Democratic presidential candidate Joe Biden on Tuesday launched a fresh attack on President Donald Trump's "historic mismanagement" of the coronavirus pandemic as the number of confirmed cases rose in many states. 

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Speaking in his hometown of Wilmington, Delaware, the former vice president argued that earlier action by Trump would have reduced the number who fell ill and the economic impact of the virus. 

"The American people don't make enormous sacrifices over the past four months so ... you can waste all their efforts they have undertaken with your midnight rantings and tweets," said Biden, who delivered the speech to reporters in a high school gymnasium.

Biden released an updated plan to tackle the pandemic, which would include more COVID-19 testing and hiring at least 100,000 contract tracers. 

He predicted that the coronavirus outbreak would likely worsen with the onset of the flu season, and said preparations should include more flu vaccines. 

Biden said that, if elected, he would ask the federal government's top disease expert, Dr. Anthony Fauci, to serve another term. 

Trump and his allies say the toll of the virus – which has killed more than 126,000 Americans, according to a Reuters tally – could have been larger without travel bans he put in place for visitors from China, and later from Europe.

87% Unhappy 

Eighty-seven percent of Americans are dissatisfied with the state of the country, and their unhappiness is affecting their political decisions four months before the presidential election, Bloomberg reported, citing a new study from Pew Research Center. 

This unhappiness is affecting perceptions of Trump, who is 10 percentage points behind Biden. Some 54 percent of registered voters back Biden and 44 percent support Trump. The president's approval rating dropped to 39 percent, while 59 percent of Americans disapproved. In the April survey, Trump's approval was 44 percent. 

"Biden is a return to the status quo but it's better than the direction we've been heading," James Pehrson, a Democrat from Fairfax, told USA TODAY. 

"I am not crazy enthusiastic about Biden as a candidate," he said, but Trump is "not fit" for the presidency. 

Still, a slim majority of Americans thinks Trump has a better handle on the economy than Biden. Amid a recession, Trump leads Biden by three points, 51 percent to 48 percent, among voters who said they are very or somewhat confident in the candidate's ability to make good decisions about economic policy, according to Bloomberg. 

(With input from agencies)