America's hospitals will be overrun with coronavirus patients in just eight days and face months of strain, according to Obama's former Medicare boss.

Andy Slavitt, former Acting Administrator of the Centers for Medicare and Medicaid Services, issued the dire warning on Twitter on Saturday along with a string of advice for the public, governments and health workers.

'Last night I was on with state & local officials around the US well into the night.

'By March 23 many of our largest cities & hospitals are on course to be overrun with cases,' he wrote.

Slavitt then listed highlights from the memo he had prepared which included telling people to self-isolate now, closing bars and restaurants, frantically sourcing medical supplies 'even from the black market' if necessary and gearing up for the 'tsunami' of patients that will soon arrive at hospitals.

'The stakes are higher than any most of us have ever experienced: wars, 9/11, whatever,' he later added.

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Medical workers at Kaiser Permanente French Campus test a patient for the novel coronavirus, COVID-19, at a drive-thru testing facility in San Francisco, California on March 12

MEDICARE BOSS'S FULL MEMO Advertisement

As of Saturday morning, there were more than confirmed 2,200 cases of COVID-19 in the US and 50 people had died from it but doctors are warning there are more like 500,000 already infected and that we just do not know it yer because so few people have been tested.

Andy Slavitt, Obama's medicare boss

Dr. Marty Makary, a professor at Johns Hopkins University, said that was likely a gross under-representation of the true scale.

'Don’t believe the numbers when you see, even on our Johns Hopkins website, that 1,600 Americans have the virus. No, that means 1,600 got the test, tested positive.

'There are probably 25 to 50 people who have the virus for every one person who is confirmed.

'I think we have between 50,000 and half a million cases right now walking around in the United States,' he told Yahoo Finance.

Dr. Makary urged people to be more vigilant.

'I’m concerned when I hear a neighbor or a friend say that they’re planning to go to a kid’s swim meet in three weeks or going on vacation next week.

'No — we’re about to experience the worst public health epidemic since polio,' he said starkly.

Nurses at the drive-thru testing station at the University of Washington Medical Center

The estimate of how many more people are going to become infected ranges wildly but congress's doctor has said as many as 150million people may become infected, and Johns Hopkins says as many as 10million may need to be hospitalized because of it.

NEW YORK CONFIRMS FIRST DEATH - AN ELDERLY WOMAN WHO HAD EMPHYSEMA New York confirmed its first coronavirus death on Saturday, an elderly woman who had advanced emphysema when she was admitted to the hospital last week. Mayor Bill de Blasio said in a statement: 'Today, we are confirming our first death due to severe complications from COVID-19. 'The patient, an elderly woman with advanced emphysema, was admitted to the hospital last week as one of our first cases, and had been in critical condition ever since. 'We’ve known from the outset that these people are the most at risk in this pandemic, and today’s news is a sad confirmation of that reality. 'I want to thank the staff of Wyckoff Medical Center for their efforts to save this woman’s life, and all the medical professionals on the front lines protecting our most vulnerable. 'We all have a part to play here. I ask every New Yorker to do their part and take the necessary precautionary measures to protect the people most at risk' Advertisement

The Johns Hopkins Center for Health Security estimates that 38 million Americans will need medical care for COVID-19.

Of that number, as many as 9.6 million will need to be hospitalized and about a third of them - some 3million - will need ICU-level care.

There are only 100,000 ICU beds in America and 790,000 ordinary beds across the country. Not all of those people will need to be hospitalized at the same time, and experts say the crisis could last up to nine months.

But hospitals are not sitting empty, waiting for severe cases of coronavirus patients to arrive. Many are still busy with flu patients, some of whom require intense levels of care.

'This is going to be a fairly tremendous strain on our health system,' Dr. William Jaquis, president of the American College of Emergency Physicians, said.

Dr. Gabriel Cade of Blue Ridge Regional said: 'We've got to expect that this is going to be bad. The situation in Italy is a huge eye-opener.'

A 'moderate' outbreak could result in 200,000 patients needing intensive care, Dr. Leana Wen, an emergency medicine specialist at George Washington said.

'The U.S. only has 100,000 intensive care beds, and most are already occupied. If tens of thousands become sick at once, people will simply not receive the care that they need,' she said.

Aside from people needing intensive care, USA Today predicts that there will be six people fighting for every ordinary hospital bed when the outbreak peaks.

But before anyone is admitted to the hospital, the testing phase needs to be completed.

New York Governor Andrew Cuomo said earlier this week that he was going to look at turning shuttered public venues into make-shift hospitals to treat the sick.

Trump's national emergency declaration on Friday allows hospitals to make fast decisions about hiring, freeing up hospital beds and resourcing supplies.

Trump tweeted on Saturday that he would be attending meetings in the White House all day

It also allows medical personnel to travel and work between states. Many doctors and nurses are coming out of retirement to help in the crisis

From the beginning of the outbreak, there has been consistent criticism of the way the government has handled testing.

As more tests are finally rolled out across the country over the coming weeks and months, there will be a surge in the number of positive cases.

To try to stop the spread, Trump has closed the border with Europe and people in the US are being told to practice social distancing.

On Saturday, he tweeted: 'Attending meetings on Covid-19 in the White House. Working with States and local governments, many of whom have done a great job. Full report latter (sic)'

He later tweeted: 'SOCIAL DISTANCING!'

There have been fears over whether or not the president himself has come into contact with the virus. Several people he has come into contact with over the last few weeks have tested positive for the virus.

At a press conference on Friday where he declared a national state of emergency, he shook hands with several of the people who had joined him to deliver information on a plan.

BILL PASSED TO BEAT CORONAVIRUS

A coronavirus economic aid bill was passed by 363 votes to 40 by the House of Representatives in the early hours of Saturday morning after receiving support from President Trump who declared a national emergency because of the coronavirus on Friday afternoon.

The sweeping relief package includes two weeks of paid sick leave and up to three months of paid family and medical leave as the coronavirus is now confirmed in 49 states. West Virginia is the only state not to have a case by Friday evening.

Trump threw his support behind the legislation which faced a vote in the House early Saturday morning, after announcing a national emergency over coronavirus and later designating this Sunday, March 15, a National Prayer Day.

House Speaker Nancy Pelosi on Friday announced the deal with the Trump administration for an aid package from Congress that would provide free tests even for the uninsured, enhanced unemployment benefits by boosting food stamps, and federal funds for Medicaid.

It will also bolster food programs with additional food aid.

Additionally it will include two weeks of paid sick leave and up to three months of paid family and medical leave for Americans who work for businesses with less than 500 employees or the government and are infected by the virus.

The bill was passed by the House in a post-midnight vote on Saturday morning after a last-minute push to get details agreed. It will now go to a vote in the Senate when it returns next week.

Amid concerns from Republicans on Friday, who claimed they would not vote for the response bill without being sure of Trump's support, the president encouraged both parties to vote yes.

'I fully support H.R. 6201: Families First CoronaVirus Response Act, which will be voted on in the House this evening. This Bill will follow my direction for free CoronaVirus tests, and paid sick leave for our impacted American workers,' Trump tweeted.

'I have directed the Secretary of the Treasury and the Secretary of Labor to issue regulations that will provide flexibility so that in no way will Small Businesses be hurt. I encourage all Republicans and Democrats to come together and VOTE YES!

'I will always put the health and well-being of American families FIRST. Look forward to signing the final Bill, ASAP!' he added.