EXCESS DEATHS near twice early covid-19 toll.

In the early weeks of the coronavirus epidemic, the United States recorded an estimated 15,400 excess deaths, nearly two times as many as were publicly attributed to covid-19 at the time, according to an analysis of federal data conducted for The Washington Post by a research team led by the Yale School of Public Health.

The excess deaths — the number beyond what would normally be expected for that time of year — occurred during March and through April 4, a time when 8,128 coronavirus deaths were reported. The excess deaths are not necessarily attributable directly to covid-19, the disease caused by the coronavirus. They could include people who died because of the epidemic but not from the disease, such as those who were afraid to seek medical treatment for unrelated illnesses, as well as some number of deaths that are part of the ordinary variation in the death rate. The count is also affected by increases or decreases in other categories of deaths, such as suicides, homicides and motor vehicle accidents.

But in any pandemic, higher-than-normal mortality is a starting point for scientists seeking to understand the full impact of the disease.

The Yale analysis for the first time estimates excess deaths, both nationally and in each state, in those five weeks. Relying on data that the National Center for Health Statistics released Friday, the analysis paints a picture of unusually high mortality that will come into sharper view as more data becomes available.

The analysis calculates excess deaths by using a model to estimate how many people probably would have died absent the pandemic, and then subtracting that number from the overall deaths reported by the NCHS.

The analysis suggests that the deaths announced in the weeks leading up to April 4, based on reports from state public health departments, failed to capture the full impact of the pandemic. Those incomplete numbers were widely cited at a time when many states were making critical decisions about closing businesses and taking other actions to stem the spread of the virus.

The analysis also suggests that the death toll from the pandemic is significantly higher than has been reported, said Daniel Weinberger, a Yale professor of epidemiology and the leader of the research team. More than 55,700 people have died from covid-19, according to a running tally by the Center for Systems Science and Engineering at Johns Hopkins University.

“It’s really important to get the right numbers to inform policymakers so they can understand how the epidemic is evolving and how severe it is in different places,” Weinberger said.

The problem of undercounting coronavirus deaths is not unique to this pandemic or to the United States. In many countries, insufficient testing is a major obstacle to understanding the scale of the pandemic.

In the United States, public health experts say reporting lags, along with the fact that nearly every state initially counted only cases in which the coronavirus was confirmed through a test, contributed to an incomplete picture of deaths in those early weeks.

The NCHS recently started keeping its own tally of covid-19 deaths, separate from the tallies based on states’ reports to the Centers for Disease Control and Prevention.

The NCHS’s tally, based on death certificates, attempts to correct for reporting lags and includes cases that lacked a lab confirmation of the coronavirus. But even the NCHS covid-19 death total from those early weeks — 10,505 as of Sunday — is only twothirds of the excess deaths in the Yale estimate. Information for this article was contributed by Lenny Bernstein, Lenny Bronner, Jacqueline Dupree, Aaron Steckelberg and Reis Thebault of The Washington Post.