What is “public health?”PUBHLTH 200 – Sept. 13, 2011

What does the public think “public health” means?

• Disaster response (e.g., post 9/11)• Health care for the poor• Behavior nannies (e.g., smoke-free laws)• Restaurant inspections for cockroaches, etc.• I dunno (No idea)

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How public health professionals think of public health

• By purpose

• By groups of professionals who practice PH

• By methods most identified with PH: epidemiology and biostatistics

• As governmental health services for the poor

• As the outcome: health of the public Source: Turnock

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CEA Winslow’s 1920 definition

Public health is “...the science and art of preventing disease, prolonging life and promoting health and efficiency through organized community effort for the sanitation of the environment, the control of communicable infections, the education of the individual in personal hygiene, the organization of medical and nursing services for the early diagnosis and preventive treatment of disease, and for the development of the social machinery to insure everyone a standard of living adequate for the maintenance of health, so organizing these benefits as to enable every citizen to realize his [or her] birthright of health and longevity.”

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A more concise definitionDef’n:

Public health is the set of activities a society undertakes to monitor and improve the health of its collective membership.

Distinguishing features:

1.Focus on preventing disease & injury

2. “Patient” is entire community, not individuals

3. “Provider” is society, not individual professionalsSept. 13, 2011 5PUBHLTH 200

How does public health differ from other health professions?

All other health professions (medicine, nursing, dentistry, pharmacy, allied health, social work) typically involve:

• An individual provider• An individual patient• Emphasis on treating illness or disability

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Example of the difference

Example of health care:

Dentist treats dental caries in an individual patient.

Example of public health:

Government fluoridates the water supply, making fluoridated water available to all members of the community. Prevents dental caries.

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Primacy of public health in concept

Public health

Collective health services Individual health services

Medicine Dentistry Nursing Pharmacy

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Hierarchy in practice

Medicine

Other individual health services

Public health

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Why is public health so important? Factors that could avoid premature mortality

• Lifestyle (behavior) 50%

• Environment 20%

• Human biology (genetics) 20%

• Additional medical care 10%Source: Adapted from CDC, 1979; IOM, 1988; and PHS, 1993

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Why is public health so important? Contribution to life expectancy gain

• Of 30-year gain in life expectancy in U.S. during 20th century…– 5 years attributable to medical care system– 25 years from public health improvements in

• Sanitation • Nutrition• Housing • Job safety

Bunker et al., Milbank, 1994

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Relationship between public health (PH) and the medical care system (MC):

Impact on premature mortality

PHMC

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Relationship between PH and MC: Expenditures

MCPH

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Why the PH/MC imbalance?• Market systems (economic interests) cater to

services for individuals; PH is often a public good (or relevant due to externalities)

• Interest group politics; often contentious issues (more on this later)

• What people want (the “Rule of Rescue”)– Current trauma vs. abstract future benefit– Identifiable vs. “statistical” lives

• “Invisibility” of PHSept. 13, 2011 14PUBHLTH 200

Benefits and costs of health promotion programs

Benefits: abstract, deferred

Costs: tangible, immediate

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Benefits and costs of disease promotion

Benefits: tangible, immediate

Costs: abstract, deferred

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Mission of public health“Fulfilling society's interest in assuring conditions in which people can be healthy.”

“[The] aim [of public health] 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.”

Source: IOM, Future of Public Health, 1988

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Core functions of public health

1. Assessment of the health of the population

2. Development of public health policies

3. Assurance of the availability of needed services

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1. Assessment of the public’s health

Requires:

1. Data collection

2. Statistical and epidemiologic analysis

3. Dissemination of findings

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2. Development of public health policies

Requires:

1. Use of a scientific knowledge base

2. Appreciation and use of the political process

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3. Assurance of the availability of needed services

Relies on:

1. Encouraging appropriate actions by other entities (public or private)

2. Requiring such actions through law or regulation

3. Directly providing services

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10 essential public health services1. Monitor health status to identify community health

problems

2. Diagnose and investigate health problems and health hazards in the community

3. Inform, educate, and empower people about health issues

4. Mobilize community partnerships to identify and solve health problems

5. Develop policies and plans that support individual and community health efforts

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10 essential public health services6. Enforce laws and regulations that protect health

and ensure safety7. Link people with needed personal health services

and assure the provision of health care when otherwise unavailable

8. Ensure a competent public health and personal health care workforce

9. Evaluate effectiveness, accessibility, and quality of personal and population-based health services

10. Research for new insights and innovative solutions to health problems

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Five core areas of public health

• Epidemiology

• Biostatistics

• Environmental Health Sciences

• Health Behavior & Health Education

• Health Management & Policy

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Epidemiology

Concerned with analyzing and describing patterns of occurrence and determinants of diseases in human populations.

Epidemiology is the core science of the field of public health.

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Biostatistics

Focuses on the development and application of statistical and mathematical methods to the design and analysis of public health problems and biomedical research.

