Is this a cure, or is this a disease?

—Chris Cornell

Introduction to the Chapter

Public health, at its core, is about ensuring the health of groups of people. It does this through many ways and organizations. In this chapter, we will first talk about why public health matters and how it has improved our lives. We will review some of the greatest achievements in public health and look at how the responsibilities are divided among federal, state, and local public health agencies. We will discuss how public health laws are passed and why they can be controversial. Finally, we will review some of the specific areas within the larger field of public health along with some potential careers.

Learning Outcomes

After reading this chapter, students will be able to:

1. Describe the biggest achievements in public health
2. Review the roles of the federal, state, and local governments in public health
3. Explain the process of how public health laws are passed
4. Discuss potential careers related to public health

Key Terms

The following key terms will be introduced in this chapter.

• Intervention: Any activity taken with the goal of improving the health of the public.
• Risk factor: An exposure or behavior that increases the chance of developing a disease.
• Health outcome: A result occurring because of an intervention.
• Epidemiology: The study of health and disease and how these are distributed across the population.
• The three P’s of public health: Preventing disease, prolonging life, and promoting health.
• The three core functions of public health: Assessment, policy development, and assurance.
• The three branches of the federal government: Executive, legislative, and judicial.

Disease in Focus—Heart Disease

In this chapter, we will focus on the top cause of death in the United States, cardiovascular disease also known as heart disease. Heart disease has many different causes and occurs over a long period of time, making it one of the most difficult diseases to eliminate. Some of the factors that are known to contribute to heart disease are a diet with high levels of saturated fat, sedentary lifestyle, high cholesterol, high blood pressure (hypertension), and the use of tobacco. Often, heart disease involves atherosclerosis or hardening of the arteries. Fats and other materials, collectively referred to as plaque in the blood, can accumulate on the walls of the arteries. Over time, this can accumulate to the point that a blood clot can cause a blockage of one or more arteries supplying blood to the heart, which can result in a heart attack, when blood flow to the heart is blocked. Whether someone survives and the extent of the damage depends on how long they are without blood supply to the heart. Closely related is a stroke, which is when an artery to the brain is blocked.

Section 1: Why Does Public Health Matter?

Before we can talk about the details of public health, it is important to first understand why it matters. To better understand why it matters, let’s first look at how lives and health in the United States have changed in the last 120 years. For many people living in the year 1900, life was hard. Most people were farmers, with nearly 6 million farms across the country. However, the average size of a farm was less than 150 acres, and there were no tractors or other motorized equipment to help you work the land. If you did not work as a farmer, other common jobs included mining, factory workers, blacksmiths, and teachers. With few laws regarding workplace safety, tens of thousands of workers were injured or killed each year. On average, most people working full time could earn between $400 and $600 a year. Families were large, with women usually having three to four children. Most children only attended school for a few years, with almost all high school aged children either returning to help on their family farm or getting a job to help support their family. Only 11% of high school aged children attended school (U.S. Census Bureau, 1950).

The state of medicine in 1900 was almost unrecognizable compared to today. A scientific approach to medicine, while nearly universal today, was uncommon in 1900. Many practicing physicians still were using treatments based on medical advances from hundreds of years earlier. Hippocrates, a Greek physician who lived around 400 B.C., was one of the first to discuss health and disease in humans being based on four humors, blood, phlegm, yellow bile, and black bile. The idea was that these must be balanced in just the right amount, and if an imbalance occurred in the humors within the body, disease was the result. Therefore, treatments were meant to help restore the proper balance, and led to treatments that seem shocking today. One common treatment was bloodletting, based on the idea that too much blood in the body was causing an imbalance in humors. Harmful chemicals like mercury were used to induce vomiting, again with the goal of restoring the balance of humors (Hendry, 2021). It is safe to assume that most people that recovered did so in spite of these treatments, and not as a result of them. There were no vaccines or antibiotics available, and most treatments consisted of things like alcohol, opium, or cocaine disguised as a cure-all treatment in a bottle.

Considering this, it is not surprising to learn that life expectancy was short for people living at this time. Only around eight in 10 children born in 1900 would make it to their first birthday. Life expectancy was only 46 years for men and 48 years for women. For African Americans, like expectancy was a stunning 33 years. Many people died from common infections or diseases that are easily treatable today. As described above, even the treatments proposed by physicians could often exacerbate an illness or lead to death.

