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.