Are COVID Death Numbers Comparing Apples and Oranges?

This article argues that the US Centers for Disease Control (CDC)’s April 2020 guidance for filling out death certificates for possible COVID-19 related deaths strongly encourages, if not requires, assigning COVID-19 as the underlying cause of death (UCOD) in any death where COVID-19 or the SARS-COV-2 virus may be present, which appears to differ from common historical practice for pneumonia and influenza deaths where pneumonia was frequently treated as a “complication,” a cause of death but not the underlying cause of death.

This means the number of COVID deaths should be compared to a count of death certificates where pneumonia and influenza were listed as a cause of death or even a lesser contributing factor, a historical number which appears to have been at least 188,000 per year based on the CDC FluView web site. The proper comparison number may be even larger if deaths that historically were listed as heart attacks, cancer or other causes than pneumonia or influenza are also being reassigned due to the April 2020 guidance.

The CDC has at least three different historical pneumonia and influenza death numbers. These are the leading causes of death report numbers of about 55,000 deaths per year which appears based on death certificates, a poorly documented mathematical/computer model which attributes about 55,000 deaths per year with a large error to the influenza virus, and the FluView web site which attributed about 188,000 deaths per year to pneumonia and influenza.

The leading causes of death historical numbers appear based on the underlying cause of death listed on the death certificate whereas the FluView historical numbers appear based on death certificates that list pneumonia or influenza as a cause of death, in most cases not the underlying cause of death. The historical FluView death numbers appear to be the proper baseline for comparison to COVID-19, although an even larger number is possible if there has been practically significant reassignment of heart attacks and other deaths as well.

This would mean that COVID-19 is less deadly than popular perceptions based frequently on comparisons to “flu death numbers” of about 55,000 per year apparently derived either from the CDC’s leading causes of death report or the influenza virus model.

Note that this is not a claim that COVID-19 or SARS-COV-2 plays no causal role in the deaths: a death “with” COVID rather than a death “due to” COVID in popular debates. Rather, the proper interpretation is probably that COVID-19 acts predominantly as an opportunistic infection instead of an inherently deadly infection able to easily kill healthy young people with a strong immune system. Vaccines are likely to have small or no ability to prevent death from an opportunistic infection since the infected vaccinated person will have a weak or failed immune system with little or no ability to produce the immune response learned from the vaccination.

The language and numbers on the CDC web sites and official reports and documents are remarkably confusing and grossly contradictory in some cases — such as the historical number of deaths attributed to pneumonia and influenza which differs by over a factor of THREE. Error bars or confidence levels on most numbers such as the death numbers are not reported as required by common scientific and engineering practice. These practices have been harshly criticized for years by scientists and medical experts such as Peter Doshi. Consequently it is impossible to make definite statements about the meaning of the numbers and the definitions of measured quantities discussed below.

This is a complex life-and-death subject with many nuances. Each section below expands each key point in detail, discussing the nuances and unknowns. Some facts and arguments are repeated in different sections for clarity.

Three Different Historical Pneumonia and Influenza Death Numbers

The United States Centers for Disease Control (CDC) documents and web site present at least THREE different historical (pre-2020) estimates of deaths from “influenza and pneumonia,” “pneumonia and influenza,” and/or “influenza” or the “flu” presumably meaning the influenza category of viruses.  Which of these three death numbers, one of which differs by a factor of OVER THREE from the other two, should be compared to COVID-19 deaths?  Indeed, it could well be incorrect to compare any of them to the COVID-19 deaths.

These three pneumonia and influenza death numbers are the value in the annual leading causes of death report — about 55,000 deaths each year,  the tables of “pneumonia and influenza” (abbreviated as P&I) from the National Center for Health Statistics (NCSH) used on the FluView web site — about 188,000 deaths per year, OVER THREE TIMES the leading causes of death number, and the output of a poorly documented model of deaths attributed to the influenza category of viruses, a broad range centered at about 55,000 deaths per year.