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Environmental Health Sciences

Aims to protect human health from adverse environmental conditions -- in particular from harmful practices and harmful exposures in air, water, and food in the workplace, home, and ambient environment.

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Health Behavior & Health Education

Addresses the factors associated with health-related behavior and health status, and develops and evaluates educational activities designed to improve individual and community health and quality of life.

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Health Management & Policy

Focuses on improving access to, financing of, and delivery of high quality health services, and on developing and implementing cost-effective public health policies

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Definition of disease prevention

[A]nticipatory action taken to reduce the possibility of an event or condition occurring or developing, or to minimize the damage that may result from the event or condition if it does occur.

Source: Pickett and Hanlon, 1990

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Levels of Prevention and Effects

Prevention Primary Secondary Tertiary

strategy

Disease status Susceptible Asymptomatic Symptomatic

Effects Reduced Reduced Reduced

disease prevalence/ complications/

incidence consequence disabilitySource: Turnock, Fig. 3-4

Sept. 13, 2011

Example of prevention levels:Motor vehicle injuries

• Primary– Building divided highways

• Secondary– Requiring safer cars (e.g., airbags) or

driving practices (e.g., wearing seatbelts)

• Tertiary– EMS system

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Example of prevention levels:High blood pressure

• Primary– Dietary education and exercise

• Secondary– BP control medications

• Tertiary– Treatment for disease sequelae

of HBPSept. 13, 2011 33PUBHLTH 200

Agent, host, environment model of disease

Agent

• Traditionally infectious

disease

• A.k.a. EpidemiologicalTriangle Host

Environment

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Epi triangle adapted to nicotine addiction & tobacco control

Agent

Vector

Host

Tobacco products

Tobacco product manufacturers

Smoker/chewer

Incidental host

EnvironmentFamily, friends, culture, media

politics, economics, history

Involuntary smokerAdapted from: Giovino 2002

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Why are public health issues often contentious?

1. Restrictions on individual liberty2. Debate over individual responsibility (“blame

the victim”)

3. Economic interests

4. Morality issues in public health measures

5. Politics in science

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1. Restrictions on individual liberty

• Why are they imposed?

– “Tragedy of the commons”: Must restrict individuals’ freedoms to protect the greater good of the entire community (e.g., think pollution control).

• “Public goods”; “externalities”

– Paternalism (e.g., seat belt laws)

– Social norms, morals (e.g., sodomy laws)

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1. Restrictions on individual liberty (cont’d.)

• Behavior that directly affects others (examples)

– Prohibitions against criminal activity (murder; abuse; theft)

– Speed limits; traffic lights; etc.– Prohibiting drunk driving– Banning smoking in public places– Quarantining people with infectious disease– Requiring immunizations for school enrollment– Prohibiting various forms of pollution

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1. Restrictions on individual liberty(cont’d.)

• Behavior that indirectly affects others (examples)

– Motorcycle helmet and seat belt laws– Bans on illicit drugs

– Sodomy laws– Abortion laws– UM campus-wide smoke-free policy (outdoors as well

as indoors)

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2. Debate over individual responsibility (“blame the victim”)

Question: Are people suffering from problem X at fault for the problem – and therefore individually responsible for resolving it – or are they victims who need and deserve (public) assistance?

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2. Debate over individual responsibility (“blame the victim”) (cont’d.)

Examples:– Smoking– Obesity – HIV/AIDS– Drug/alcohol addiction– Homeless (including result of recent spate of foreclosures)

– Poverty

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3. Economic interests

• Often powerful economic interests hurt by public health regulations (e.g., tobacco, alcohol, food companies; polluting firms; health care insurers, hospitals, providers; local retailers such as restaurants and bars)

– Powerful economic interest = political lobby

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3. Economic interests (cont’d.)

• Cost burden falls on different people than does benefit derived

– Benefit often to the poor and politically disenfranchised– Cost often from wealthy and politically connected

• Politics of current costs for future (abstract) benefits– Political interests– Budget balancing– Politicians’ discount rate

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4. Morality issues in public health measures

• Intensely felt positions deriving from sense of moral or religious right or norms

– Abortion– Sex ed– HIV/AIDS prevention (safe sex, clean needles)

– Gay marriage– Stem cell research

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5. Politics in science• Administrations often promote their social/

political agendas by interfering with science– Withholding research resources (e.g., early AIDS)

– Tying resources to compliance with policy positions (e.g., no support through USAID to programs promoting birth control)

– “Litmus tests” for high-level appointees– “Stacking” review bodies with “partisans” (e.g.,

corporate consultants)

– Misrepresenting or suppressing scientific findings (e.g., global warming)

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What is public health?

• Under-appreciated (“invisible”), under-funded, under-practiced

• Difficult

• Politically challenging

• Requires expert mix of science and politics

• Last but not least: PH is importantSept. 13, 2011 47PUBHLTH 200

Thursday: History of public health

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