When the coronavirus swept through New York City in the spring, it brought with it a staggering surge in deaths — one that was comparable, researchers say, to the 1918 flu pandemic in the city.
That’s according to a study published Thursday in JAMA Network Open that drew on death statistics from public databases to compare the toll during the two outbreaks.
The study looked at two time periods in New York City: 61 days from March 11 through May 11, and the 61 days of October and November 1918, when the influenza outbreak was at its peak.
The study found that during the peak of the 1918 pandemic, 287 per 100,000 New Yorkers died per month, while for this year's pandemic, 202 per 100,000 New Yorkers died per month.
The rate seen during the early months of the COVID-19 pandemic was 70 percent of that seen during the peak of the 1918 flu pandemic, said Dr. Jeremy Faust, an emergency medicine physician at Brigham & Women’s Hospital in Boston and the study's lead author.
“This tells us that these are comparable in terms of their impact,” Faust said. "This virus has 1918 capacity."
In fact, the relative increase in deaths seen during COVID-19 was greater than what was observed during the peak of the 1918 flu, the study found. Compared to the same two-month period in the four years leading up to 1918, there were 2.8 times as many deaths among New Yorkers in October and November 1918. Looking at death rates in the spring in the three years leading up 2020, there were 4.15 times as many deaths in March through May.
That larger relative increase reflects the fact that fewer New Yorkers were dying before COVID-19 than in the years leading up to the 1918 flu, thanks to improvements in public health and modern medicine.
All told, a total of 33,465 New Yorkers out of a population of more than 8 million died during the COVID-19 time period, the study found. During the peak of the 1918 flu, a total of 31,589 New Yorkers died, out of a population of 5.5 million.
Maimuna Majumder, a computational epidemiologist at Harvard Medical School, noted that determining the exact cause for the increased deaths seen in the spring needs further research.
“Some of these deaths are almost assuredly due to the fact that our health care system has been overwhelmed by the pandemic, thus making otherwise treatable conditions less treatable,” she said in an email.
To emergency room physicians who treated COVID-19 patients in New York in the spring, the findings made sense.
“I don't think this was surprising to anyone who worked in an emergency department or in an ICU in March, April or really in May in New York City,” Dr. Craig Spencer, an emergency room physician at Columbia University, said. “The level of death was really just unbelievable."
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Spencer noted that it wasn’t just health care workers at hospitals who saw the toll that the coronavirus exacted on the city. It was paramedics who would arrive at apartments and pronounce patients dead, presumably for cardiac arrest. These patients wouldn’t necessarily be tested for COVID-19, and therefore wouldn’t be included in the official death count. (Indeed, the CDC reported in May that upward of 5,000 deaths in New York City not counted as COVID-19-related deaths may be related to the pandemic.)
He also stressed the difference between the coronavirus and the seasonal flu. “Never once in the 12 years that I've been working in emergency departments has the flu caused my ER to convert to an ICU for weeks at a time,” Spencer said. “Never once have I lost multiple of my colleagues on the front lines to the flu.”
With the virus now relatively under control in New York, Faust said that the rest of the country shouldn’t underestimate the damage the virus is capable of causing.
“I would look back at what happened in New York this year as a cautionary tale,” he said. “It doesn't say that this will happen everywhere. It doesn't say that it won't. It says that it could.”