The Myth of Exaggerated Mortality Statistics
The tragic truth is that COVID-19 is a potentially fatal disease. Some have questioned, however, the official number of deaths attributed to the coronavirus pandemic in the U.S., which stood at the beginning of November at over 230,000. People have asked us how these rates are arrived at and what’s actually in a death certificate. Is there any truth to the rumor that the number of deaths from COVID-19 has been grossly exaggerated?
There are several numbers to keep in mind here. First is the absolute number of deaths attributed to COVID-19, which as mentioned above stood at 230,000 on November 1, but was poised to go up as increasing numbers of cases of people testing positive for the virus were being reported. That number depends on accurate reporting of deaths, which we will discuss in a moment.
The second statistic is the rate of deaths per people actually infected by the virus. Again as of November 1 there were approximately 9.3 million people reported to have been infected with the virus that causes COVID-19 (SARS-CoV-2) in the U.S. since the pandemic began. With the above number of reported deaths, that would yield a U.S. mortality rate of 2.5% (also known as the case fatality rate). In other words, and consistent with the reported rate given by the Johns Hopkins University Coronavirus Resource Center, a bit more than 2 out of every 100 people who contract the virus would die.
Case Fatality Rate Likely an Overestimate
But that case fatality rate is probably an overestimate because the denominator—the total number of people who have been infected with SARS-CoV-2—is likely an undercounting of the true number of infected people. This is because many asymptomatic people who are actually infected with the coronavirus are never tested and therefore not included in that 9.3 million number of cases. In fact, some estimates suggested that there may be as many as ten times the number of positive cases of SARS-CoV-2 infection in the U.S. than we know about, which would make the case fatality rate as low as 0.25% or 2 to 3 people dying per 1000 people infected. Of course, the case fatality rate is higher in more vulnerable people, including those with certain underlying health conditions, the elderly, and people of color. And even if the whole population mortality rate were at the low 0.25% number, it is of course unacceptable to let 2 to 3 people per 1000 die from a viral illness.
An Outrageous Claim
What if, as some have claimed, the numerator for the COVID-19 case fatality rate is an overestimate? That would mean the death rate is potentially even lower than somewhere between 0.25% and 2.5%. It turns out that this claim is untrue and represents a misunderstanding about what is written on death certificates in the U.S.
When someone dies, a death certificate is filed within the state in which the death occurs and once registered is then sent to the U.S. National Center for Health Statistics. Death certificates have a standard format that includes a page to list “causes of death.” There are two parts to this. In Part one, the responsible clinician filling out the form reports the sequence of events leading to death. This sequence ends on the top line of the death certificate, line a, which gives the most immediate reason the person died. Lines below that give the conditions that led to the death, with the actual underlying cause of death (UCOD) falling to the last line in Part one.
That means if someone picks up a death certificate and looks at line a in Part one, they may not see the actual disease that was responsible for the person dying. Let’s first take the example of someone who died of a heart attack. The most immediate cause of death–the event that occurred right before the person died–might have been a rupture of the wall of the heart, called the myocardium. This was in turn caused by the death from lack of oxygen of some of the muscle tissue that forms the myocardium, which in turn was caused by a blood clot in one of the coronary arteries that line the outside of the heart that bring oxygen to the myocardium. All of this was caused by the UCOD, chronic heart disease (in this case coronary artery disease). So Part one would look like this:
a. Rupture of myocardium
b. Acute myocardial infarction
c. Coronary artery thrombosis
d. Atherosclerotic coronary artery disease
Notice that the reason this person died was because of hardening of the coronary arteries over many years, but you would not know that if you just glanced at line a.
Then there is also Part two, which lists other conditions the individual may have had which contributed but were not part of the chain that led to. These might include kidney failure, for example, or diabetes.
You can see that it is almost never correct to put only one thing down as the cause of death on a death certificate. This led some conspiracy theorists to make the incorrect claim that only 6% of cases of death said to be caused by COVID-19 were actually caused by COVID-19. What they missed is that in the bulk of cases in which someone dies from COVID-19 it is listed on line c or d of Part one as the underlying causes of death (UCOD). The 6% of death certificates that listed only COVID-19 are probably just incomplete. For example, Part one of someone who died from COVID-19 might look like this:
a. Acute respiratory distress
Clearly, COVID-19 is the cause of death here because it is the reason the person got pneumonia and then couldn’t breathe and then died. There might also be contributing conditions in Part two, like diabetes and high blood pressure (hypertension).
Writing in Scientific American, Christie Aschwanden stated emphatically that “Researchers know beyond a doubt that the number of COVID-19 deaths in the U.S. have surpassed 200,000.” Aschwanden goes on to explain that there are multiple ways scientists know this in addition to the official death certificates. One of these is the excess deaths method. Here, scientists look to see if there are a significant number of deaths in any period above what has historically been the case. “In a paper published in JAMA this month,” Aschwanden writes, researchers “examined death records in the U.S. from March 1 through August 1 and compared them with the expected mortality numbers. They found that there was a 20 percent increase in deaths during this time period—for a total of 225,530 excess deaths—compared with previous years.” Since only two-thirds of those deaths were attributed to coronavirus on the death certificates, we can safely conclude that the number of deaths reported from COVID-19 is likely an underestimate.
Charges that doctors deliberately inflate COVID fatalities by falsely listing it as the cause of death on death certificates have been soundly condemned by many medical associations. In fact, if anything there are probably more deaths from COVID-19 than we know about.
As healthcare professionals become more and more adept at treating patients sickened with COVID-19 it may be that the mortality rate will fall. Still, some of those people will have suffered through stays in the ICU and some will continue to have symptoms for months after they leave the hospital. The data here are all too clear: SARS-CoV-2is a deadly virus that has killed more than 200,000 Americans and more than one million people worldwide. It is a scourge that thankfully most of us are taking seriously.