Deaths attributed to COVID-19 in 2020 have frequently been compared to an estimate of about 55,000, either to the date of the report or for the entire year.  The language used is often unclear but appears to refer to either the CDC’s influenza mathematical model or the leading causes of death number, which are similar numbers but technically not the same.

This article argues that the current COVID-19 death numbers are best compared to the larger FluView numbers, although an even larger different number may be appropriate if deaths that would have been attributed to heart attacks, strokes, or other blood coagulation related disorders in the absence of a positive SARS-COV-2 test or diagnosis are included in the current COVID-19 death counts.

The CDC FluView Web Site

The CDC FluView web site shows that six to ten percent of deaths, varying seasonally, are due to pneumonia and influenza (P&I) according to the vertical axis label on the FluView Pneumonia & Influenza Mortality plot.  The underlying data files from the National Center for Health Statistics (NCHS) list about 188,000 deaths per year attributed to pneumonia and influenza.

NOTE: https://www.cdc.gov/flu/weekly/fluviewinteractive.htm and click on P&I Mortality Tab

Note also that deaths attributed to “pneumonia and influenza” on the FluView web site are highly seasonal. A substantial increase over the summer is expected during the winter (or rainy season in Northern California and similar regions), peaking in December and January each year.

Also note that the seasonal variation is sinusoidal — like the oscillation of a pendulum or a mechanical spring. Contrary to popular culture, there is no clear step up when schools open in the fall or step down when schools close for the summer. It looks very much like something driven by the Sun, directly or indirectly by some mechanism or mechanisms. Possible mechanisms include Vitamin D production from sunlight, destruction of viruses and bacteria in the air or on surfaces by ultraviolet light in sunlight, general health benefits of a warm environment, or some other Sun-driven phenomenon.

The Leading Causes of Death Report

In contrast, the CDC’s leading causes of death report Table C, Deaths and percentage of total deaths for the 10 leading causes of death: United States, 2016 and 2017 on Page Nine (see screenshot below) attributes only two percent of annual deaths (about 55,000 in 2017) to “influenza and pneumonia.”

The difference between the CDC FluView and leading causes of death report numbers is probably due to the requirement that pneumonia or influenza be listed as “the underlying cause of death” in the leading causes of death report and only “a cause of death” in the FluView data. This is not clear. Many deaths have multiple “causes of death.” The assignment of an “underlying cause of death” may be quite arbitrary in some cases. Despite this, none of these official numbers either in the leading causes of death report or the FluView web site are reported with error bars or error estimates as required by common scientific and engineering practice when numbers are uncertain.

A longer, more detailed discussion of the FluView, leading causes of death, and the CDC’s influenza virus death model death numbers (yet another number) may be found below. It appears likely the FluView death numbers are defined similarly to current COVID-19 death counts; the reasons for this are explained in some detail.

Which Pneumonia and Influenza Death Numbers Should Be Compared to the COVID-19 Death Numbers?

The FluView and Leading Causes of Death numbers for “pneumonia and influenza” differ by a factor of OVER THREE. Note that both the FluView and Leading Causes of Death numbers have no error bars or error estimates given, implying exact numbers in common scientific and engineering practice.  Should the number of COVID-19 deaths be compared to the FluView number or the leading causes of death number or some other number?

The CDC Influenza Deaths Model

The CDC also uses a poorly documented mathematical model that attributes roughly 55,000 deaths from pneumonia and influenza to the influenza virus as the underlying cause, a number roughly comparable to the total pneumonia and influenza deaths in the leading causes of death. The influenza virus is confirmed by laboratory tests in only a small fraction of pneumonia and influenza deaths, about 6,000 per year.

