Scientific American We have severely undercounted the number of COVID deaths, scientists say. COVID may have killed significantly more people in the U.S. in the first two years of the pandemic than official records indicate, with as many as one overlooked death for every five recorded ones. That brings the total to nearly one million deaths just in 2020 and 2021.
That calculation comes from research published today in Science Advances that seeks to understand how many COVID deaths fell through the cracks of official reporting systems. The untallied cases show the burden of the pandemic in the U.S. fell most heavily on marginalized people. These vulnerable groups are just taking a higher risk at every step, and the accumulation of all of that is this disparity in COVID mortality at the end,” says Mathew Kiang, an epidemiologist at Stanford University and a co-author of the study.
In the new research, Kiang and his colleagues analyzed official records published by the Centers for Disease Control and Prevention for deaths occurring from March 2020 through December 2021 for adults aged 25 and older—some 5.7 million records in all. First, they fed a machine-learning algorithm the records of deaths in hospitals, which at the time were testing most patients for COVID. They trained the algorithm to recognize hospital deaths in which COVID was formally identified as an underlying cause. Then they used the algorithm to flag potential unrecognized COVID deaths by identifying records that looked like hospitalized COVID deaths but occurred in other settings where testing was less likely.