Meeting the Public Health Challenges of a New Era:
Report of the University of Michigan
School of Public Health Review Committee
March 17, 1994

The Field of Public Health

Definition of the field

Public health has many faces. It includes such seemingly diverse activities as scientific investigation of the causes of disease, collection and analysis of vital statistics, immunization against communicable disease, protection against hazards in the workplace, environmental sanitation, educational campaigns to encourage health-promoting behaviors, development of health policy, and organization of health care delivery and financing. Yet imbedded within this diversity is a coherence of purpose and function. In this and succeeding subsections, we examine the unifying and identifying dimensions of public health.

Public health can be defined, loosely, as the set of activities a society undertakes to monitor and improve the health of its collective membership. The critical components of this definition include one that is explicit and one that is implicit. The explicit element is the emphasis on the health of the collective society, rather than that of the individuals who form it. Although in one sense the former is simply the sum of the latter, approaches to improving the health of population groups differ from those that focus on the health of individual citizens. This relates to the implicit component of the definition: because maximal gains in the public's health can be attained by avoiding disease in the first instance, public health concentrates on disease prevention and health promotion, rather than on the treatment of existing illness.

Focusing on disease prevention and health promotion in the context of the entire population accords public health a unique position in the constellation of professions devoted to improving the health of humankind. Although all of the other health professions--medicine, dentistry, nursing, pharmacy, allied health--are somewhat concerned with preventing disease, none but public health has this objective as its main focus. Similarly, none but public health has the whole community as its target. Outside the realm of public health, professional endeavors are dominated by one-on-one clinical interventions, with individual practitioners dedicated to addressing the health needs of individual patients. Typically, medical and other clinical professionals devote much of their work to trying to repair the damage that unhealthy lifestyles and environments inflict. In contrast, public health aims to understand the basic causes of such diseases and then works to foster social and environmental conditions in which people can avoid diseases in the first place.

The two defining elements of public health also account, in large part, for the fact that among all these professions, public health is likely the least understood. By virtue of its emphases on population health rather than the health of the individual, and on disease prevention rather than palliation or cure, public health lacks a large and dedicated political constituency among the general public. It also has the unfortunate characteristic of being nearly invisible precisely when it is most successful: public health measures its achievements in terms of future illnesses avoided, disabilities prevented, and premature deaths that do not occur, each of which goes largely unappreciated by its beneficiaries.

In contrast to the invisibility of the benefits of public health, the activities of public health are observable and, in varying degrees, considered costly (e.g., the regulatory apparatus assuring safety and sanitation), of uncertain value (e.g., media health education campaigns), and even occasionally painful (e.g., immunizations). Furthermore, public health activities--public health costs--occur in the present, while the (less visible) benefits accrue in the more distant future.

The combination of visible, contemporary costs and invisible, distant benefits is not a formula for public adulation, much less support. Disease prevention, however, does happen to be the formula for contributing the most to the health of the public, at a cost well below that associated with attempts to remedy and cure existing illnesses. Building on work by the Centers for Disease Control in the late 1970s, both the Institute of Medicine and the Public Health Service have recently concluded that only a tenth of premature deaths in the United States could be avoided by improvements in access to medical treatment, while changes in health behaviors could avoid fully half, with environmental improvements yielding another 20 percent. (The balance, 20 percent, is associated with inherited conditions only bow being fully researched.) Although this analysis does not reflect the complex interactions among these factors, it emphasizes the potential contribution of public health interventions. Yet despite this potential, spending on public health constitutes a minuscule fraction of that devoted to disease treatment. The Public Health Service estimates that less than 1 percent of total health expenditures are devoted to population-based public health functions and, further, that all expenditures on disease prevention combined are less than 5 percent of the sum the nation devotes to personal health care.

Mission and functions

In 1988, the Institute of Medicine Committee for the Study of the Future of Public Health defined the mission of public health as "fulfilling society's interest in assuring conditions in which people can be healthy. Its aim is to generate organized community effort to address the public interest in health by applying scientific and technical knowledge to prevent disease and promote health."

To achieve this mission, it identified three core functions for public health: (1) assessment of the health of the population, through collection of data, statistical and epidemiologic analysis, and dissemination of findings; (2) development of comprehensive public health policies deriving from a scientific knowledge base and an appreciation of the political process; and (3) assurance of the availability of needed services to achieve agreed health goals for the community, by encouraging appropriate actions by other entities (public or private) requiring such actions through regulation, or directly providing services. Last year, a separate body (the Council of Linkages between Academia and Public Health Practice) suggested a list of 10 organizational practices that comprise the specific functions grouped in these three core areas.