Although the language is often unclear in the CDC documents and web site, the CDC appears to claim that an initial influenza infection which disappears or becomes undetectable in laboratory tests leads to the subsequent pneumonia, presumably a bacterial pneumonia although other viruses would be consistent with some lab tests. Based on this argument, the CDC appears to attribute most pneumonia deaths where historically pneumonia was listed as the “underlying cause of death” to the influenza virus for which there is a flu vaccine that the CDC promotes heavily — even though laboratory tests frequently fail to confirm influenza or even detect other viruses or bacteria instead. The “underlying cause of death” is discussed in more detail below.

As shown in the graphic above, the CDC web site Disease Burden of Influenza (Figure 1) appears to give a range from 12,000 to 61,000 influenza deaths from this model. The graphic does not indicate if this range is a 95 percent confidence interval — a common scientific and engineering practice — or some other error estimate. The range in the graphic does not appear to match any of the 95 percent confidence levels for estimated deaths attributed to influenza in Table 1.

The History of Serious Criticism of the CDC’s “Flu” Death Numbers

There is a long history of serious criticism of the CDC’s “flu” death numbers by medical scientists and others. The most prominent critic is Peter Doshi, currently a professor at the University of Maryland and an associate editor at the British Medical Journal.

Citing the results of actual laboratory tests of deceased patients, critics of the CDC’s flu death numbers such as University of Maryland Professor Peter Doshi have argued that pneumonia deaths are due to a range of different viruses, bacteria, other pathogens, and even toxins, rather than predominantly influenza as implied by the CDC’s influenza deaths model. The output of this model appears to be the basis of the baseline “flu” deaths numbers used in most popular and public policy discussions of COVID-19 deaths — although the leading causes of death report number may also be used.

The Reason for the Large Difference Between the FluView and Leading Causes of Death Numbers

The US CDC documents and web site are frequently unclear and even contradictory as in the case of these grossly contradictory totals of deaths from pneumonia and influenza. This makes it difficult to be certain of the cause for the difference. Nonetheless, the technical notes for each document — FluView and the leading causes of death — give a highly probable reason.

The leading causes of death report uses the language “the underlying cause of death” (sometimes abbreviated UCOD) whereas the FluView web site uses the language “a cause of death”. The leading causes of death report, the smaller number of deaths, appears to count the number of deaths where pneumonia or influenza is listed as the underlying cause of death (Page 74, National Vital Statistics Reports, Vol. 68, No. 6, June 24, 2019).

Death certificates frequently have multiple causes of death. One of these is assigned as the underlying cause of death. This may be quite arbitrary in some cases. Indeed the concept of “underlying cause of death” may not be well defined for some deaths because the aged may develop multiple health problems in parallel that are fatal in combination.

In contrast, the FluView site, the much larger number of deaths, appears to count deaths where pneumonia or influenza is listed as “a cause of death,” even if it is not the “underlying cause of death.”

The Rules for Assigning the Underlying Cause of Death Before COVID-19

Prior to 2020 and COVID-19, most pneumonia deaths did not list pneumonia or the pneumonia-causing pathogen if known as the underlying cause of death. This will be discussed in detail below. The only common partial exception was HIV/AIDS where pneumocystis carinii pneumonia (a common fungus) was often the immediate cause of death and the Human Immunodeficiency Virus (HIV) is almost always listed as the underlying cause of death. However, HIV is not the pneumonia-causing pathogen which is the pneumocystis fungus. Instead, most pneumonia deaths, those included in the FluView numbers but not included in the leading causes of death numbers, were attributed to a cause such as a chronic lower respiratory disease, heart disease, cancer, even accidents, and other usually pre-existing conditions as the underlying cause of death.

The CDC follows the World Health Organization (WHO)’s definition of the underlying cause of death. WHO defines the underlying cause of death as “the disease or injury which initiated the train of morbid events leading directly to death, or the circumstances of the accident or violence which produced the fatal injury” in accordance with the rules of the International Classification of Diseases (ICD).

