US deaths due to coronavirus have topped 16,400, according to a Reuters tally, although there are signs the outbreak might be nearing a peak.

US officials warned Americans to expect alarming numbers of coronavirus deaths this week, even as there was evidence that the number of new infections was flattening in New York state, the epicentre of the US outbreak.

But Americans must resist the temptation to backslide on social distancing now that signs of progress have emerged in the battle against the coronavirus outbreak, US medical and state officials said on Thursday.

US deaths, the second highest in the world, set new daily records on Tuesday and Wednesday with over 1,900 new deaths reported each day, according to a Reuters tally. US deaths were up over 1,600 on Thursday with several states yet to report their latest figures.

US cases topped 459,000 on Thursday, up 27,000 from the prior day.

Only Italy has more deaths with 18,279 fatalities reported, although it has a much smaller population that the United States. After a marked reduction fro

m previous peaks, new infections have picked up in the past two days, frustrating hopes that the illness was in clear retreat.

Another 200 people have been admitted to New York hospitals with COVID-19, fewer than in recent days Credit: EPA

The Italian government is planning to extend its lockdown to contain the country’s COVID-19 outbreak until May 3, two trade union sources told Reuters on Thursday after meeting ministers.

Spain’s prime minister warned on Thursday that nationwide confinement would likely last until May even though he said the worst should soon be over as the death toll slowed from one of the world’s most devastating coronavirus’ outbreaks. Spain reported 15,238 deaths, the third highest in the world.

Italy imposed a nationwide lockdown on March 9 to slow the spread of the virus and Spain followed on March 14. New York state required all residents to stay home except for essential businesses on March 20 and now more than 94 per cent of Americans are under similar orders but the United States has resisted a national stay-at-home order.

Coronavirus hospital admissions in New York have dropped off but the state’s death toll has again spiked.

New York Governor Andrew Cuomo says new cases in hospitals fell to a fresh low of 200 in a sign the disease’s curve was flattening in the state, the epicenter of the US outbreak.

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But at the same time, the state recorded a record-high 799 deaths on Wednesday, for a total of 7067.

“You can’t relax. The flattening of the curve last night happened because of what we did yesterday,” Cuomo said, referring to the shape of graphs tracking new cases.

Several officials have hailed the apparent success of mitigation efforts as reflected in death projections that have been scaled down to 60,000 from more than 100,000.

Still, Anthony Fauci, the nation’s top US infectious disease expert, said it was important that people continue to stay home.

“We’ve got to continue to redouble our efforts at the mitigation of physical separation in order to keep those numbers down and hopefully even get them lower than what you’ve heard recently,” said Fauci, director of the National Institute of Allergy and Infectious Diseases.