DENVER, the United States - "I think that there's a lot of concern that we could start to see a real upsurge and this is a continuation of a broader trend underway as we head into the colder months," Dr. Scott Gottlieb said Sunday.

Gottlieb, former head of the US Food and Drug Administration, appeared on Face the Nation of CBS to caution that the country is "taking a lot of infection into a very dangerous season" for the virus.

Gottlieb isn't the only expert that has given a warning in the past few days. As a new wave of novel coronavirus cases slowly seeped into America, experts from coast to coast sounded the alarm.

"Where there are already cracks in the system, those cracks become earthquakes," Dr. Chris Pernell, University Hospital's chief strategic integration and health equity officer, told NBC News Saturday.

"A second surge of COVID-19 this fall and winter could be catastrophic for the US, and it's not just more sick people that doctors worry about," NBC's report noted.

Experts agree that the economic strain of continued COVID-19 services -- especially in the wake of an anticipated upsurge -- could be devastating for many hospitals.

By the end of 2020, hospitals across the United States will lose about 300 billion US dollars, according to the American Hospital Association, noting that during the pandemic, hospitals have absorbed the costs of extra supplies, including masks and gloves, and without federal support, many face bankruptcies.

Many experts agree that the upsurge has begun or is on its way, although Gottlieb said it was "unclear" if the recent upsurge "is the start of a persistent trend heading into the fall and the winter," or whether it was a "temporary" upswing resulting from Labor Day festivities.

As of Monday, in total, the United States has 7,127,210 infections with 204,861 deaths as a result of the pandemic, "more than double Europe's case count, and many more people live there," CNN said.

Across the country, daily cases were largely on a downward trend through August and early September from highs in July, but are going up again now, National Public Radio (NPR) noted Saturday.

Anthony Fauci told the media several days ago, "The US is still in its first COVID-19 wave and should be prepared for the 'challenge' of fall and winter."

But Fauci, who has served as the director of the National Institute of Allergy and Infectious Diseases since 1984, may revise his assessment, based on hard data in just the past week.

The country reported more than 58,461 new COVID-19 cases on Friday, according to the Johns Hopkins University Coronavirus Tracker.

Overall, about two-dozen states and territories reported an upward trend in new infections, with some states setting and breaking records in days, according to NPR.

The US Centers for Disease Control and Prevention has projected there would be up to 226,000 coronavirus deaths in the United States by Oct 17.

On the East Coast, New York Governor Andrew Cuomo announced Saturday there were 1,005 positive cases tallied on the previous day, Friday, out of 99,953 tests, for a 1 percent positive rate.

"Is there cause for concern? As long as COVID is here, yes," Cuomo's aide Gareth Rhodes posted on Twitter.

Rhodes stressed Saturday that the new positive-case number came out of nearly 100,000 tests, compared to about 60,000 tests daily in June.

From late July through the start of September, the Empire State was seeing an average of around 660 people test positive per day.

Last week, New York averaged 817 positive tests per day, Cuomo's office said.

In the Midwest, four states reported record one-day increases in COVID-19 cases on Saturday, a national trend for a second straight week, according to a Reuters analysis.

In Wisconsin, the state's Department of Health said it had identified 2,817 new infections on Saturday, its highest daily total since the pandemic began. It broke the record of 2,533 new infections from Sept 18.

"Wisconsin is now experiencing unprecedented, near-exponential growth of the number of COVID-19 cases in our state," Governor Tony Evers said.

Wisconsin's hospitalizations have set new records for six days in a row, according to state health data, rising to 543 on Friday from 342 a week ago.

South Dakota's hospitalizations set records five times last week, rising to 213 on Saturday, the Reuters analysis noted, adding that all Midwest states except Ohio reported more cases in the past four weeks as compared with the prior four weeks.

In California, the state's top health official, Health and Human Services Secretary Mark Ghaly, warned Friday night that the latest data of COVID-19 in the state was worrisome, since it could be an early sign showing a "second wave" of the virus is coming.

The Golden State saw 3,400 new cases on Friday in the previous 24 hours, marking a slight uptick from recent lows. Meanwhile, the state's positivity rate, state-wide coronavirus-related emergency department visits and new hospitalizations due to the virus are all on the rise in the past week.