A persistent falsehood has been circulating on social media: the number of COVID deaths is much lower than the official statistic of more than 218,000, and therefore the danger of the disease has been overblown. In August President Trump retweeted a post claiming that only 6 percent of these reported deaths were actually from COVID-19. (The tweet originated from a follower of the debunked conspiracy fantasy QAnon.) Twitter removed the post for containing false information, but fabrications such as these continue to spread. U.S. Representative Roger Marshall of Kansas complained in September that Facebook had removed a post in which he claimed that 94 percent of COVID-19 deaths reported by the Centers for Disease Control and Prevention “were the result of 2-3 additional serious illnesses and were of advanced age.”
Now some facts: Researchers know beyond a doubt that the number of COVID-19 deaths in the U.S. have surpassed 200,000. These numbers are supported by three lines of evidence, including death certificates. The inaccurate idea that only 6 percent of the deaths were really caused by the coronavirus is “a gross misinterpretation” of how death certificates work, says Robert Anderson, lead mortality statistician at the CDC’s National Center for Health Statistics.
The scope of the coronavirus’s deadly toll is clear, even if final numbers will not be known until the pandemic is over. “We’re pretty confident about the scale and order of magnitude of deaths, but we’re not clear on the exact number yet,” says Justin Lessler, an infectious disease epidemiologist at the Johns Hopkins Bloomberg School of Public Health. To understand why the figures contain some uncertainty, it is important to know how they are collected and calculated.
The first source of death data is called case surveillance. Health care providers are required to report cases and deaths from certain diseases, including measles, mumps and now COVID-19, to their state’s health department, which, in turn, passes this information along to the CDC, Anderson says. The surveillance data are a kind of “quick and dirty” accounting, says Shawna Webster, executive director of the National Association for Public Health Statistics and Information Systems. The states gather all the information they can on these diseases, but this is the first pass of the accounting—no one has time to double-check the information or look for missing lab tests, she says. For that, you have to look for the next source of information: vital records.
This second line of evidence comes from the National Vital Statistics System, which records birth and death certificates. Every time somebody dies, a death certificate is filed in the state where the death occurred. And after the records are registered at a state level, they are sent to the National Center for Health Statistics, which tracks deaths at a national level. Death certificates are not filed in the system until outstanding test results are in and the information is as complete as