"I think it's a tragedy that the president deals with COVID like it is something not to be worried about when 210,000 people have died. I think it's a travesty," he told reporters as he departed an event in Wilmington, Delaware.
Trump on Wednesday declared that catching the coronavirus was a "blessing from God" that exposed him to experimental treatments he vowed would become free for all Americans, in his first video message since leaving hospital.
Trump, eager to revitalize his ailing re-election campaign, repeatedly stressed how well he felt so far in his recovery from COVID-19, the disease caused by the coronavirus. It was unclear if he was still testing positive for the virus.
"I think this was a blessing from God that I caught it. This was a blessing in disguise," Trump said, adding that his use of the medication from Regeneron Pharmaceuticals Inc had allowed him to experience first-hand how effective it could be.
Asked about Trump's claims, Biden simply replied: "I hope you stay healthy."