Public health may be conceptualized as
- Analyzing the health of a population and the threats it faces is the
basis for public health.
- Science of protecting the safety and improving the health of
communities through education, policy making and research for
disease and injury prevention.
Comprehensive definition of Public health (Charles-Edward Amory
Winslow, 1920 ):
“The science and art of preventing disease, prolonging life, and
promoting health and efficiency through organized community
- 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
- The development of the social machinery to ensure everyone a
standard of living adequate for maintenance of health
So, organizing these benefits as to enable every citizen to realize his
birth right of health and longevity.
Public Health Specialist and Clinician
In the medical field, clinicians treat diseases and injuries of one
patient at a time. But in public health, we prevent disease and injury.
Public health researchers, practitioners and educators work with
communities and populations. We identify the causes of disease and
disability, and we implement large scale solutions.
For example, instead of treating a gunshot wound, we work to
identify the causes of gun violence and develop interventions.
Instead of treating premature or low birth-weight babies, we
investigate the factors at work and we develop programs to keep
Instead of prescribing medication for high blood pressure, we
examine the links among obesity, diabetes and heart disease—and
we use our data to influence policy aimed at reducing all
In public health, microbiologists work to find a vaccine for malaria,
while behavioral scientists research ways to discourage populations
from smoking. Environmental health scientists work to discover
which foods prevent cancer, while health policy analysts evaluate
health insurance programs and make recommendations. And
epidemiologists identify trends in health and illness, looking for
links, causes and interventions in areas such as HIV/AIDS,
tuberculosis and infant mortality.
Public Health Health Care
Population focus Individual patient focus
Public health ethic Personal service ethic
Prevention or public
Diagnosis and treatment
and field involvement
and patient involvement
Clinical sciences peripheral to
Clinical sciences essential to
Public sector basis Private sector basis
Components of PH
Public health is an interdisciplinary field. It includes:
- Management of health services
- Environmental health,
- Community health,
- Behavioral health,
- Health economics,
- Public policy,
- Mental health,
- Occupational safety,
- Gender issues in health, and
- Sexual and reproductive health.
Rehabilitation is “the combined and coordinated use of medical,
social, educational, and vocational measures for training and
retraining the individual to the highest possible level of functional
Salutogenesis is a medical approach focusing on factors that support
human health and well-being, rather than on factors that cause
Public Health Activities
• Prevents epidemics
• Protects the environment, workplaces, housing, food, and water
• Monitors health status of population
• Mobilizes community action
• Responds to disasters
• Assures quality, accessibility, and accountability of medical care
• Reaches out to link high-risk and hard-to-reach people to needed
• Researches to develop new insights and innovative solutions
• Leads the development of sound health policy and planning
Differentiation among PH, Community Medicine,
Social Medicine & Preventive Medicine
GREAT deal of confusion exists with regard to the meaning of the
terms "public health," "community medicine," "social medicine," and
"preventive medicine." The terms are often used interchangeably, a
practice which adds to the confusion.
Two basic concepts are at issue: public health on the one hand, and
community/social/preventive medicine on the other. The latter three
terms have different historical roots, but reflect a more or less
The key word: community, social and preventive medicine are
considered to be, a subdivision of the overall discipline. The common
denominator of all three of these terms is "medicine." Indeed, they
constitute a very minor subdivision of medicine.
The concept of public health, on the other hand, is that of a major
governmental and social activity, multidisciplinary in nature, and
extending into almost all aspects of society. Here the key word is
"health," not "medicine“.
The term "preventive medicine" stems in USA from a period when
public health was almost exclusively concerned with the prevention
of infectious diseases either by preventing the occurrence of a
disease or by halting a disease and averting resulting complications
after its onset and was dominated by the medical profession.
"Social medicine" is a product of France, Germany, Belgium and
other European countries. Firmly based in the medical profession, it
reflected a concern with the role of social factors in the etiology of
disease, and the need for government action in the areas of disease
prevention and medical care.
Rise of Public Health:
The Nineteenth Century: The Great Sanitary Awakening
In the era of unplanned industrialization
in nineteenth century, "The great
sanitary awakening"—the identification
of filth as both a cause of disease and a
vehicle of transmission, and the ensuing
embrace of cleanliness—was a central
component of nineteenth-century social
reforms and advancement in public
- Illness came to be seen as an indicator of poor social and
environmental conditions, as well as poor moral and spiritual
- Cleanliness was embraced as a path both to physical and moral
- Disease control shifted from reacting to intermittent outbreaks to
continuing measures for prevention.
- With sanitation, public health became a societal goal and protecting
health became a public activity.
The Development of Public Activities in Health
- Edwin Chadwick, a London lawyer (1838), is one of the most
recognized names in the sanitary reform movement.
- Under Chadwick's authority, a commission conducted studies of the
life and health of the London working class in 1838 and that of the
entire country in 1842.
- The report of these studies, ‘General Report on the Sanitary
Conditions’, was a document of the appalling conditions in which
masses of the working people were compelled to live, and die, in the
industrial towns and rural areas of UK.
