New York has reported its highest number of coronavirus-related deaths in a single day, with even veteran doctors and nurses expressing shock at the speed with which patients were declining and dying.
The number of coronavirus cases in New York state alone approached 150,000 on Wednesday, the highest in the US, even as authorities warned the state's official death tally may understate the true number.
"Every number is a face, " said New York Governor Andrew Cuomo, who ordered flags flown at half-staff across New York in recognition of the toll.
"This virus attacked the vulnerable and attacked the weak and it's our job as a society to protect the vulnerable."
Doctors and nurses say it isn't just elderly or patients with underlying health conditions who appear to be fine one minute and at death's door the next. It can happen for the young and healthy, too.
Patients "look fine, feel fine, then you turn around and they're unresponsive," said Diana Torres, a nurse at Mount Sinai Hospital in New York City, the epicentre of the pandemic in the United States where the virus has infected nearly 430,000 people.
"I'm paranoid, scared to walk out of their room."
New York officials said a recent surge in the number of people dying at home suggests the most populous US city may be undercounting how many have died of COVID-19, the respiratory illness caused by the pathogen.
"I think that's a very real possibility," Cuomo told his daily news briefing.
Cuomo said 779 people died in the past day in his state. New Jersey Governor Phil Murphy said 275 had died there. Both totals exceeded one-day records reported just a day earlier.
Cuomo said the death count would continue at the current level or increase in the coming days as critically ill patients, who have been hospitalised for more than a week and on ventilator machines to assist in breathing, die.
US deaths due to coronavirus topped 14,700 on Wednesday, the second-highest reported number in the world behind Italy, according to a Reuters tally. New York has accounted for nearly half of them.
Officials have warned Americans to expect alarming numbers of coronavirus deaths this week, even as an influential university model on Wednesday scaled back its projected death toll by 26 per cent to 60,000.
California, like New York, had one of its highest single-day death tolls with 68 people dying of COVID-19 in the past 24 hours, Governor Gavin Newsom said.
Louisiana Governor John Edwards said the number of new coronavirus cases reported in the past 24 hours - 746 - was lower than recent days. Louisiana had been one of the nation's hot spots for the virus.
"We do believe we are beginning to see the flattening of the curve," he said.
Meanwhile, President Donald Trump said he would like to reopen the US economy with a "big bang", but that the death toll from the coronavirus needs to be on the down slope before that can happen.
Australian Associated Press