Introduction to Public Health

Introduction to Public Health

[MUSIC PLAYING] [MUSIC PLAYING] Welcome to an introduction
to public health. My name is Susie McCarthy. As a health education
specialist at the CDC, I’ve worked in a variety
of areas of public health, including children’s
health, infectious diseases, chronic diseases, and most
recently public health workforce development. Public health is a dynamic
and multi-disciplinary field as you’ll see from this
introductory course. This slide shows the
outline for the course. We will begin by discussing
the purpose of public health and a few key terms. We will then look at some events
in history of public health. Next, we’ll go through
the public health approach and apply it to a
public health problem. We will then cover
the main functions and essential services
of public health to show the broader context and
identify different groups who have a stake in public health. Lastly, we’ll discuss factors
that determine health, and I’ll present the
health impact pyramid as a framework for
influencing public health at different levels. This introductory
course should enable you to achieve the
learning objectives on the slide which align
with the course outline that I just covered. So what is public health? CEA Winslow was a leading
figure in the development of the modern study
of public health. Read this definition
of public health that he developed
almost a century ago and consider key
words or phrases in the definition
that speak to you or tell you what
public health is. You might notice that as a
combination of science and art, public health offers many
opportunities to be creative. Public health is not only
about preventing and treating disease, but it’s also
about promoting good health. Winslow says this is done
through organized efforts. So what are some examples
of organized efforts? You might think about how
national surveillance systems are set up, how our waste
management infrastructure is built, or how the latest
vaccination recommendations are developed and communicated. From Winslow’s
definition, you might note that public health gives
people and organizations information to help
them make choices that inform them and help
them improve their health or the health of others. Public health also occurs
at different levels. Individual, organizational,
and community levels, and even more broadly
at the city-state, national, and
international levels. So here are two statements about
the mission of public health. The Institute of
Medicine says that there is a societal interest
in ensuring conditions in which people can
be healthy, and we’ll come back to the concept of
assurance later in the course. The World Health
Organization, or WHO, says public health is about
serving the greater good. The maximum benefit for the
largest number of people. From these two
statements, you can see that public health
focuses on groups of people rather than only on individuals. And at the core
of public health, there is this principle
of social justice. That people have the
right to be healthy and to live in conditions
which support their health. So now that we know
what public health is, let’s review some
common key terms. Clinical care is the prevention,
treatment, and management of illness, and the preservation
of mental and physical well being through health services. This is all also more commonly
referred to as medical care or health care. A determinant, also known
as a health determinant, is a factor that contributes
to the generation of a trait, such as one’s ethnicity
or genetic makeup. But more broadly, the
context of people’s lives determines their
health, and we’ll go into more detail about
health determinants also later in the course. Epidemic or outbreak, as
you can see on the slide, is the occurrence in a
community or region of cases of an illness or a specific
health related behavior in excess of what
you would normally expect to see in that area. An epidemic and outbreak
are used interchangeably. However, epidemic usually
refers to a larger geographic distribution of illnesses
or health related events. It’s basically an epidemic
occurs when a disease spreads rapidly to many people. You might also hear
the term pandemic, which is kind of an
epidemic on steroids. It often has a
global impact, which means people on
multiple continents are affected by it, often
crossing borders and going into different countries. A health outcome is the result
of a medical condition that directly affects a person’s
life in terms of its quality or length. And think about the health
outcomes for somebody who’s living with HIV, for
example, or who has diabetes. All right. So now we’ve come to
a knowledge check, and I ask you to fill in the
blank with the correct answer. Does public health
aim to provide groups of people or
individuals with the right to be healthy and
live in conditions that support their health? The answer is groups of people. Public health focuses on
populations rather than individuals. The next knowledge
check is asking, what is a disease occurrence
among a population that is in excess of what’s expected
for a given time and place? Is it pandemic, intervention,
epidemic or outbreak, or prevention? And the correct answer
is epidemic or outbreak. Now we’ll take a look at a
few historical highlights of public health
through the four lenses of sanitation and environmental
health, pandemics, disaster response and
preparedness, and prevention through policy. So the first lens will
look through encompasses the control of
disease and promotion of health through sanitation to
ensure a healthy environment. Here are three examples
from around the globe of how public health
has been implemented to contain infectious disease
through environmental measures. So around 500 BCE, it’s
recorded that the ancient Greeks and Romans actively practiced
sanitation measures. Fast forward approximately
two millennia and we see the work
begun long ago in Greece continuing in the United
Kingdom through the passage of the Public
Health Act of 1848, which established a
central board of health and placed responsibilities
for sanitation in the hands of burroughs. In 1970 in the United
States, the administration of President Nixon established
the Environmental Protection Agency, which still
today protects our health by safeguarding
air, water, and land. So next we’ll explore
pandemics, and you’ll recall that these are similar
to epidemics except that they affect even larger populations,
often across countries and continents. So influenza, or the flu, has
caused pandemics many times during both the distant
past and in recent history. Almost a century
ago, the Spanish flu infected 500 million
people across the world, including in remote Pacific