The change in medicine and human health between 1900 and today is truly amazing. Less people are killed in the workplace today than in 1900, despite there being 100 million more people working. Infant mortality has been reduced from 10% to less than 0.5%. Deaths from diseases like cancer, heart disease, and infectious diseases have all dropped sharply. Vaccines save millions of people from illness and death every year. Life expectancy has risen sharply to over 76 years on average. These changes in the number of years we live and the quality of our health in those years are mainly due to advances in two areas, medicine and public health. One of the simplest ways to see the benefits of public health is to look at the changes in life expectancy for people today compared to 1900 (Figure 1.1).

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While these advances in health and life expectancy are from both medicine and public health, these two areas benefit people in different ways. Medicine is focused on an individual patient and their specific health needs, while public health is focused on the health needs of a larger group. When you visit a physician, they make a diagnosis and treatment suggestion based only on you. In public health, the approach must be different, as the “patients” might be an entire town, state, or even a country. It is important to remember that public health is focused on efforts that will benefit the most people in a large group and is often more focused on ways to prevent diseases instead of treating them once they occur.

In addition to increasing our life expectancy, public health impacts many areas of our day-to-day lives, often in ways we rarely think about. Let’s look at an average day for most people in the United States to see some of the ways that public health impacts our lives. Most people will wake up in the morning and first take a shower or brush their teeth. Public health laws and regulations help to ensure that the water coming out of your faucet or shower head is safe. If you eat breakfast or make coffee, public health laws ensure that the food was properly prepared and will not cause you to get sick. Drinking water standards ensure you can safely drink your coffee without ingesting harmful chemicals or other substances. As you walk out of your home, the air you breathe contains lower levels of harmful pollutants due to clean air laws passed decades ago. If you get into a car and drive to your work, roadway design and regulations along with many vehicle safety advances make your trip to your work much safer than in the past. Once at work, your chances of getting injured or killed are much less than in the past, due to workplace safety regulations. On and on, throughout your day, you are impacted by public health in many seen and unseen ways. It adds up to a much healthier environment for everyone and contributes to an improved quality of life. So let’s take a look at how we define public health and some of the greatest achievements over the last 120 years.

Section 2: What Are the Greatest Achievements in Public Health?

Public health can be summarized as a focus on the three P’s for a large group of people:

• Preventing disease
• Prolonging life
• Promoting health

The focus in public health is on creating the proper conditions to ensure that these three P’s can occur. This occurs through the same general process. First, it is important to identify the problem. After that, the cause of the problem must be understood. Related to this is identifying risk factors, and these are conditions or behaviors that increase the chances of developing a disease or illness. Next is implementing an intervention, things that are done in public health to reduce the cases of a disease. This might be a treatment or something like education to help people better understand the symptoms of an illness. A health outcome is the result that occurs following the intervention. After the intervention has been tried and evaluated to see if it will work, the final step is the implementation of the intervention on a larger scale to try to reduce the problem. Below is a summary of the some of the interventions that have been most successful in the United States.

Control of Infectious Diseases

One of the most influential achievements in public health is the improved methods for controlling infectious diseases. In 1900, the spread of infectious diseases was not well understood, and therefore not easily controlled. Sanitation was lacking in most cities, as animal and human waste was often dumped in streets or nearby water sources resulting in the spread of many diseases. There was also little effort to control animal pests or insects that spread diseases, such as rats or mosquitoes (Figure 1.2). As sanitation improved along with better animal and insect control, there has been a large decrease in the spread of many infectious diseases. While many infectious diseases were among the top causes of death in 1900, those have today been greatly reduced. The discovery of antibiotics has also helped to control many bacterial diseases, including reductions in tuberculosis.

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The impact of many of these changes was seen in the COVID-19 pandemic. Information on the viral pathogen was obtained much quicker than in past years, with the complete genetic sequence of the coronavirus determined within several months and the first treatments and vaccines available and distributed within a year of the virus being discovered.

