The case fatality ratios don’t make any sense.
We have already computed that the USA population is 4.2% of the global population, yet 26.5% of the total number of global deaths have occurred in the USA. Does this make any sense, or could it be that the numbers that we are getting are highly inaccurate?
By Israel Zwick, April 28, 2020
About the author: Israel Zwick holds advanced degrees in biology, science education, and school psychology. He recently retired from working as a school psychologist for the NYC Department of Education. Before that he taught biology and chemistry for 15 years. Prior to that, he worked in the microbiology laboratories of the NYC Department of Health.
It’s Tuesday morning. I look out the window and see that the sun is finally shining. After days of rainy, cold weather, it’s beginning to seem like the end of April instead of the beginning of March. Under normal circumstances, at this time, I would already be showered, dressed, and out of the house. But these aren’t normal times. So I’m still in my pajamas, slowly sipping my cup of morning coffee, and nibbling on my leftover kosher for Passover chocolate macaroons. I’m afraid to step on the scale to find out how much weight I gained over the last few weeks, but I know that my belt has gone up a notch.
The first thing that I do is to ask my smart speaker to play the news. More on the COVID-19 pandemic. So I tell my speaker to stop, I had enough. Then I pick up my smartphone and check my SmartNews App. It seems that the number of “smart” gadgets and “smart” apps are proliferating faster than the virus. The SmartNews app has a tab devoted exclusively to news on the coronavirus. The first thing I see under the tab are the numbers listing the US cases and deaths as well as the global cases and deaths. My first impression on seeing these numbers is that there is an inverse relationship between the number of smart gadgets in circulation and the number of smart people in circulation. That is, they are inversely proportionate. As the number of smart gadgets increases, the number of smart people decreases.
The numbers don’t make any sense to me. The global population is estimated to be 7.8 billion while the USA population is estimated to be 330 million. My smart calculator tells me that the US population is 4.2% of the total global population. The chart tells me that in the USA, there were 56,253 deaths form COVID-19 out of 988,469 confirmed cases. That’s a case fatality ratio of 5.7% in the USA. The total number of global confirmed cases is 3,057, 957. Case fatality in USA out of total global cases is 1.8%. Global case fatality is 211,894 out of 3,057,957 or 6.9%. The number of US deaths compared to global deaths is 56, 253 divided by 211,894, which according to my smart calculator is 26.5%. That means that of all the COVID-19 deaths in 190 countries, 26.5% of them died in the USA. But we have already computed that the USA population is 4.2% of the global population, yet 26.5% of the total number of global deaths have occurred in the USA. Does this make any sense, or could it be that the numbers that we are getting are highly inaccurate?
To try to find an answer to this question, I pulled out my copy of Jekel’s Epidemiology, Biostatistics, Preventive Medicine, and Public Health, Fourth Edition by David L. Katz, MD, MPH, FACPM, FACP, et al., published in 2014. First, I turned to the page, “About the Authors” and I learned the following:
“David L. Katz, MD, MPH, FACPM, FACP, is the founding director of Yale University’s Prevention Research Center. He is a two-time diplomate of the American Board of Internal Medicine and a board-certified specialist in Preventive Medicine/Public Health. Dr. Katz is known internationally for expertise in nutrition, weight management, and chronic disease prevention. He has published roughly 150 scientific articles, innumerable blogs and columns, nearly 1,000 newspaper articles, and 14 books to date. He is the Editor-in- Chief of the journal Childhood Obesity, President-Elect of the American College of Lifestyle Medicine, and founder and President of the non-profit Turn the Tide Foundation….”
I didn’t have to go much further to find some meaningful information. The first chapter is titled “Basic Epidemiologic Concepts and Principles.” On page 8, I found the following:
” Solution of Public Health Problems and Unintended Creation of New Problems. One of the most important insights of ecological thinking is that as people change one part of a system, they inevitably change other parts. An epidemiologist is constantly alert for possible negative side effects that a medical or health intervention might produce. In the United States the reduced mortality in infancy and childhood has increased the prevalence of chronic degenerative diseases because now most people live past retirement age. Although nobody would want to go back to the public health and medical care of 100 years ago, the control of infectious diseases has nevertheless produced new sets of medical problems, many of them chronic. Table 1-1 summarizes some of the new health and societal problems introduced by the solution of earlier health problems.”
It continues with a discussion of immunity:
“Vaccination and Patterns of Immunity. Understanding herd immunity is essential to any discussion of current ecological problems in immunization. A vaccine provides herd immunity if it not only protects the immunized individual, but also prevents that person from transmitting the disease to others. This causes the prevalence of the disease organism in the population to decline. Herd immunity is illustrated in Figure 1-2, where it is assumed that each infected person comes into sufficient contact with two other persons to expose both of them to the disease if they are susceptible. Under this assumption, if there is no herd immunity against the disease and everyone is susceptible, the number of cases doubles every disease generation (Fig. 1-2, A). However, if there is 50% herd immunity against the disease, the number of cases is small and remains approximately constant (Fig. 1-2, B). In this model, if there is greater than 50% herd immunity, as would be true in a well- immunized population, the infection should die out eventually. The degree of immunity necessary to eliminate a disease from a population varies depending on the type of infectious organism, the time of year, and the density and social patterns of the population. Immunization may seem simple: immunize everybody in childhood, and there will be no problems from the targeted diseases. Although there is some truth to this, in reality the control of diseases by immunization is more complex. The examples of diphtheria, smallpox, and poliomyelitis are used here to illustrate issues concerning vaccination programs and population immunity, and syphilis is used to illustrate natural herd immunity to infection.”
Perhaps we should be paying attention to what Dr. David L. Katz is saying. He seems to be making sense out of all the nonsense that is going on around us. It is definitely important to mitigate the spread of the coronavirus and reduce the number of deaths, but it is also important to mitigate the effects of this disastrous global lockdown, which is also costing numerous lives, and will continue to do so long after the novel coronavirus has disappeared. The deaths from undiagnosed cancers, famine, neglected immunizations, and suicides, will continue for years.