Imagine a child born in Philadelphia on July 4, 1776, the morning the Declaration of Independence took final shape a few blocks away. The world she entered was, by any modern measure, brutal.
About one in five infants did not live to see a first birthday. Only about half of children survived to adulthood. Drinking water was a gamble. Childbirth could kill the mother. Yellow fever, smallpox, cholera and tuberculosis were not history; they were neighbors. Average life expectancy hovered in the mid-30s.
A child born today in the same neighborhood can expect to live more than twice as long. Infant mortality has dropped by more than 90 percent since 1900 alone. Polio, measles and diphtheria have been pushed to the margins of memory. In nearly every community, clean water flows freely from taps.
Shared Responsibility
Most Americans grow up assuming all of this. But between those two children lies a quiet revolution delivered not by any single discovery. It’s the output of the cumulative work of an idea, persistently applied across two-and-a-half centuries: that the conditions of human health are a shared responsibility.
“Public health is what we as a society do to assure the conditions of health,” said James Curran, MD, MPH, retired dean of the Rollins School of Public Health at Emory University and former task force lead at the Centers for Disease Control and Prevention’s (CDC) HIV/AIDS division. The definition is intentionally broad. Public health, for instance, is the seat belt in your car, the restaurant inspector who keeps customers from getting sick, the action that took lead out of paint a generation ago.
Women fetch water from a well in New York in this engraving from 1799. Open sources of water were breeding grounds for diseases like cholera, a common killer in the United States in the 18th and 19th centuries.
Diseases like smallpox ravaged the Continental Army. George Washington ordered soldiers at Valley Forge to take part in an early form of vaccination, which built immunity and possibly saved the army from being decimated.
A man uses an inhalation device in the late 1890s, around the time period public health professionals began to recognize diseases like tuberculosis as a major public health threat.
When we talk about big achievements like clean air, clean water, vaccines, motorcycle helmets, seat belts, it often feels distant from people’s actual interactions with the public health system.
Public health is not the same as healthcare—a distinction that matters. Healthcare is what happens when an individual gets sick. Public health is everything we do, collectively, to keep people from getting sick. Healthcare treats a patient. In public health, the community is the patient.
“Some people may not be familiar with the various elements of public health,” said Brandon Talley, PhD, MPH, who leads enterprise strategy at the CDC Foundation. “When we talk about big achievements like clean air, clean water, vaccines, motorcycle helmets, seat belts, it often feels distant from people’s actual interactions with the public health system.”
That distance is by design, but it should not be silent: public health works best when it disappears into the background of life—when the cholera outbreak does not happen, when the mother survives delivery, when the child grows up to be old.
The Rise of Public Health
The arc of public health in the United States, compressed, looks like this. For the country’s first century, public health was sanitation by intuition: cities built sewers and organized local health boards before anyone fully understood why disease spread. Boston’s Board of Health was founded in 1799, with Paul Revere as its first president. Then came the germ theory of disease, which Dr. Curran calls the most transformative shift in the field’s history.
“It legitimized and helped us understand the infectious nature of all of these illnesses,” Dr. Curran said. The cascade that followed—vaccines, antibiotics, food safety requirements, the founding of CDC in 1946, the polio vaccine in 1955, smallpox’s eradication in 1980—reshaped what an American life looks like.
CDC named 10 great public health achievements of the 20th century, and the list reads like a quiet inventory of how American life changed. Among them are motor vehicle safety, safer workplaces, control of infectious diseases, vaccination, the steep decline in heart disease and stroke deaths, safer foods, healthier mothers and babies and the recognition of tobacco as a killer. Together, these and other achievements added roughly 25 years to the average American life over a single century. But the increase over the nation’s history is even more astounding. In that 250-year history, life expectancy has increased from just 35 years in 1776 to 79 years today.
Another critical advance in protection and prevention is the evolution of public health monitoring, which allows health professionals to quickly identify emerging health threats, inform responses and assess the impact of interventions. While 19th and early 20th century approaches relied on reports generated by individual physicians and submitted to local health authorities, limiting the speed and reach of public health responses, today’s formal disease reporting system allows for standardized case definitions to improve accuracy, coordinated information sharing and improved lab testing for faster and more accurate disease diagnosis.
James Curran, MD, MPH, former professor of epidemiology and dean of the Rollins School of Public Health at Emory University. Dr. Curran led the task force on HIV/AIDS at the Centers for Disease Control and Prevention.
A school doctor giving exams to students in the 1950s. The control of infectious diseases was named by CDC as one of the 10 greatest public health achievements of the 20th century.
Brandon Talley, PhD, MPH, executive vice president, chief impact and innovation officer, leads enterprise strategy at the CDC Foundation.
These evolutions have impacted every corner of public health, helping health officials collect, analyze and interpret health data so they can identify health threats and take action to protect communities. But there is so much more that is needed today, particularly when you compare healthcare—and the electronic health care achievements—to the disparate and still slow public health data collection approaches.
“Good surveillance is the guidepost and conscience of public health,” Dr. Curran said. Experts agree, though, that much more investment is needed to ensure public health systems can continue to build on the progress of the past 250 years in the next 25 years.
Looking Ahead
The next chapter, Talley suggests, will be defined less by lifespan than by health span—how many of those added years are lived well.
“The distance between lifespan and health span is growing,” Talley said. “Bringing those two things closer together is one of the key challenges of the next 25 years.”
Accomplishing that goal, Talley said, means both looking at public health holistically and refreshing our approach to building and maintaining a strong public health system.
“Public health has always been built through a mix of capabilities that no single sector holds,” Talley said. “What comes next will depend on how effectively those capabilities—public, private and philanthropic—are brought together into a functioning system.”
Over the coming months, this series will spend time inside specific chapters of our country’s 250-year public health story. Each of them will provide partial answers to fundamental questions Americans have been asking, in one form or another, since 1776: how can we improve our health, and how can we improve the health of our communities?
While challenges will always arise, public health, at its best, has borne out that while threats keep coming, the country can rise to meet them.
Check back here for the next story in our 250th anniversary series, detailing the 1869 establishment of the country’s first public health department, and what the CDC Foundation is doing today to strengthen public health departments across the United States.
