Americans prepare for what the country's top doctor warned Sunday would be "the hardest and saddest week" of their lives.

According to Surgeon General Jerome Adams on Fox News, fatalities from the novel coronavirus would make this advent reminiscent of Pearl Harbor and 9/11.

However, New York City witnessed a slight decrease in daily deaths, ICU admissions, and patients who needed breathing tubes inserted, according to Gov. Andrew Cuomo. It is the U.S. epicenter of the pandemic.

The governor warned that it was too soon to tell the significance of those numbers.

Meanwhile, the U.K. was beheld deadliest COVID-19 hot spot in Europe after recording a 24-hour jump in deaths that surpassed previously the most hard-hit Italy.

The tally of deaths is exploding in New York, Louisiana, and Michigan with some governors declaring a national order to stay indoors.

New York reported Sunday that there were almost 600 new deaths for a total of 4,159 fatalities and 122,000 total cases, making it the hardest-hit state.

Bodies of victims of the coronavirus were piled in bright orange bags inside a makeshift morgue outside Brooklyn's Wyckoff Heights Medical Center.

According to Adams, there "is a light at the end of the tunnel if everyone does their part for the next 30 days."

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"There is hope, but we've also got to all do our part."

Medical equipment and supplies were urgently needed across the Philadelphia region on Palm Sunday.

New Jersey Gov. Phil Murphy declared that the state acquired an additional 500 ventilators from the national emergency reserve, but still short of at least 1,350 more.

Authorities are alerting that the next two weeks will be critical in tackling the spread of the coronavirus. According to data collated by Johns Hopkins University, the nationwide total of fatalities had risen to at least 8,503 people, with nearly 312,245 infected.

U.K.'s prime minister, Boris Johnson, was admitted to the hospital 10 days after testing positive for the coronavirus in what his office deemed as a "precautionary step." Queen Elizabeth II called out Britons to practice self-discipline in "an increasingly challenging time."

Along with the number of people dying seemingly slowing down in New York City, the same goes for Spain and Italy.

Britain registered 708 new coronavirus fatalities Saturday while Italy reported 631 deaths on the same day.

Adams announced, "This is going to be our Pearl Harbor moment, our 9/11 moment, only it's not going to be localized. It's going to be happening all over the country. And I want America to understand that."

Host Chris Wallace pressed the surgeon general on President Donald Trump's recurring promotion of the antimalarial drug hydroxychloroquine as a cure for the coronavirus. The drug has not been approved yet as a treatment while experts have cautioned a run on supplies could result in a shortage for those in need of it for its FDA-approved uses.

On Saturday's coronavirus task force briefing at the White House, Trump said that this week and the next could be the most difficult in the battle against the coronavirus, citing that "there will be a lot of death."

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