The United States passed five million Covid-19 cases on Sunday after adding one million new cases in just over two weeks, data from Johns Hopkins University showed.
The US, which has the worst outbreak of any country, recorded a total of 4 million cases on July 23 amid a surging outbreak in the south-east and south-west, and political battles over the Trump government's response to the pandemic.
The daily numbers were down from recent peaks, with 56,070 cases reported on Saturday, a 1.1 per cent increase on the previous day. Total deaths are 162,441, the data showed.
Democratic presidential candidate Joe Biden said the grim 5 million milestone "breaks the heart".
“It’s a number that boggles the mind and breaks the heart,” Mr Biden wrote on the Medium website at the weekend.
“Five million is more than the entire population of Alabama – or of more than half the states in our union, for that matter.
"Each time the number clicks up, it represents a life altered, a family stricken with anxiety, a community on edge.
"And for the families of the more than 160,000 souls who have died because of this virus, it is a pain that can never be undone.”
Mr Biden criticised President Donald Trump’s handling of the pandemic as the two prepared to compete in November’s elections.
“And yet, we continue to hear little more from President Trump than excuses and lies in an effort to cover for his repeated failures of leadership – failures that worsened the pandemic here at home and in turn deepened our economic crisis," Mr Biden wrote.
White House economic adviser Larry Kudlow on Sunday said the US was making inroads against the virus’s spread.
“Having gone through a very tough period as the virus spread to the south and west, it looks like we’re making pretty good progress,” Mr Kudlow told ABC.
“Am I worried in general? Yes, I’m always worried in general. Things have happened here that no one expected to happen – exponentially.”
Meanwhile, The Washington Post reported that an internal model by the White House's Council of Economic Advisers is projecting a rise in infections in August and into September and October, in the Midwest and elsewhere.
Mr Kudlow said he had “not heard anything about” that analysis.
Cases and deaths slowed in Florida and Arizona, two badly hit states.
Florida added 6,229 cases, a 1.2 per cent rise compared with the 1.4 per cent average daily increase over the previous week. Total cases are now 532,806.
Deaths among the state's residents also slowed, to 77 from 182 the day before. The state's death toll is now 8,186.
Arizona reported 816 cases, its lowest since late June. The 0.4 per cent increase was below the 0.7 per cent daily average increase of the previous week. Total cases are now 186,923.
The state, which medical experts including Anthony Fauci say appears to be turning a corner in its outbreak, reported 13 deaths, down from 56 the previous day. The death toll is now 4,150.
New York reported a 0.1 per cent rise in cases to 515, below the 0.2 per cent average daily increase from the previous week.
The state reported seven deaths, according to a tweet from Governor Andrew Cuomo.
Mr Cuomo said the 0.78 per cent rate of positive tests was the “lowest we have seen since the pandemic began".
The number of people admitted to hospital remained steady.
Former Food and Drug Administration commissioner Scott Gottlieb said the US appeared to be headed for a surge in rural regions after the virus hit urban areas.
“We’re probably going to have another wave,” Mr Gottlieb told CBS on Sunday.
He said there was concern about largely untouched rural communities, which were “probably a bit more complacent” about virus risks.
Rural spread is “going to be far more difficult to control if it’s more widespread", Mr Gottlieb said.
“We’re seeing indications of that right now, the wave spreading in the Midwest and the West.”