- Chadwick documented that the average age at death for the gentry
was 36 years; for the tradesmen, 22 years; and for the laborers, only
- To remedy the situation, Chadwick proposed what came to be
known as the "sanitary idea."
- His remedy was based on the assumption that diseases are caused
by foul air from the decomposition of waste.
To remove disease, therefore, it was necessary to build a drainage
network to remove sewage and waste.
- Further, Chadwick proposed that a national board of health, local
boards in each district, and district medical officers be appointed to
accomplish this goal.
- Chadwick's report eventually was adopted in the Public Health Act,
of 1848 in UK, and subsequently American Public Health Act 1872,
which both promoted sanitation and engineering as means of
Beneficence refers to actions or rules aimed at benefiting others.
The concept of non-maleficence is embodied by the phrase, "first,
do no harm," or the Latin, ‘primum non nocere’. “Non-Maleficence”
requires an intention to avoid needless harm or injury that can arise
through acts of commission or omission. In common language, it can
be considered “negligence” if you impose a careless or unreasonable
risk of harm upon another.
The principle of autonomy, views the rights of an individual to self-
determination. This is rooted in society's respect for individuals'
ability to make informed decisions about personal matters with
Social justice is a concept of fair and just relations between the
individual and society. Social justice assigns rights and duties in the
institutions of society, which enables people to receive the basic
benefits and cooperation.
Truth-telling, or veracity, can be defined as the avoidance of lying,
deception, misrepresentation, and non-disclosure in interactions
with patients or relevant to patient care.
Surveillance is the continuous, systematic collection, analysis and interpretation of health-
related data needed for the planning, implementation, and evaluation of public health
Cholera, a fatal intestinal
disease, was rampant
during the early 1800s in
London, causing death to
tens of thousands of
people in the area. Cholera
was commonly thought to
be caused by bad air from
rotting organic matter.
Cholera — A Public Health Approach
John Snow is best known for his
work tracing the source of the
cholera outbreak and is
considered the father of modern
John Snow, Physician
Cluster of Cholera Cases around ‘Broad Street Pump’ Site Locations
Risk Factor Identification — What Is the Cause?
Intervention Evaluation — What Works?
Through continuous research, Snow understood what
interventions were required to
• stop exposure to the entire supply of
contaminated water in the area
Implementation — How Do You Do It?
John Snow’s research
convinced the British
government that the source of
cholera was water
contaminated with sewage.
Thus Broad Street Pump to
supply water was sealed for
Three Core Functions of Public Health
Systematically collect, analyze, and
make available information on
population at risk to identify health
problems and priorities.
Promote the use of a scientific
knowledge base in policy and
decision making to solve
Ensure provision of services to
those in need
Ten Essential Public Health Services
1. Monitor Health
2. Diagnose and Investigate
3. Inform, Educate, Empower
4. Mobilize Community Partnership
5. Develop Policies
6. Enforce Laws
7. Provide Care
8. Assure a Competent Workforce
Core Functions at Government Levels
Report on local
smoking in public
Resources to help
Partners in the Public Health System
Ensuring the Conditions
for Population Health
Other Partners in Public Health
• Vehicle for public discourse
• Health education and promotion
• Health communication
• Social media as catalyst
• Employer-sponsored health insurance
• Wellness initiatives and benefits
• Healthy workplaces and communities
• City planning
• Health in all policies
• Public Service
Other major global health issues now at the forefront include:
- Infant mortality
- Water scarcity
- Environmental risk factors (factory emissions, car exhaust, tobacco
- Tobacco use
- Global warming
- Substance abuse
Ethical issues and challenges of Public Health
1. Political conservatism : Reluctant to any change in health policy.
2. Individualism – Individualistic societies resist the notion of public
health’s concern for the collective.
3. Economic impacts - Public Health regulations affects the industries
(E.g. tobacco), those paying for the public health benefits may not
necessarily be the beneficiaries (E.g. Regulatory actions for worker
safety raising costs to consumers).
4. Preference for immediate result: People may not be willing to pay
costs for benefits that would accrue in the long future (E.g. measures
to limit global warming) and it is easier to calculate current costs
incurred for public health than the benefits that would come later.
5. Promoting public welfare versus individual liberty – Extent to
which governments should restrict individual freedom for the
purpose of improving community health.
6. Libertarianism – Restrictions on individual behavior for protecting
their own health (E.g. enforcing seat belts). libertarianism claims
that “the only purpose for which power can be rightfully exercised
over any member of a civilized community ,against her / his will is if
her/his act harms others( E.g. regulate drunk behavior no drinking)
7. Public health measures and religion/moral – Some public health
measures are not acceptable on religious and moral grounds ,(E.g.
sex education and distribution of contraceptives and/or condoms to
8. Values and responsibilities - Health authorities deciding on values
and choices of those they serve (e.g. whether some one should not
take the responsibility on behavior causing ill health such as
smokers, alcoholics, promiscuous people).
9. Surveillance versus cure – Surveillance is costly and time taking;
where as, cure is immediate benefit.
10. Dilemmas in Cost Benefit Analysis – Difficulty of valuing life, and
values to be assigned for the rich versus the poor.