Safer and Healthier Foods

In the early 1900s, the methods of microbial contamination of food were still not understood. Advances in areas like food refrigeration and better techniques for preparing food have reduced the number of foodborne illnesses. Today, our food is commercially prepared using sterilized surfaces along with better monitoring of food spoilage to prevent illness from foods that are purchased. Nutritional content is also better understood, with the importance of vitamins and fiber better understood. The impact of certain foods on non-infectious diseases, like obesity, diabetes, and heart disease, is also much clearer than in the past. This means that foods eaten today are less likely to cause you to get sick and also healthier than in the past.

Recognition of Tobacco Use as a Health Hazard

Tobacco use was still low in the early 1900s, but it spiked after the world wars, when soldiers were provided cigarettes as a part of their daily ration. Millions of men came back addicted to tobacco, and from the 1930s to 1960s, there was a huge increase in smoking rates. We now have a better understanding of the health impacts from tobacco, including higher rates of lung and other cancers, emphysema, and respiratory diseases. The links between tobacco use and heart disease are also well understood today. The non-smokers movement, a focus on preventing the health impacts from tobacco on second-hand non-smokers, has also led to increasing limitations on where smoking is allowed. Many institutions, including college campuses, are now designated as tobacco free (Figure 1.3). This increase in our knowledge of the health impacts, along with taxes and control measures, has resulted in a drop from a peak of nearly 50% smoking rate among adults to today around 12%.

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Reduction in Deaths from Non-Infectious Diseases

Heart disease and stroke have been among the top causes of death for around 100 years. The rates of death from these illnesses peaked in the 1950s, as up until this time very little was understood about the causes of these illnesses. Several large studies in the 1950s and 1960s showed the impact of things like high blood pressure, high cholesterol, and smoking on cardiovascular disease, the general term for the buildup of plaque on arteries, which can result in a blockage of blood flow to the heart (heart attack) or brain (stroke). As these causes were better understood and drugs became available to treat high blood pressure and cholesterol, the rates of heart disease and stroke have declined by more than 60% from their peak.

If you are interested in learning more about some of the other achievements identified as the 10 greatest, follow this link: https://www.cdc.gov/mmwr/preview/mmwrhtml/00056796.htm.

Section 3: What Is the Role of Government in Public Health?

As we have discussed, the general approach in public health is to first identify a problem, then try to find a solution to the problem that can be implemented and then check to see if it is working. This is usually summed up as the three core functions of public health: assessment, policy development, and assurance. The main work in public health is performed by government agencies at three different levels, federal, state, and local. Each level has specific tasks and goals related to public health, with very different groups of people they are focusing their interventions on.

Public health in the United States is coordinated at the federal level. While there is no direct mention on ensuring health of people in the U.S. constitution, many of the other requirements, including interstate commerce and taxation, have been used to justify a coordinating organization at the federal level. This is the Centers for Disease Control and Prevention, often referred to as the CDC. The CDC has its roots as the Marine Hospital Service, established in 1798 to provide healthcare to merchant seamen. This was expanded to include additional diseases as more popped up in the 1900s, specifically work to control infectious diseases like yellow fever, malaria, and smallpox. It was not until after World War 2 that the CDC became focused on being the central authority for all public health in the United States. Today, the CDC is headquartered in Atlanta, GA (Figure 1.4) with around 15,000 employees and a budget or around 11 billion dollars (about $34 per person in the United States) each year. The main responsibilities are to set the public health agenda for the country and also to ensure that states and local public health agencies have assistance when they need it. They provide surveillance for many different diseases, published in the Morbidity and Mortality weekly report (MMWR). The CDC also is responsible for administering funding to state and local public health agencies. While the CDC works in a non-regulatory role, other federal organizations like the Food and Drug Administration are used to approve the use of specific food production or pharmaceutical drugs.

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Some of the benefits and challenges of having a central public health authority have been seen during the COVID-19 pandemic. Some of the benefits of having a national public health authority during a pandemic is that everyone has a source to look to for information regarding the disease and how to prevent it. This was seen during the pandemic with traffic to the CDC website increasing 241% in 2020 from the previous year with almost 4 billion page views. The CDC was able to use their resources to make sure people understand the illness and ways that it could be spread and how to best prevent it. They also were able to communicate changes as more was learned about the disease or new vaccines became available.

