Confirmed coronavirus cases in the US topped 81,000 on Thursday, more than any other country and overtaking both Italy and China.
Official figures showed the US had 81,378; China has 81,285, and Italy is third with 80,539 cases.
Worlwide, there are now more than 500,000 coronavirus cases.
The US’s grim tally includes at least 1178 deaths and comes after the country’s deadliest day since the beginning of the pandemic, when 223 people died on Wednesday (local time).
The figures come from The New York Times, which has been monitoring confirmed COVID-19 cases across the US. Official reported numbers have skyrocketed since last week, when coronavirus tests were made more easily available for Americans.
The rise comes as New York, New Orleans and other hot spots face a surge in hospitalisations and looming shortages in supplies, staff and sick beds.
New York, with 37,000 confirmed diagnoses and 1290 people fighting for their lives in intensive care, is the epicentre of the American outbreak. There are also fears for other states, including California and Washington.
New York Governor Andrew Cuomo said an expected shortfall of ventilators – machines that support respiration for people who have lost the ability to breathe on their own – was substantial, as a surge of cases overwhelms hospitals.
“Any scenario that is realistic will overwhelm the capacity of the healthcare system,” he said.
“The number of ventilators we need is so astronomical – it’s not like they have them sitting in the warehouse. There is no stockpile available.”
At least one New York hospital has begun a trial of sharing single ventilators between two patients.
Dr. Craig Smith, surgeon in chief at New York-Presbyterian/Columbia University Medical Centre in Manhattan, told staff teams had worked “day and night” to get the split-ventilation experiment going.
Neighbouring New Jersey is another hotspot, with 6876 cases – 2000 new on Friday (Australian time) – and 81 deaths.
Asked about guidelines for allocating ventilators to patients in case of a shortage, Governor Phil Murphy was blunt: “We have to hope for the best, but plan for the worst.”
Elsewhere, Forbes magazine reported on Friday that New Orleans had the world’s fastest rate of growth in new coronavirus cases and might become the pandemic’s next epicentre.
Mardi Gras celebrations last month are believed to have fuelled the local outbreak.
Governor John Bel Edwards said New Orleans hospitals would struggle to manage their patient loads into April. He said Louisiana, which has about 1800 infections, including at least 83 deaths, is rapidly running out of beds and ventilators.
The expanding pandemic comes as President Donald Trump insists the US lockdown should end in time for Easter so the economy can restart.
“We cannot let the cure be worse than the problem itself,” he has tweeted.