US presidential challenger Joe Biden on Sunday accused Donald Trump of giving up in the fight against Covid-19 as the president faced a new outbreak in his team, surging infections nationwide and an uncomfortable admission by his chief of staff.

Nine days before the vote -- and with reported US coronavirus deaths having surpassed the grim total of 225,000 -- Trump's chief of staff Mark Meadows conceded Sunday that "we are not going to control the pandemic, which he said could only be done through "vaccines, therapeutics and other mitigation areas."

Control was not practical, he said, because "it is a contagious virus just like the flu."

Biden immediately seized on Meadows' comment as he again hammered the administration over the virus, which has set records for new cases in recent days, with nearly 90,000 on Saturday.

"It was a candid acknowledgement of what President Trump's strategy has clearly been from the beginning of this crisis: to wave the white flag of defeat and hope that by ignoring it, the virus would simply go away," the former vice president said in a statement.

"It hasn't, and it won't."

Trump on Sunday was continuing a furious pace of campaigning for a second term in the White House, with stops in New Hampshire and Maine.

His repeated efforts to downplay the severity of the pandemic or shift voters' attention elsewhere has been met with the constant drip of bad news about the virus.

The latest example was Vice President Mike Pence's chief of staff Marc Short, and reportedly several of his aides, testing positive for Covid, swelling the list of administration staff to have caught the virus.

'Greatest failure'

Campaign spokesman Tim Murtaugh said Sunday that Pence would continue, with doctors' approval, to criss-cross the country in the waning days of the campaign. Both Pence and his wife had tested negative, he said.

"The folks on his staff are in quarantine, and he relies on the very sound medical advice of the White House medical unit," Murtaugh told Fox News.

The decision by Pence, who heads the White House coronavirus task force, to ignore standing advice from health experts to quarantine himself drew fire from Biden running mate Kamala Harris, who also criticized Meadows for likening the coronavirus to the flu.

"This is the greatest failure of any presidential administration in the history of America," she said.

On Sunday, Trump sought once again to brush aside the crush of bad Covid news, telling supporters in New Hampshire.

"We are coming around, we are rounding the turn, we have the vaccines, we have everything, we are rounding the turn. Even without the vaccines, we are rounding the turn."

No vaccines have yet been approved for the virus, and health experts are warning of thousands more deaths in the months ahead.

Trump and his aides have repeatedly attacked Biden's energy levels and what they say is his thin record of accomplishments.

Murtaugh slammed Biden for his light campaign schedule, saying the Democratic challenger was "feeling the heat" and "took five out of six days off" before the last presidential debate on Thursday.

The remarks drew a contrast to the frenetic pace that Trump, 74, has maintained, while Biden has set a more cautious course, speaking less frequently and to smaller, socially distanced groups.

Biden, 77, planned on Sunday only to take part in a virtual concert, his campaign said.

But his deputy campaign manager vigorously defended him, telling NBC's "Meet the Press," that "we are campaigning incredibly hard."

"The difference between what we're doing and what Donald Trump is doing," said Kate Bedingfield, is that "we're doing it safely."

Ahead of the November 3 election -- and with more than 57 million Americans having cast early votes -- both campaigns are scrambling to make their closing arguments.

On Saturday, an energized Biden and former president Barack Obama accused Trump of massively mishandling the pandemic.

"Donald Trump isn't suddenly going to protect all of us. He can't even take the basic steps to protect himself," Obama said, referring to Trump's hospitalization for Covid-19 three weeks ago.

But the president has continued to project confidence.

Insisting he will be the better steward of the nation's economy, he told supporters in North Carolina, "This election is a choice between a Trump super-recovery and a Biden depression."

Grim polls for Trump

"Covid, covid, covid," Trump said on Saturday, complaining that the media was fixated on the problem.

Biden's response: Trump himself should be more fixated on the problem.

"Donald Trump said, and is still saying, 'It's going away. We're learning how to live with it,'" Biden said Saturday in his native Pennsylvania, a critical swing state.

"We're not learning how to live with it. You're asking us to learn how to die with it."

Biden has maintained a stable lead of around 10 points in national polls, and narrower leads in battleground states.
But both Republicans and Democrats are wary of polling after the stunning upset Trump pulled off in 2016 when he defeated Hillary Clinton.