New York City's death toll from coronavirus may be thousands worse than the official tally kept by the city and state, according to analysis by the US Centres for Disease Control and Prevention.
Between mid-March and early May about 24,000 more people died in the city than researchers would ordinarily expect based on the season, the report said.
That is about 5,300 more deaths than had been previously attributed to the virus during that time period.
These "excess deaths" could have been caused by byproducts of pandemic, the report found, including "the demand on hospitals and health care providers and public fear related to Covid-19" prompting delays in people seeking or receiving lifesaving care.
"Tracking excess mortality is important to understanding the contribution to the death rate from both Covid-19 disease and the lack of availability of care for non-Covid conditions," the report said, adding that further investigation is required.
The report, based on data compiled by the New York City Department of Health and Mental Hygiene, underscored the challenges authorities face in assessing - and quantifying - the human toll of the crisis.
Even deaths caused by coronavirus are believed to be widely undercounted worldwide, due in large part to limits in testing and the different ways countries count the dead.
By Sunday New York City had recorded nearly 14,800 deaths confirmed by a lab test and another nearly 5,200 probable deaths where no test was available but doctors were sure enough to list the virus on the death certificate.
In its analysis the report released yesterday said the 5,293 excess deaths were on top of confirmed and probable fatalities.
Deaths of people with chronic health problems like heart disease and diabetes - conditions closely associated with coronavirus mortality - "might not be recognised as being directly attributable to Covid-19," the report found.
The report was issued as several regions of upstate New York that have shown progress in taming the outbreak were preparing to gradually restart economic activity by the end of the week.
New York Governor Andrew Cuomo shut down the entire state on March 22 as the New York City area emerged as a global pandemic hotspot, but the outbreak has been less severe in the state's smaller cities and rural areas.
He said three upstate regions have met all criteria for opening some business activity after May 15 - the Southern Tier, Mohawk Valley and the Finger Lakes. Other upstate regions were making progress and could follow soon after.
The reopening regions still need to work out logistics, such as creating regional "control rooms" to monitor the effects of the reopening.
"This is the next big step in this historic journey," the Democratic governor said at his daily briefing.
New York is also poised to launch a training plan for the huge corps of disease detectives it plans to deploy to track people who might have been exposed to coronavirus.
The effort, seen as a key to keeping the outbreak from flaring again once it is under control, is likely to involve hiring several thousand people who have no background in public health.