While there are many benefits to the CDC being the main organization coordinating the countries response to COVID-19, there were also challenges from this approach. First was that changes in messaging or information led to confusion many times during the pandemic, with one example being the benefits of masking to prevent the spread of COVID-19. Early in the pandemic, the CDC suggested that masking was not necessary, but as new information was gained, they changed the guidance to strongly advising the use of masks as one of the best ways to prevent the spread of the coronavirus. These sorts of changes can be confusing and lead to less confidence in the subsequent information released by the organization. The other challenge was that different regions of the country were impacted to different levels and at different times during the pandemic. This meant that the CDC was trying to provide guidance to regions that might have very high rates of disease and hospitalization while other parts of the country had low transmission and disease rates. This again led to confusion for some people as to which guidance best applied to them at the time. This situation highlights the importance of state and local public health departments, which we will discuss next.

Due to a lack of specific language on health in the constitution and the 10th amendment means that the primary responsibility for public health is left to individual states. State public health agencies have responsibilities that are more focused on their specific state needs, but also often take guidance and funding from the CDC. They are responsible for collecting health data from local public health agencies and then reporting it to the CDC for the MMWR. They also often serve as a central laboratory and testing facility. For example, the testing of blood for lead levels is more efficiently done if there is one central location at the state level instead of each local city or county having to purchase their own testing equipment.

The day-to-day functions of public health are often done at the local level. Setting up health clinics, ensuring that streets are clean, administering vaccines and many other essential functions of public health are done at the local level with coordination and guidance from both the state and federal level. While most of the public health is done by governmental groups, it is important to also mention the role of non-governmental organizations (NGOs). These are often non-profit groups that have a specific disease or illness as a focus. Some examples may be philanthropic organizations, such as the Bill and Melinda Gates Foundation, which has provided grants to improve the health in communities around the world. Or they may be fundraising to cure a specific disease, like the American Cancer Society or the Alzheimer’s Association. In addition to funding research on cures or public health improvements, they can also be involved in crafting public health policy changes.

Let’s return to our disease in focus for this chapter, heart disease, and look and how federal, state, and local public health organizations along with NGOs coordinate to decrease the impact from this disease on the U.S. population using the three core functions of public health. At the federal level, the CDC is involved in many different surveillance methods (assessment) to determine how many people are developing heart disease each year. This is done by gathering information from hospitals and also administering health surveys to a sampling of people around the country. Assessment work at the state and local level would involve gathering data on the number of people experiencing heart disease. The assessment could also involve determining the number of people that have risk factors known to be associated with the disease, in this case high blood pressure, high cholesterol levels, or tobacco usage. Once the extent of the problem is determined, policies are needed to reduce the occurrence of heart disease. For heart disease, there are many different areas that contribute to the disease, so this could include federal guidelines on proper diet and exercise, restrictions on tobacco usage, or guidelines on healthy ranges for blood pressure. At the state level, policies might include increased taxes on tobacco or alcohol, which are both known to increase the chances of developing heart disease. It may also include increased funding for public trails or exercise promotion. Similar policies can be developed at the local level and could include things like organized free exercise classes, indoor smoking bans, and other things that would impact the heart disease risk factors in the local community. Finally, assurance, which asks are these things making a difference in the impact of heart disease? This could be done through additional federal research funding on the disease or providing additional support for people who have made lifestyle changes at the state of local level. NGOs, for example, the American heart association, are also important due to their ability to fundraise money to support research and creating additional publicity for interventions to reduce the impacts from heart disease and stroke.

Section 4: How Are Public Health Laws Passed?

