The U.S. saw a record number of new coronavirus cases in a single day, with 45,557 diagnoses reported Wednesday, according to a tally by NBC News.
Wednesday's cases top the previous highest daily count from April 26 — during the first peak of the pandemic in the U.S. — by more than 9,000 cases, according to NBC News' tracking data. The World Health Organization reported its single-day record on Sunday, with more than 183,000 new cases worldwide.
Health experts said Monday that the resurgence in cases in Southern and Western states can be traced to Memorial Day, when many officials began loosening lockdowns and reopening businesses.
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The Northeast has reported significant decreases in cases as authorities have maintained policies about social distancing and wearing masks.
Visitors who travel from U.S. hot spots who arrive in New York, New Jersey and Connecticut will be asked to quarantine for two weeks, their governors announced Wednesday.
Unfortunately, as many states struggle to contain the virus after having prematurely loosened restrictions, hospitals are becoming overwhelmed by patients.
In Florida, where more than 109,000 cases have been reported, available capacity for adult intensive care units is only 21 percent, according to state data updated Wednesday. Only 12 percent of Arizona's ICU beds are available, the state health department reported Tuesday.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, praised California's response and likened the battle against the coronavirus to a social justice crusade.
"Californians have risen to the occasion on social issues so well in the past, you've been the leaders in the country on those things," Fauci told the .
"This is an issue that really has social responsibility associated with it," he said.
Even so, California also recorded its biggest single-day tally of new cases Wednesday. An additional 7,149 reported cases brought the state's total of confirmed cases to 190,222.
Gov. Gavin Newsom pleaded with Californians on Wednesday to continue covering their faces.
"You're not invincible from COVID-19," Newsom said. "Quite the contrary. This is a disease that easily spreads, very easily spreads."