months, it remains an open question whether he will personally take it.

Trump, who is presumed to have some degree of immunity to the coronavirus after contracting it this fall, indicated this week he would not get vaccinated a vaccine anytime soon. But the Centers for Disease Control and Prevention recommends that even those who have recovered receive the vaccine.

While the White House cited his prior illness — as well as, it said, his desire not to jump ahead of healthcare workers and residents and workers in long-term care facilities, whom the CDC has recommended get inoculated first — it did not mention that a specific COVID-19 treatment he received in October, a monoclonal antibody cocktail, may place him in a category the CDC recommends should hold off.

In contrast, Pence and Biden planned to get inoculated publicly in the coming days.

The CDC recommended this month that the first available doses go to front-line health care workers and residents and workers in long-term care facilities, although it was ultimately up to state and regional leaders to decide how to distribute the limited supply of doses available so far. The defense department and several other federal government agencies received doses, too.

Public health officials and experts have argued it could be beneficial for public figures — including prominent politicians — to get jabbed before cameras, in order to convince Americans who remain skeptical about the COVID-19 vaccines, which are being produced in record time. One version was authorized for emergency use for the first time in the United States late last week.

Dr. Anthony Fauci, the federal government’s top infectious disease expert, said in an interview with ABC’s “Good Morning America” on Tuesday that he thought Biden and Vice President-elect Kamala Harris should also get vaccinated to protect national security.

“For security reasons, I really feel strongly that we should get them vaccinated as soon as we possibly can,” Fauci, the director of the National Institute of Allergy and Infectious Diseases, said. “You want him fully protected as he enters into the presidency in January. So that would be my strong recommendation.”

Fauci, who advises the current administration and also plans to serve as Biden’s chief medical adviser on the pandemic, said he thought Trump and Pence should get inoculated, too.

“If he were asking me, I would recommend that he do that, as well as Vice President Pence,” Fauci said in an interview with ABC News Chief Anchor George Stephanopoulos. “You still want to protect people who are, you know, very important to our country right now. Even though the president himself was infected and he has, likely, antibodies that likely would be protective, we’re not sure how long that protection lasts. So to be doubly sure, I would recommend that he get vaccinated, as well as the vice president.”

Trump’s unique position

Compared to Biden and Pence, Trump finds himself in a unique position after having fallen ill with the coronavirus. Those who have recovered are believed to have some level of protection, although the strength and length of such protection remains a subject of study, and the CDC recommends that even people who have tested positive for COVID-19 in the past get vaccinated.

Aside from his presumed immunity, Trump actually falls into a category of people for whom the CDC suggests delaying vaccination.

As part of his treatment for COVID-19 in early October, the president received a cocktail of monoclonal antibodies produced by the pharmaceutical company Regeneron; he became one of only roughly 10 people at the time who had gotten it outside of clinical trials.

The CDC recommends that those who received that treatment wait 90 days before getting vaccinated.

“Based on the estimated half-life of such therapies as well as evidence suggesting that reinfection is uncommon in the 90 days after initial infection,” CDC guidelines read, “vaccination should be deferred for at least 90 days, as a precautionary measure until additional information becomes available, to avoid interference of the antibody treatment with vaccine-induced immune responses.”

White House press secretary Kayleigh McEnany, though, did not cite that specific reason as a factor this week when she explained Trump’s decision to delay his inoculation, and the White House on Thursday did not respond to a question about whether it had played a role.

Instead, speaking to reporters at a news conference Tuesday, McEnany cited the immunity he was already believed to have from his illness and treatment.

And, she said, the president wanted to “set an example” by sending the message that “our long-term care facility residents and front-line workers are paramount in importance.”

Trump said Sunday that he had yet to be “scheduled” to get vaccinated.

“I am not scheduled to take the vaccine,” Trump tweeted, “but look forward to doing so at the appropriate time.”

Pences looking for maximum exposure, targeting skeptical Republicans

A Biden transition team official told ABC News that the president-elect was expected to receive the vaccine as soon as next week.

“It’s important that people who are in the greatest need get it,” Biden said last month. “I wouldn’t hesitate to get the vaccine. But I also want to set an example.”

Pence, the leader of the White House’s coronavirus task force, planned to get vaccinated before cameras on Friday alongside his wife, Karen, in order “to promote the safety and efficacy of the vaccine and build confidence among the American people,” according to the vice president’s office.

When recommending Pence get vaccinated, the vice president’s White House physician also considered the need to protect his health as a way of ensuring continuity of government, according to an official in Pence’s office.

While McEnany said Trump wanted “to make sure that the vulnerable get access first” — and that Trump was “very open to taking this, but wants to prioritize our front-line workers” — in announcing Pence’s plans, the vice president’s office did not address this concern.

His team has tried to maximize coverage of the shots — working with television networks to ensure live coverage on Friday — and, according to the official, including the second lady was aimed at convincing skeptical Republicans in particular.

In polls, Republicans have consistently been less willing to get the vaccine than Democrats or independents have been. The official said Karen Pence’s appearance could illustrate a familial element to making a decision to get vaccinated.

Surgeon General Jerome Adams planned to get jabbed alongside them, too. Adams, who is Black, has been outspoken at convincing the Black community — which has also expressed heightened skepticism — to get inoculated, and the official said Adams planned to double down on that message Friday.

Earlier this week, acting Defense Secretary Christopher Miller also got vaccinated publicly, in order to show military service members the vaccine was safe. West Virginia Gov. Jim Justice, too, got a shot before cameras.

While Trump briefly voiced support for vaccines on Twitter Thursday, he has remained out of public view during a historic week for the pandemic — marked by the beginning of mass inoculations and by record-high death tolls.

“The Vaccine and the Vaccine rollout are getting the best of reviews,” Trump tweeted Thursday morning. “Moving along really well. Get those ‘shots’ everyone!”

But otherwise, he has left the public encouragement to his deputies and the incoming administration.

Trump has maintained a light public schedule since losing reelection last month. Always focused on optics, Trump’s absence from view this week was notable considering he had for months been touting the benefits of vaccines.

He also has not commented on the record-high death tolls in recent days.

A daily high of 3,656 Americans were reported dead from COVID-19 on Wednesday, according to Johns Hopkins University.

ABC News’ Anne Flaherty and Molly Nagle contributed to this report.

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