The federal government has three main branches, the executive, legislative, and judicial. The legislative branch is responsible for writing and passing the laws. Within this branch, it is the U.S. Congress that is responsible for creating new federal laws. There are two chambers of Congress: the U.S. House of Representatives and the U.S. Senate. Any member of Congress can propose a new law, referred to as a bill. Once a bill is brought forward in either part of Congress, it is assigned to a committee that researches the bill, revises it, and decides whether to release it to the full House or Senate for a vote. Once a bill that is voted on and approved, it is then sent to the other chamber of Congress, where it goes through a similar process of being assigned to a committee, researched, and amended. If both chambers can pass the bill, they must work together to revise any differences between the two versions. Once the differences are resolved, both chambers of Congress again vote, this time on the same revised bill. If it is approved by both chambers, it is sent to the president, who can either sign the bill into law or veto it. If there is enough support in Congress, a presidential veto can sometimes be overridden by Congress. After passage, the law is then interpreted by the judicial branch, which determines whether the law is compatible with the U.S. Constitution and applies it to individual cases.

States are more varied in their approach, with some using a very similar process to the federal government while others use different methods to prepare and approve new laws. State laws will only apply to people who are in that state. The doctrine of preemption says that anytime there is a conflict between state and federal law, the federal law prevails. It also says that state laws cannot deny to people any rights enshrined in the U.S. Constitution. Usually, if a state law gives its citizens more rights than the federal law, the state law will prevail.

Historically, the first documentation of births and deaths along with some reporting of diseases was done in Massachusetts, starting in the 1840s. This eventually became the model that was adopted by other states through the 1800s. One of the first federal laws related to public health was the Immigration Act of 1891, which all immigrants entering the United States to undergo a health examination (Figure 1.5). In 1906, the Federal Meat Inspection Act and Food and Drug Act were passed by Congress, allowing the U.S. Department of Agriculture to inspect meat and preventing adulteration and misbranding of foods and drugs. It was not until 1916 that the first school of public health was established at Johns Hopkins University. In 1938, the Federal Food, Drug and Cosmetic Act was passed, which established the Food and Drug Administration and required it to review safety and efficacy of products before they could be approved for sale. The early 1970s saw many new federal agencies and laws which would have a huge impact on the health of people in the United States. The U.S. Environmental protection agency was established along with passage of the Clean Air and Clean Water Acts, which set standards for pollution and preventing dumping wastes into local waterways. In 1980, the Comprehensive Environmental Response, Compensation and Liability Act was passed, which gave the Environmental Protection Agency (EPA) authority to clean up sites contaminated with hazardous wastes.

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While the scope of public health laws and federal and state levels are often similar, this is not always the case. In the last 20 years, there have been several examples where federal and state regulations and laws have differed. The first is regarding pollution standards. While the EPA has established basic standards on things like vehicle emission standards, some states have passed laws which have even more stringent rules for the levels of pollutants that can be emitted. Another area with differences between federal and state law is in regard to legalization of marijuana for medical and recreational use. At the federal level, marijuana is still regulated as an illegal drug; however, over the past 15 years, states have begun to legalize it for medical and then recreational use. There are now 37 states that have legalized marijuana for medical use and 21 for recreational use. This discrepancy has resulted in some unique challenges for businesses selling marijuana and associated products, including challenges with funding, production, and transportation of products.

Often, one of the main goals of public health laws is for the common good, which is also one of the reasons why public health laws can at times be controversial. The first way that public health laws can be controversial is that they limit individual freedoms. We can look no further than the masking mandates associated with COVID-19 to see how laws meant to prevent the spread of disease can be seen as limiting personal choice. Early in 2020, it became clear that the virus causing COVID-19 was most often spread through the droplets expelled from a person coughing or sneezing, and so the CDC reversed its initial guidance and recommended that people wear masks whenever around other people. Many states implemented mask mandates that required the use of masks if someone was going to a store or any other public place. Almost immediately, protests spread through social media and some television networks claiming injustice that people no longer could choose for themselves whether to wear a mask or not. This issue has also been raised by other public health laws like requiring seat belts to be worn and motorcycle riders to wear helmets.

The other controversial aspect of public health laws is that the cost of implementing the laws is often not paid by the ones who benefit. Usually, it is businesses that are saddled with additional expenses due to public health laws, while it is others who benefit from them. One example related to safe foods is the requirement that milk and juice be pasteurized before they are sold. These beverages can sometimes contain harmful bacteria in their raw form, and so during bottling, the milk or juice is very briefly heated to a high temperature ensuring that the pathogens are killed before it is distributed to stores to be sold. Milk and juice manufacturers must pay for the pasteurization equipment to be installed, while it is the consumer that benefits from having safer milk and juice to drink. This is one reason that businesses can at times be more resistant to passage of new public health laws.

