The United States added 52,000 cases on Monday, the highest one-day total since the middle of August, updated data showed late Tuesday morning. The new figures also listed slightly more than 200,000 dead.
Since the start of the pandemic, there have been 6.89 million cases in the United States.
Dr. Anthony Fauci, the nation's top infectious diseases expert, said a "divisive" culture in the United States has been a hindrance in controlling the COVID-19 pandemic.
Fauci made the remarks Monday night during an interview with Trevor Noah on Comedy Central's The Daily Show.
"I try my best ... in giving a consistent message as often as I can get the message out, something that's just based on the scientific data, based on evidence, which is something that's really very important," he said.
"One of the things that I think gets in the way is that we are in such a divisive state in society that it tends to get politicized. It's almost one side versus the other.
"What has evolved now is that almost people take sides, like wearing a mask is or not is a political statement," said Fauci, director of the National Institute of Allergy and Infectious Diseases. "And that's really very unfortunate.
"Unfortunate because this is a purely public health issue. It should not be one against the other."
Adding to the confusion, he said, are conflicting messages coming from multiple federal sources -- like the Centers for Disease Control and Prevention retracting guidance on Monday and President Donald Trump contradicting CDC Director Robert Redfield last week about the timeline for a vaccine.
"When I'm telling you wear a mask, keep social distancing, avoid crowds, wash your hands, do things outdoors more than indoors, there's nothing political about that. That's a public health message that we know works," he said.
"We have within our capability the ability to turn this around."
In Florida, the country's fourth-largest school district, the Miami-Dade County School Board, voted unanimously Tuesday to allow students the option to return to a full week of in-person school beginning Oct. 21.
It would make the district the largest school system in the United States to return to five days a week of in-school learning. Parents still have the option of keeping their children home for remote learning.
About 51% percent of parents chose to keep their children home at the start of the school year, the Miami Herald reported.
The Florida Department of Health reported nearly 680,000 positive coronavirus cases and more than 13,400 deaths as of Tuesday morning.
In California, the number of residents testing positive fell below 3% for the first time, state health officials said.
The positivity rate for the past week was 2.8%, according to the California Department of Health Care Services -- the lowest figure since the beginning of the pandemic.
The state also reached a grim milestone, as its overall death toll surpassed 15,000 Monday.
In San Diego County, residents and local officials will find out Tuesday if they have fallen a rung into the most restrictive tier in California's COVID-19 ranking system following at outbreak at San Diego State University.
A surge of positive cases last week contributed to overall totals high enough for San Diego to fall into the "purple" tier of the state's reopening system, meaning that restaurants, churches and gyms would have to close their indoor spaces.
County health officials reported about 300 new cases but no deaths Monday.
In Wisconsin, which has one of the nation's fastest-growing outbreaks, nearly 1,300 people tested positive Monday, state officials said -- the seventh straight day with at least 1,000 added cases.
Wisconsin's new caseload has soared by 88% over the last two weeks, the highest rate in the nation. Its positivity rate, nearly 19%, has been driven by cases in the University of Wisconsin system.