CHAPTER 1
THE COVID-19 PANDEMIC: A PORTRAIT OF AN EPIDEMIC

LEARNING OBJECTIVES

1. Appreciate and explain the history of the COVID-19 pandemic.
2. Understand disease transmission and the chain of infection and how this can be altered to protect the public.
3. Explain basic principles of infection and disease transmission.
4. Describe the function of vaccines.
5. Explain how self-interests in government can hinder public health efforts to control the spread of infectious diseases.
6. Describe examples of corporate interests that overshadowed public health efforts to control COVID-19.
7. Using COVID-19 as an example, articulate how epidemics magnify racial and ethnic disparities in nations such as the United States.

The following is an excerpt taken from a speech delivered by President Barack Obama, in the White House, to an assembly of global health leaders. The excerpt begins by referring to recent global pandemics such as Ebola, H1N1, and SARS.

Each time, it's been harder than it should be to share information and to contain the outbreak. As a result, diseases have spread faster and farther than they should have - which means lives are lost that could have been saved.

-President Barack Obama, September 26, 2014

Overview

The last case of smallpox was diagnosed in 1977. The disease caused an estimated 300 million deaths over at least a thousand years, so this final diagnosis represents a milestone in public health practice. The milestone was achieved through one of public health's greatest assets: vaccination! So, it would seem that vaccines will solve everything related to global pandemics. If only this were true! The sobering reality is that Edward Jenner's pioneering work on the smallpox vaccine occurred more than 200 years before the disease was eradicated. The lesson that should have been learned from the globally coordinated smallpox vaccination campaign was that people - and even entire governments - are bound to resist vaccination, regardless of the potential consequences. The World Health Organization (a global entity that is widely recognized for being the world authority on the prevention and control of infectious disease) ultimately mobilized health workers to enter even the most remote and culturally unique areas of the planet to convince people to take the vaccine being offered to them at no cost. Sadly, this global smallpox vaccine campaign lasted more than 11 years and was fraught with conflict at the local level in nation after nation.

Now, let's fast-forward to 2021, when healthcare workers around the world were assigned the task of entering remote and culturally unique areas of the planet to convince people to take the vaccine being offered to them at no cost. This time, it was a vaccine against COVID-19. Sadly, populations were not universally glad to have this vaccine; millions of people refused it, despite ample evidence that death from COVID-19 was approximately 11 times more likely among the unvaccinated than the fully vaccinated. This level of refusal was, of course, history repeating itself. But stark differences existed between smallpox vaccination campaigns and vaccination campaigns against SARS-Cov-2 (i.e., COVID-19). With COVID-19, the very same discussions healthcare workers were having with people in isolated tribal villages in Sierra Leone, for example, were also occurring in most U.S. states! Despite an overwhelming level of access to education, COVID-19 vaccine information, and published evidence of the vaccine's safety records, millions of U.S. residents were asking questions such as, "Why should I trust the contents of this vaccine?" and "How do I know this will not give me COVID?" In short, massive uptake of the vaccine did not happen.

As the Delta variant of COVID-19 emerged, it had a huge advantage: many unvaccinated people also were not wearing masks. Due to behavioral factors that were not rectifiable, these two very simple public health measures (vaccination and mask wearing) failed to protect the public. Consequently, hospitals continued to be overwhelmed with COVID patients, workforce productivity was slowed, supply chains were crippled, and economies worldwide slowly imploded under the constant strain of a pandemic that could have ended in record time.

two very simple public health measures (vaccination and mask wearing) failed

This chapter is not about the history of COVID-19, nor is it about the host of blunders and mistakes made in terms of public health response. Instead, it uses COVID-19 as an example of how public health practice can successfully control the spread of infectious diseases. As the only chapter in this textbook devoted to infectious disease, this topic comes first because controlling epidemics and pandemics is the very origin of public health practice.

As you study this chapter, you will learn basic principles pertaining to the spread and control of infectious diseases. To keep the discussion relevant and timely, each example will be applied to COVID-19. You will also learn a bit about mutation and why, for example, the flu vaccine must be remade and redistributed annually. As the chapter continues, you will come to understand that COVID-19 is not a "once in a lifetime" disaster. Rather, COVID-19 should be viewed as a warning to all humans that our species exists in a fragile balance within a complex web of tiny microorganisms that ultimately can cause massive levels of death and turmoil. Learning to respect this balance and protect it through carefully planned standards of public health practice is an urgent priority for all of us.

All too often public health is taken for granted. The exception is when a nation or the entire world is in the midst of an epidemic or pandemic. Thus, a top priority of public health is the control of infectious disease. If you visualize public health practice as a pyramid, the base is first and foremost the control of rapidly spreading infectious diseases. Indeed, this goal is the origin of public health (see Chapter 2). This book also begins with this chapter because COVID-19 teaches a lesson that should greatly inspire all of us: that "we the people" must have an advanced understanding of what may arguably be the most vital function of local, state, and even federal government: protecting the health of the people. Finally, as this is the only chapter in this textbook devoted to infectious disease, you will learn about the overall principles of disease transmission and control. These principles are more important than COVID-19 per se because it is highly likely that many other life-threatening infectious diseases will emerge in the coming decades (Beeler, 2021).

"we the people" must have an advanced understanding of what may arguably be the most vital function of local, state, and even federal government: protecting the health of the people.

Basic Terminology

Before you read any further in this chapter, it is vital to understand the implied meaning of several terms related to public health practice. The first, of course, is the word pandemic. COVID-19 is correctly referred to as a pandemic because it is a global occurrence - thus, pandemics affect multiple nations and continents. When, however, referring to just one nation (such as Britain, China, or the U.S), it is appropriate to use the term epidemic. Epidemics are local, whereas pandemics are global. Although you may not be used to thinking about the United States as "local," from a global perspective this is very much the case. Because of significant differences between governments, cultures, and the health status of people, it is useful to think about how, for example, one nation differs from another in terms of progress in controlling its local version of any given pandemic. A third term in this regard is endemic. History shows that most nations can eventually reduce the severity of an epidemic to a low and stable level of annual new cases. At that point, the disease causing that epidemic is correctly referred to as an endemic. Sadly, some epidemics reach an endemic level only after several years, or even decades, of public health intervention.

For now, three other terms are vital for you to understand. The first denotes any microorganism having the ability to invade the human body and trigger a disease process: this is a pathogen. A pathogen may or may not be a living cell in its own right. COVID-19 is caused by a virus. A virus is not a living cell. Instead, it is a set of genetic instructions looking for cells to invade so it can carry out these instructions. The next term is immunity. Without immunity to pathogens, humans would quickly perish. Immunity is typically acquired based on the invasion of a given pathogen followed by a successful immune response. It is very much the case, by the way, that your immune system is your lifeline to survival. Immunity to a specific pathogen can also be acquired through the artificial means of vaccination. When a pathogen invades the immune system (or, in the case of vaccines, when the properties of the vaccine enter the body) and the immune system functions properly, the result is the development of antibodies. Depending on the...