The data showed about 215,100 coronavirus deaths and an addition of about 41,700 cases nationwide on Monday. The figure is a decrease from about 44,600 cases a day earlier, which followed four straight days over 50,000.
There were an additional 300 deaths on Monday, according to the data, which also showed a total of 7.8 million cases nationwide since the start of the pandemic.
The data came on the same day researchers at Virginia Commonwealth University said U.S. deaths during the first five months of the health crisis may have been undercounted by as many as 75,000.
Over the past week, new cases nationwide have averaged almost 50,000 -- a substantial increase over the previous week.
"We have got to turn this around," he said.
"We have got to convince Americans that public health measures do not mean shutting the country down," he added. "It's actually an avenue to keeping the country open."
Later Monday, Johnson & Johnson announced it had paused a late-stage human trial for its potential vaccine due to an adverse reaction in one of the volunteers.
Johnson & Johnson executive Joseph Wolk said although it's a setback, the pause in the trial should reassure Americans that the company is following strict scientific and safety standards.
"We're letting safety protocol follow proper procedure here," he said, noting that adverse events in large trials are not uncommon.
In Colorado, Denver Mayor Michael Hancock warned that a surge in cases has brought the city to a "fork in the road," as its seven-day average reached a record high.
The city, he said, could impose new restrictions if the trends don't change quickly.
"That means our capacity in restaurants, retail business, event spaces and personal services, among others, get cut in half," Hancock said. "When so many business right now are struggling just to stay open, that would mean absolute devastation to those businesses."
In Montana, the state's most populous county imposed new restrictions as hospital officials warned healthcare facilities are becoming overwhelmed.
Yellowstone County health officer John Felton said places of worship will be capped at 50% of regular capacity and no more than 25 people will be allowed to gather in any one place, indoors or outdoors. The county has a positivity rate of 62 per 100,000 people, among the highest in the nation.
At 54 positive cases per 100,000, Montana's rate is the third-highest in the United States and trails only North and South Dakota, according to the Brown School of Public Health.
Billings Clinic CEO Scott Ellner has told business leaders the surge is "putting a tremendous strain" on the healthcare system.
"While we remain open and we are making adjustments, our health care workers are tired, they're fatigued," he said.