Section 5: What Are the Careers Related to Public Health?

Public health can be divided into many different areas that all contribute to the overall goals of reducing disease in the population. In this section, we will briefly discuss each area along with highlighting a career that is associated with it.

Environmental public health—This area focuses on the environment and how it contributes to public health. Our health is greatly impacted by the air and water quality in our environment. Examples of careers in environmental public health include providing testing of air or water quality for state or local public health agencies or writing impact assessment documents on the environmental impacts of new infrastructure or development projects.

Health policy—As we have discussed in this chapter, once an intervention is proposed, a policy is often needed to implement it. This is done by individuals who have specific skills in writing health policies. Another job related to health policy is the researchers who find the data related to health policies.

Behavioral health—Human behavior plays a large role in whether we make positive or negative decisions about our health. Those who specialize in behavioral health try to better understand why someone chooses to eat a healthy diet or exercise, or what behavior changes can get someone to quit smoking or using tobacco. Jobs related to this area could include genetic or health counselors who are able to help individuals choose decisions that will improve their health or help them better understand diseases they are more susceptible to.

Epidemiology—The first core function of public health is assessment, and this is often done through epidemiology. This is the study of the distribution and spread of diseases. Epidemiologists are needed at all three levels of public health. Thousands of epidemiologists are employed by the CDC, but they are also needed at the state and local level to investigate outbreaks and ensure the proper health conditions are being met by businesses.

Research—Public health research is important to develop new treatments or procedures and also to ensure that they work using scientific approaches. There are many laboratories at the CDC and colleges and universities that study specific questions related to public health. This might be investigating new treatments and pharmaceutical drugs or recruiting participants for clinical trials.

Biostatistics—Once data are generated, it is often difficult to know if a difference between groups of data is actually meaningful. This is where statistics are essential in public health. These analyses can help determine whether there is a meaningful difference after a treatment or intervention is used. Biostatisticians are able to use the appropriate analyses to help determine the significance of public health findings.

Specific populations—In some cases, individuals specialize in the health of specific populations or groups. For example, focusing on maternal or child health, or the health of specific ethnicities. These are important groups that have at times been excluded from public health data collection in the past, so there is an increased emphasis to make sure that surveys and other data collection methods are now using a true sample from the population.

There are many exciting opportunities in public health, and most of these fields are estimated to be growing over the next 10 years. With many people currently in these positions retiring, there will be new opportunities available for those who are interested in having a career ensuring the health of the people in their communities. More information on careers in public health can be found at https://www.publichealth.org/careers/ and https://www.cdc.gov/stem/careers/index.html.

Chapter 1 Summary

In this chapter, we first learned why public health is important and how it is involved in our lives, often in ways we do not directly see. We looked at some of the greatest achievements in public health and how public health responsibilities are divided among the federal, state, and local governments. We reviewed the process of how a law is passed and reviewed some important public health laws in our history. We also discussed why public health laws can at times be controversial, and how they can differ between the federal and state level. Finally, we covered some of the areas under the umbrella of public health along with some careers associated with the various sections of public health.

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Image Credits

Fig. 1.1: Copyright © 2024 by Our World in Data (CC BY 4.0) at https://ourworldindata.org/grapher/life-expectancy?time=earliest..2021&country=~USA.

Fig. 1.2: CDC, https://commons.wikimedia.org/wiki/File:DDT_spray_1958.jpg, U.S. Department of Health and Human Services, 1958.

Fig. 1.3: Copyright © 2019 by Artaxerxes (CC BY-SA 4.0) at https://commons.wikimedia.org/wiki/File:Tobacco_ban_sign_entrance_Northern_Vermont_University_Lyndon_VT_August_2019.jpg.

Fig. 1.4: James Gathany/CDC, https://commons.wikimedia.org/wiki/File:CDC_Headquarters_PHIL_10693.tif, U.S. Department of Health and Human Services, 2013.

Fig. 1.5: NIAID, https://commons.wikimedia.org/wiki/File:Ellis_Island_Public_Health_Service_Physicians_(7844875428).jpg, 1910.