In its seminal 1979 publication, Healthy People, the Centers for Disease Control grouped the determinants of premature mortality and avoidable morbidity into the four categories cited above: health behaviors ("lifestyle"), the environment, human biology, and health services. While there are important interactions among these categories, and indeed often blurred lines between them, these four areas reflect the central substantive "venues" in which the functions of public health are carried out. Thus, structurally, public health can be described by the two dimensions of (1) core functions and (2) these principal determinants of human health, themselves subject to a myriad of important social, technological, and institutional forces.

Challenges and opportunities

Through the past century and a half, two factors have characterized the emergence of modern public health: the development of a base of scientific knowledge about the genesis and control of disease, and the growth of the public's acceptance of the possibility and, ultimately, desirability of disease control. This was as true in the latter half of the 19th century, when modern principles of sanitation were first employed to disrupt communicable, disease transmission in overcrowded cities, as it is today, when researchers; health educators, and government officials employ the full arsenal of public health weapons to combat chronic disease.

The achievements of public health are remarkable. In developed countries such as the United States, life expectancies have soared during this century, approaching what some scientists believe to be a "natural limit." (In the United States, life expectancy has increased by two-thirds, from 47 years at the turn of the century to 76 years at present.) Infant mortality has fallen by more than an order of magnitude, from at least 100 per 1000 live births to fewer than 10. With notable exceptions, such as HIV/AIDS, previously fatal infectious diseases have been transformed from the principal source of death in such societies to a relatively infrequent and typically benign source of illness.

Although medical interventions account for a portion of this achievement, analysis has established conclusively that most of it is directly attributable to such time-honored public health activities as environmental sanitation and health education. For example, although many have credited the development of streptomycin and later BCG vaccination with taming the plague of tuberculosis in the U.S. and Europe, the most substantial decline in TB deaths considerably predated the introduction of these drugs. The decline resulted from changes in contact and disease transmission patterns between infected persons and the healthy population. Similarly, improved emergency medical services and new medical technologies have contributed to recent dramatic decreases in age-adjusted heart disease and especially stroke mortality. However, the lion's share of these declines is due to effective public health interventions to control blood pressure, reduce cigarette smoking, increase exercise, and improve diet.

While health professionals welcome the recent successes in the area of cardiovascular mortality, the fact remains that, in the developed countries, with the infectious diseases much less of a threat, the chronic diseases now account for the vast majority of deaths, as well as an enormous burden of morbidity and disability. The product of behavioral choices, genetic predisposition, and a rapidly aging society, chronic disease confronts the public health and medical communities with a uniquely modern challenge, one that accentuates the distinction between clinical curative services and preventive public health interventions. Society can employ health education techniques and provide policy incentives to discourage conditions that produce many of the expensive chronic diseases, or we can continue to invest in their medical management after the fact. The former would seem to be the more rational and certainly less expensive approach, yet the latter appears to be the dominant societal choice, at least to date.

Obviously, we can and should employ both public health and disease treatment approaches in dealing with chronic disease. The issue is the relative mix of the two, and whether they work together or competitively. Herein lies both the excitement and the risk of the contemporary interest in health care reform. Political momentum for a systemic solution to the nation's "health care crisis" has encouraged the Clinton Administration to develop a proposal that at least accords disease prevention modest attention, including both insurance coverage of personal clinical preventive services and a small amount of support for public health infrastructure. Outwardly, public health leaders hail the Administration's recognition of the importance of public health in a serious attempt to reform the health care system. Many perceive this initiative as perhaps the best opportunity within a quarter century to synergistically link the medical care system and the delivery of public health services. Others, however, warily contemplate both current interest in and future action on "health reform" as concerned only with expanding access to medical services and finding cost-containing mechanisms to finance service delivery. They fail to find a genuine commitment to true health reform, which of necessity would emphasize both public and private initiatives in disease prevention and health promotion.

