The death toll in the United States by July 2020 is 8% to 12% higher than it would have been if the coronavirus pandemic had never occurred. That’s at least 164,937 deaths above the expected number for the first seven months of the year – 16,183 more than the number attributed to COVID-19 so far for that period – and could be as high as 204,691.
When someone dies, the death certificate records an immediate cause of death, along with up to three basic conditions that “initiated the events that caused the death.” The certificate is submitted to the local health department, and details are reported to the National Center for Health Statistics.
As part of the National Vital Statistics System, the NCHS then uses this information in a variety of ways, such as tabulating the leading causes of death in the United States ̵1; currently heart disease, followed by cancer. Sometime this fall, COVID-19 is likely to become the third leading cause of death for 2020.
Design from the past
To calculate the excess deaths requires a comparison with what would have happened if COVID-19 had not existed. Of course, it is not possible to observe what did not happen, but it is possible to estimate using historical data. The Centers for Disease Control and Prevention does this using a statistical model, based on data from the previous three years of mortality, including seasonal trends, as well as adjustments for data reporting delays.
So looking at what happened over the last three years, the CDC projects what it could have been. Using a statistical model, they are also able to calculate the uncertainty in their estimates. This allows statisticians like me to assess whether the observed data look unusual compared to the forecasts.
The number of redundant deaths is the difference between model predictions and actual observations. The Centers for Disease Control and Prevention also calculates an upper limit on the estimated number of deaths – which helps determine when the death toll is extremely high compared to historical trends.
Visible clearly visible in a graph of these data is the increase in deaths that begins in mid-March 2020 and continues to the present day. You can also see another period of excessive deaths from December 2017 to January 2018, attributed to an extremely virulent flu strain that year. The excessive death rate in 2020 makes it clear that COVID-19 is much worse than the flu, even when compared to a bad flu year like 2017-18, when about 61,000 people in the US died from the disease.
The large increase in deaths in April 2020 corresponds to the coronavirus outbreak in New York and the Northeast, after which the number of excess deaths decreased regularly and significantly until July, when it began to rise again. This current attack on excessive deaths is attributed to the blasts in the South and West that have occurred since June.
The records tell the story
A sophisticated statistical model is not needed to see that the coronavirus pandemic is causing substantially more deaths than would otherwise have occurred.
The number of deaths officially attributed to COVID-19 in the United States exceeded 148,754 by August 1. Some people who are skeptical about aspects of the coronavirus suggest that these are deaths that would have happened anyway, probably because COVID-19 is particularly deadly to the elderly. Others believe that because the pandemic has drastically changed lives, the increase in COVID-19-related deaths is probably offset by reductions from other causes. But none of these possibilities are true.
In fact, the number of excessive deaths currently exceeds the number attributed to COVID-19 by more than 16,000 people in the US What’s behind this discrepancy is still unclear. COVID-19 deaths can be calculated, or a pandemic can cause an increase in other types of death. Probably maybe some of both.
Whatever the reason, the COVID-19 pandemic has resulted in more deaths than would otherwise have occurred … and it is not over yet.
Ronald D. Fricker Jr. is Professor of Statistics and Associate Dean for Faculty and Administration Affairs at Virginia Tech in Blacksburg, Va. This was first published by The Conversation – “Up to 204,691 additional deaths in US so far this pandemic year”