In the United States, the underlying cause of death is listed last in the list of causes of death in part I of the death certificate. The immediate cause of death is listed first. Part 2 lists other conditions that are considered contributing factors but somehow not causes. Pneumonia is often the immediate cause of death in part 1 of the death certificate.

In principle, death certificates and the assignment of causes of death including the underlying cause of death is governed or at least guided by the CDC’s Medical Examiners’ and Coroners’ Handbook on Death Registration and Fetal Death Reporting (2003 Revision). This one-hundred and thirty-eight (138) page manual actually provides very limited guidance on how to assign the underlying cause of death in cases where pneumonia is present. Page twenty-five (25) has the only detailed discussion of deaths involving pneumonia:

Although the CDC’s Medical Examiners’ Handbook 2003 gives little specific direction on deaths involving pneumonia, it references several books and articles edited or authored by Randy Hanzlick, M.D., now retired Chief of the Fulton County Medical Examiner’s Office and former pathologist with the CDC, including Cause of Death and the Death Certificate: Important Information for Physicians, Coroners, Medical Examiners, And the Public, Randy Hanzlick Editor (2006), College of American Pathologists (the reference seems to have been updated to the year 2006 since the original release of the handbook in 2003) which discusses the cause of death for pneumonia cases in more detail notably on pages 89 and 90:

Pneumonia

Pneumonia is often a nonspecific process that occurs as the terminal event in someone who dies of a more specific underlying cause of death, such as congestive heart failure resulting from ischemic heart disease. In such cases, the specific underlying cause of death should be included in the cause-of-death statement.

Pneumonia is often designated as either community acquired or hospital or institution acquired (nosocomial). If the community- or institution-acquired nature of the pneumonia is known, the cause-of-death statement should include an indication of which one applies.

The specific bacterial, viral, or other infectious agent, if known, should be cited in the cause-of-death statement.

Relevant risk factors should also be cited in the cause-of-death statement, as might occur in an alcoholic who develops tuberculous pneumonia. Only in those instances where pneumonia has caused death and there is no known underlying cause or risk factor should the underlying cause of death be stated as “Pneumonia,” being sure to specify the infectious agent, if known, or specifying that a specific etiology is unknown, if such is the case.

Emphasis Added

And on page 113 of Cause of Death and the Death Certificate by Randy Hanzlick, dementia, cerebrovascular disease, cardiac disease, and lung disease are all listed as common underlying causes of death in cases of deaths due to pneumonia:

Thus, traditionally, pre-2020 and COVID-19, pneumonia deaths were frequently assigned a non-pneumonia underlying cause of death, usually a pre-existing condition and not the pneumonia-causing pathogen such as the influenza virus or SARS-COV-2, in common medical practice. Based on the technical notes these pneumonia and influenza deaths would be included in the FluView death numbers but not in the leading causes of death report.

Comparing COVID-19 Death Numbers to the Pneumonia and Influenza Death Numbers and Estimates from Previous Years

As shown above, the CDC has at least three (3) different pneumonia and influenza death numbers and estimates: the Leading Causes of Death Report (about 55,000 deaths per year, about two percent of annual deaths from all causes), the FluView graph and underlying data from the NCHS (about 188,000 deaths per year, six to ten percent of annual deaths from all causes, before 2020), and the influenza death model estimates that range from 12,000 to 61,000 deaths per year with the best estimate close to the number of pneumonia and influenza deaths in the leading causes of death report. Are any of these the proper baseline for comparing COVID-19 deaths to prior years or should some other number or estimate be used?

In the absence of the RT-PCR and antibody tests for the SARS-COV-2 virus, most COVID-19 deaths would have been unexplained pneumonia deaths lacking a laboratory test confirming influenza or other known pathogen. Possibly, some COVID-19 deaths would have been listed as heart attacks or strokes, those COVID-19 deaths attributed to the blood clots and other blood-related anomalies currently blamed on COVID-19, or even some other causes. The rest of this article will focus on the pneumonia deaths which would probably comprise most of the COVID-19 deaths in the absence of laboratory tests.

