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's about 5,300 more deaths that had been previously attributed to the coronavirus during that time period.
These so-called "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 says, adding the 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 the coronavirus are believed to be widely undercounted worldwide, due in large part to limits in testing and the different ways countries count the dead.
Through 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 are sure enough to list the virus on the death certificate.
In its analysis, the report released Monday said the 5,293 excess deaths were on top of both 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 recognized as being directly attributable to COVID-19," the report found.
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