New Yorkers’ Risk of Covid Death Was Double Earlier Estimates

(Bloomberg) -- New Yorkers’ risk of death from the coronavirus during the spring, the peak of the hard-hit city’s outbreak, was about double that of earlier estimates from other regions, according to a new analysis that highlights the pandemic’s lethal impact.

Despite efforts to slow the contagion, 21,447 New Yorkers died from Covid-19 from March through early June, researchers from Columbia University and the city’s health department reported Monday in the medical journal Lancet Infectious Diseases. The risk of dying from a SARS-CoV-2 infection was 1.39% if both confirmed and probable Covid-related deaths were included; that compared with about 0.7% of infections reported earlier in China and France, the authors said.

“Our results are based on more complete ascertainment of Covid-19-associated deaths in New York City than are those from previous studies, and thus probably reflect the true, higher burden of death due to Covid-19 than previously reported elsewhere,” researchers led by Wan Yang, an assistant professor of epidemiology at Columbia’s Mailman School of Public Health, said in the study.

New scrutiny of the pandemic continues to reveal its outsized impact on society. While 216,025 deaths from Covid-19 have been reported in the U.S. as of Oct. 15, that tally may underestimate the total impact of the pandemic, the Centers for Disease Control and Prevention in Atlanta said Tuesday in a separate report. Overall U.S. deaths from late January through Oct. 3 were almost 300,000 higher than expected, based on long-term mortality trends, according to the CDC study.

Risk Still Unclear

Still, the infection-fatality risk from Covid-19 in the U.S., which has reported the most cases in the world, “remains unclear,” according to the Lancet Infectious Diseases study.

The infection-fatality measure estimates the proportion of deaths among all infected individuals. Calculating the risk for SARS-CoV-2 is challenging because of the large number of undocumented infections, fluctuating rates of disease detection and inconsistent reporting of deaths, the researchers said.

So far, most fatality ratios during the pandemic have been based on cases detected through surveillance and estimated using crude methods, giving rise to widely variable case-fatality ratio estimates by country -- from less than 0.1% to over 25%, according to the World Health Organization. In New York City, the crude confirmed case-fatality ratio or risk was estimated to be 8.23% from March 1 to June 6.

Read More: Understanding the Virus and Its Unanswered Questions

Worldwide, more than 40 million Covid-19 cases and 1.1 million deaths have been reported. The high fatality risk means “governments must account for and closely monitor the infection rate and population health outcomes and enact prompt public health responses accordingly as the Covid-19 pandemic unfolds,” the Columbia and New York City researchers said.

The study, which received funding from the National Institute of Allergy and Infectious Diseases and New York City Department of Health and Mental Hygiene, used available case, mortality, and mobility data to estimate the infection-fatality risk across five age from March 1 to June 6, before the city began a phased reopening.

After reporting an initial case on March 1 in a traveler, New York City quickly became the epicenter of the pandemic in the U.S. The city’s public schools were closed March 16, and a city-wide stay-at-home order was imposed six days later on all non-essential workers.

Young Adults

There was substantial under-detection of infections, which varied by age group and over time, in part due to changing testing criteria, the researchers found. Only about 2% of infections were detected in the first week of March, increasing to 17% by mid-March. Shortages in testing and personal protective equipment meant testing was restricted to severely ill patients in early April, before it became more widely available in May.

By July, many places where restrictions were lifted saw increases in the number of Covid-19 cases among young adults. These continuous infections could ignite new epidemics and lead to further devastating effects, the researchers said.

“As such, young adults must strictly adhere to physical distancing and preventive measures,” such as mask-wearing in places with continuous transmission, they said, “despite their relatively low infection-fatality risk.”

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