The US CDC’s April 2020 guidelines for reporting COVID-19 deaths clearly direct physicians and others not to list chronic obstructive pulmonary disease (COPD) as the underlying cause of death in COVID-19 cases, moving it to Part 2 of the death certificate reserved for “non-cause” contributing factors, which differs dramatically from medical practice prior to 2020 as described in Randy Hanzlick’s book and implicit in the FluView pneumonia and influenza deaths data.

In some cases, survival from COVID–19 can be complicated by pre-existing chronic conditions, especially those that result in diminished lung capacity, such as chronic obstructive pulmonary disease (COPD) or asthma. These medical conditions do not cause COVID–19, but can increase the risk of contracting a respiratory infection and death, so these conditions should be reported in Part II and not in Part I.

NVSS: Vital Statistics Reporting Guidance, Report 3, April 2020, Page 2, Paragraph 3

This guidance also gives a specific example of a COVID-19 death with COPD relegated to Part 2:

Although other causes of death that are often given as the underlying cause of death in pneumonia cases on pre-2020 death certificates are not explicitly identified in the April 2020 guidance document, it seems probable most physicians would move these pre-existing conditions to Part 2 and not list them as the underlying cause of death for COVID-19 based on the April 2020 CDC guidance document. Note that COPD would fall under the category “lung disease” in the list below from Randy Hanzlick’s Causes of Death and the Death Certificate:

Thus, COVID-19 deaths since the April 2020 guidance are probably roughly comparable to the FluView deaths, the larger number, the 188,000 pneumonia and influenza deaths per year. The language “roughly” is used because the April 2020 guidance appears to strongly encourage physicians and others to assign COVID-19 as the underlying cause of death in any death where COVID-19 is detected by tests or perhaps even just suspected, raising the possibility that heart attack and stroke deaths might be wrongly classified as COVID-19 deaths as well as the traditional pneumonia and influenza deaths that would be listed in the FluView data. These would presumably be misclassified as the COVID-19 deaths exhibiting the mysterious blood clots and other blood-related problems reported in some COVID-19 cases and deaths. Thus, the FluView death numbers may represent a lower bound on COVID-19 deaths rather than an exact baseline — unfortunately.

Ealy et al have raised the question whether the CDC complied with the Paperwork Reduction Act (PRA) and Information Quality Act (IQA) requirements in issuing the April and earlier March COVID-19 death certification guidelines, apparently without submitting these for public comment through the Federal Register as Ealy and co-authors claim is required by these federal laws.

Conclusion

Thus, due to the guidance on the death certificates from the CDC in April 2020, COVID-19 deaths on death certificates appear comparable to the larger FluView death numbers — or even larger numbers if heart attacks, strokes or other blood coagulation related deaths with a positive test or clinical diagnosis are being classified as COVID-19 deaths.

The CDC’s documents and web site are remarkably unclear, contradictory, and confusing for public health and scientific information presented to the general public, busy doctors and other medical professionals, or even research scientists — as previously noted by Peter Doshi and others.

(C) 2021 by John F. McGowan, Ph.D.

About Me

John F. McGowan, Ph.D. solves problems using mathematics and mathematical software, including developing gesture recognition for touch devices, video compression and speech recognition technologies. He has extensive experience developing software in C, C++, MATLAB, Python, Visual Basic and many other programming languages. He has been a Visiting Scholar at HP Labs developing computer vision algorithms and software for mobile devices. He has worked as a contractor at NASA Ames Research Center involved in the research and development of image and video processing algorithms and technology. He has published articles on the origin and evolution of life, the exploration of Mars (anticipating the discovery of methane on Mars), and cheap access to space. He has a Ph.D. in physics from the University of Illinois at Urbana-Champaign and a B.S. in physics from the California Institute of Technology (Caltech).