The architects of a few prominent health reform plans, including the Administration's, envision expanding the "turf" of health care delivery organizations to encompass a broader responsibility for community health. Yet no health reform proposal has articulated a vision that creates mechanisms to grapple with violence or a number of interrelated social ills--an epidemic of teenage pregnancy, drug and alcohol abuse, and so on--that reflect our society's failure to adequately address such basic problems as racism, lack of education, and unemployment. The toll of these ills is measured not only in hospital emergency department visits, but also in increasing disparities in poverty rates and in the health status of African Americans and other minorities compared to the majority white population. (During the 1980s, the gap between white and black male life expectancy increased by nearly a fifth.) In all the major domains of concern within public health--lifestyle behaviors, exposure to environmental hazards, and inequities in access to high-quality health care--America's historically disadvantaged populations remain strikingly disadvantaged. The cost is not merely the widening gap in physical health, but also a less tangible and equally important toll on the affected population's sense of dignity, meaning, and purpose in their lives.

The principal reaction to the vastness and complexity of such problems is often resignation and despair. Herein lies what may be the single most important challenge to public health and the other social institutions of our nation: to find ways to diminish these problems, to restore a modicum of health and dignity, even if the fundamental underlying causes of these ills cannot be wholly resolved. Public health has accepted this challenge and is currently working to decrease the amount and sequelae of substance abuse, to understand the determinants of teenage pregnancy, and to reduce racial disparities in health status, to name only a few objectives.

One of the greatest public health challenges of the latter part of this century is the epidemic of HIV/AIDS, which like so many other diseases claims among its victims a disproportionate number of poor and minorities. The disease constitutes a textbook example of the breadth of the art and science of public health. The public health effort includes intensive work to elucidate the causes of the disease and its transmission, from laboratory analysis of the virus to sophisticated computer modeling of the epidemiology of transmission, school- and media-based health education on risk-factor avoidance, and policy development (and politics) to deal with such diverse issues as insurance coverage practices and international immigration policy.

AIDS has reawakened Americans to the fundamental character of public health problems, and to the necessity for public health interventions. In many parts of the world, however, including countries where AIDS takes the greatest toll, a new disease was not needed to remind people about public health basics. Many poor countries continue to suffer illness, disability, and death from diseases that have been virtually eradicated from the industrialized world, or reduced essentially to minor annoyances. Millions of deaths occur each year for want of application of known, uncomplicated, and inexpensive preventive and curative technologies. Malaria is a good example. Two additional prominent examples, mentioned at the outset, are diarrhea and measles, relatively benign illnesses in developed countries, which kill 4 million children under the age of five every year. Clean water supplies, simple vaccinations, and inexpensive treatments such as oral rehydration therapy could virtually eliminate these ancient killers.

Whether at home or abroad, the problems challenging the public heath professions vary from the mundane and familiar, such as measles and malaria, to the novel and complicated, including the emergence of drug-resistant strains of tuberculosis and the growing epidemic of violence. The global population explosion, rapid aging in both developed and developing countries, and widening gaps between minority and majority health demand that public health live up to its unique challenge of integrating social and biological phenomena.

The opportunities for the public health professions range from applying tried and true interventions in areas of evident need, to achieving scientific breakthroughs in the laboratory or, perhaps more importantly, to determining how to grapple with the seemingly inevitable destructive by-products of the cycle of poverty and despair.

Needs

It is easy to say that public health needs more resources. More health personnel, cleaner environments, and a citizenry more cognizant of healthy lifestyles would all reduce illness and premature death. Given the constraints on resources, however, a special need is for leadership. To develop and fulfill the mission of the public health enterprise, the field must attract the best and the brightest at all levels, from entry-level workers to directors of state health departments and presidents of managed care organizations. Thus, public health practice is dependent on its ability to attract intelligent and energetic young people out of college and graduate school. Clearly, this ability will be fostered primarily by the evolution of increasing social respect for and support of public health organizations and endeavors, including the enterprise of higher education in public health.

The Administration's health reform bill explicitly recognizes the importance of public health and proposes resource allocation to back it up. Aided by experts from academia and state and local health agencies, Public Health Service officials are currently developing a detailed agenda of responsibilities for public health organizations and a rationale for their support. Public health leaders have applauded the Administration's recognition of the importance of their field and are lobbying hard to justify and maintain it. They contemplate the future with more than a modicum of concern, however, recognizing that success in clarifying and promoting the public health agenda demands constant vigilance and continuing efforts to explain the benefits and improve the contributions of public health. At the heart of that effort, as one contemplates the future, is the need to cultivate energetic and creative leadership. In this connection, the University of Michigan School of Public Health has a special contribution to make.