WASHINGTON – President Donald Trump berated his own Cabinet on Thursday for not prosecuting or implicating his political enemies, lashing out amid a cascade of daunting poll numbers and a bout with the coronavirus that has locked him in the White House just weeks before the election.

In his first extended public comments since learning he had the virus last week, Trump balked at participating in holding the next debate with his Democratic challenger, former Vice President Joe Biden, remotely for health reasons and called Sen. Kamala Harris, Biden’s running mate, a “monster” and a “communist.”

The president castigated his own team as well, declaring that Attorney General William Barr would go down in history “as a very sad, sad situation” if he does not indict Democrats like Biden and former President Barack Obama. He complained that Secretary of State Mike Pompeo had not released Hillary Clinton’s e-mails, saying, “I’m not happy about him for that reason.” And he targeted Christopher Wray, the FBI director. “He’s been disappointing,” Trump said.

The president’s comments in an hourlong telephone interview with Fox Business in the morning came during what even for him was a scattershot performance, one that advisers said reflected increasing frustration over his political fortunes only 26 days before an election with surveys that show him trailing Biden by double digits.

He was all over the map, throwing out unsubstantiated or discredited accusations, explaining that he wanted to bring home troops from Afghanistan to be ready to fight China or Russia if necessary and calling Gov. Gretchen Whitmer of Michigan “the lockup queen” even as his own Justice Department was announcing the existence of an anti-government group’s plot to kidnap her.

As for his opponents, he said that Biden “wouldn’t be president for two months” because “he’s not mentally capable,” leaving Harris to then take over the presidency. “She’s a communist,” he said. “We’re going to have a communist.” A few hours later, Trump reposted Twitter messages claiming that House Speaker Nancy Pelosi might be orchestrating “a coup” against him.

But it was his assault on his own appointees that hinted at the escalating imperative to change the course of a campaign that has defied his efforts to shape it for months, what amounted to a plea for an October surprise.

“Unless Bill Barr indicts these people for crimes, the greatest political crime in the history of our country, then we’re going to get little satisfaction unless I win and we’ll just have to go, because I won’t forget it,” Trump said, referring to the investigation into his 2016 campaign ties with Russia. “But these people should be indicted. This was the greatest political crime in the history of our country, and that includes Obama and it includes Biden.”

Trump has often argued that his political antagonists should be prosecuted, but in this case, he went further by indicating that he had directly pressured Barr to indict without waiting for more evidence. “He’s got all the information he needs,” the president said. “They want to get more, more, more, they keep getting more. I said, ‘You don’t need any more.’ ”

Even as he sought to reassert himself on the public stage after a week in the hospital and in the White House infected with the coronavirus, Trump brushed off the disease, saying that “when you catch it, you get better,” ignoring the more than 212,000 people who have died from it in the United States. He even seemed to suggest he may have been infected by the Gold Star parents of soldiers killed in battle at an event honoring them last month at the White House, although a spokesman later denied he meant that.

Fellow Republicans exhibited increasing frustration with the president’s casual approach to the virus that has now infected not just himself and the first lady but two dozen other high-ranking officials, campaign aides, advisers and GOP senators who attended White House events.

Pelosi said she planned to introduce legislation Friday creating a commission on presidential capacity to review the health of a commander in chief under provisions of the 25th Amendment providing for the temporary transfer of power to the vice president in case of inability to discharge the duties of the office. “Crazy Nancy is the one who should be under observation,” Trump replied on Twitter.

The president’s phone interview with Maria Bartiromo of Fox Business was his first time answering questions since he was infected with the virus. He insisted that he had recovered and was no longer taking the experimental drugs used to treat the virus, but that he was still taking a steroid that doctors say can produce bursts of energy, euphoria and even a sense of invulnerability.

“I felt pretty lousy,” Trump said. But, he added, “I’m back because I’m a perfect physical specimen and I’m extremely young.” He once again played down the severity of the disease. “Now what happens is you get better,” he said. “That’s what happens, you get better.”

White House aides privately expressed concern about whether the president’s animated mood in recent days stemmed from the dexamethasone steroid he is on. Doctors not involved with the president’s care said it could have a significant effect on a patient’s behavior.

Dr. Negin Hajizadeh, a pulmonary/critical care physician at Northwell Health, noted that the majority of COVID patients receiving dexamethasone are on mechanical ventilation and in a state of induced coma, so they do not exhibit any behavioral side effects. But, she said, large studies show that generally 28-30% of patients will exhibit mild to moderate psychiatric side effects like anxiety, insomnia, mania or delirium after receiving steroid treatments, and about 6% may develop psychosis.

“When we prescribe steroids we warn our patients: ‘This may cause you to feel jittery, might cause you to feel irritable,’ ” Hajizadeh said. “We will tell family members, especially for our older patients, ‘This may cause insomnia, this may cause changes in eating habits and, in extreme cases, mania and impaired decisionmaking.’ ”