Biden called on governors of all 50 states to "institute a mask mandate nationwide, starting immediately" as a way to halt the virus's spread and save tens of thousands of lives.
"Look, this is America. Be a patriot," Biden, with his newly named running mate Kamala Harris nearby and wearing a face covering, told reporters near his home in Delaware.
"Protect your fellow citizens, step up, do the right thing," Biden added.
Most scientists and health experts agree that, absent a vaccine, wearing a mask and maintaining social distance are two easy steps people can take to slow the spread of a pandemic that has already infected 20 million people and killed 750,000 worldwide.
Even as COVID-19 rages in the US, Trump has steadfastly ignored recommendations that people wear masks to help curb the spread of the virus. He himself did not wear one in public until July 11.
Thirty-four states have mask mandates, mostly requiring facial coverings indoors or outdoors around other people, according to AARP, an interest group for the elderly.
Some hotspots, like Florida and Georgia, have no mandate and their Republican governors have resisted pressure to impose one.
Fresh off Wednesday's campaign rollout that featured the Democratic ticket together for the first time showcasing their vision for the nation, Biden, 77, and Harris, 55, held a coronavirus working group with health experts who participated remotely.
"As the (former) vice president has been saying since the beginning of this pandemic, it should be the public health professionals that are leading policy in our country to address this lethal pandemic," Harris said.
The panel included former surgeon general Vivek Murthy, who has been an advisor to Biden throughout the coronavirus crisis.
Biden and Harris then entered a session on the pandemic's impact on businesses and employment in the world's largest economy.
Democrats widely accuse Trump of mishandling the US response to a pandemic that has claimed more than 166,000 lives nationwide.
Critics have blamed him for voicing falsehoods about the virus, including that children are "almost immune" to COVID-19, and ignoring or sidelining some chief scientists and health officials in his administration.
- Top priority -
By highlighting coronavirus recovery at the start of their campaign, Biden and Harris are signaling to voters that the crisis is a top priority -- and a major election issue.
On Monday, the Democratic National Convention begins -- online -- to formally nominate Biden and his running mate.
The party's presidential hopeful introduced Harris at a rollout event Wednesday near his home in Wilmington, at a gymnasium with no public access due to coronavirus concerns.
Harris was announced as Biden's VP pick a day earlier, sparking a grassroots fundraising spree that the campaign said raised an eye-popping $26 million in the first 24 hours, and $34.2 million by the end of Wednesday.
At the rollout, Harris said Trump's "mismanagement" of the pandemic has plunged the nation into its deepest health crisis in a century and the worst economic downturn since the Great Depression.
"There's a reason (the coronavirus) has hit America worse than any other advanced nation. It's because of Trump's failure to take it seriously from the start," she said.
Harris lamented "his refusal to get testing up and running. His flip-flopping on social distancing and wearing masks. His delusional belief that he knows better than the experts."
Trump meanwhile said the economy was experiencing a "V-shaped recovery," despite millions of American families suffering and analysts warning that the country remains in an unemployment crisis.
"As we continue to confront the China virus, we're rebuilding America's economy like nobody thought possible, actually," Trump said Wednesday at the White House.
As for the coronavirus, "it will be going away," Trump told Fox Business Network.
"They scream, 'How can you say that?'" Trump added. "I said, because it's going to be going away."
© 2020 AFP