Islands and the Arctic. And it’s estimated that it
killed between 20 and 50 million people. More recently, the
influenza pandemic in 2009 infected people
in 214 countries, causing almost 19,000
confirmed deaths. And while 19,000
confirmed deaths is still many deaths too many,
it’s nowhere near the type of fatality rate that
we saw 100 years or so ago when the Spanish
flu ran rampant. So we have made tremendous
strides in public health in terms of
controlling influenza, but preparing for
and controlling the effects of influenza will
likely remain top priorities for public health. Historically, polio was a
common and highly feared disease that caused
severe illness, including paralysis and even death. Thousands of people lined up
to receive the polio vaccine after it was introduced in 1955. An initiative to
eradicate polio was launched in 1988
because of outbreaks in more than 125 countries. And because of those
efforts, at this time, polio exists in only
a few countries. Lastly, with our last
example, during the 1980s, human immunodeficiency
virus, or HIV, emerged and spread
rapidly across the globe. Public health has
responded to this pandemic by developing new ways
to diagnose and treat those who are infected. New infections of HIV are down
20% over the past 10 years, and that’s a sign
that the public health interventions are successful. So the third area we’ll
explore is public health’s role in preparedness and
disaster response, both for natural disasters
and human made threats. The use the biological warfare
to infect people and animals goes back centuries. One of the earliest
accounts is the use of plague as a weapon of war
during the Siege of Caffa in the 14th century AD. And Caffa is now an area
where modern day Ukraine is. So back then,
attacking Tartar forces likely catapulted
dead bodies filled with the infection of plague
into the city of their enemy. This contributed to the
spread of the Black Death in that area. During disease
outbreaks that could be related to
bioterrorism today, the public health community
is prepared to distribute lifesaving pharmaceuticals in
antidotes, medical supplies, and equipment to locations
across the country and even the world. In the wake of the terrorist
attacks in the United States on September 11, 2001,
which I’m sure all of you remember, public
health workers were on the ground at the World
Trade Center and at the Pentagon to conduct surveillance to
identify outbreaks of disease and health conditions that might
have resulted from the attacks. Public health workers
monitored occupational health of first responders
and city residents as well as
environmental conditions to detect health threats in
the aftermath of the attacks. Public health also response
to natural disasters. After Hurricane
Katrina hit in 2005, public health workers joined
disaster relief agencies to provide emergency
services and dispatched teams to conduct surveillance
for illness and injury among residents in their
homes and those who had been relocated to shelters. So the last lens
we’ll look through as we view public health
history is health policy as a means of prevention. We implement a range of policies
across areas of public health to support efforts
on a societal level. So as far back as 1500 BCE,
Leviticus, the third book of the Hebrew Bible, is believed
to be the first written health code in the world. The book addresses personal
and community responsibilities and includes guidance
about bodily cleanliness, sexual health behaviors, and
protection against contagious diseases, including
the isolation of people with leprosy. You might recall hearing
about leper colonies back then in history. So in recent decades, we’ve
had tremendous movement in tobacco legislation. Laws banning smoking in
the workplace, restaurants, and other public
places have been passed to encourage
smokers to quit while also protecting
nonsmokers from the effects of secondhand smoke. Also, increases
in cigarette taxes have been shown to be
a deterrent for buying cigarettes. And you’ve probably heard
the term obesity in the news. Approximately 60 million
Americans– nearly one third of all adults– and about one
in five children are obese. And doctors usually
define obesity as a condition in which a
person’s weight is 20% or more above normal weight or
as a body mass index measurement of 30 or more. Policies and laws
related to food labeling, minutes of physical
education and resource for children in
schools, and even access to healthy foods and safe
places to be physically active in communities. These are all examples of
prevention through policy that can impact obesity
in a positive way. So to summarize this
section of the course, we work in public health
to prevent epidemics and the spread of
disease and injuries, protect against
environmental hazards, promote and encourage
healthy behaviors, and respond to
disasters and outbreaks. All right. It’s time for another
knowledge check. Which of the following events
in public health history have been pandemics? And just a hint. There’s more than one answer. Also remember, pandemics are
not the same as epidemics. So the correct
answers are B and C. Both influenza and
polio are examples of pandemic in the
history of public health. So now let’s talk about public
health in the broader context. As we’ve seen, public
health problems are diverse. They include infectious
diseases, chronic diseases, emergencies, injuries,
environmental health problems, as well as a multitude
of other health threats. Regardless of the
topic though, we take the same approach to
a public health problem by following four general steps. First we ask, what
is the problem? In public health, we
identify the problem by using surveillance
systems to survey and monitor health events and behaviors
among a population. And then after we’ve identified
the problem, the next question is, what is the
cause of the problem? For example, are
there risk factors that certain populations
may have that make them more susceptible to disease? Maybe it’s something
in the environment or it’s certain behaviors
that people are practicing. Once we’ve identified the risk
factors related to the problem we ask, well, what intervention
works to address the problem? We look at what’s
worked in the past. Maybe in addressing
the same problem with different
populations we look to see if something might
work with our population, and we look to see if a proposed
intervention would make sense with our affected population. In the last step we ask, how can
we implement the intervention? Given the resources
we have and what we know about the
affected population, will this intervention work? And this is a very
simplified approach. Each of these steps
can be spliced into more specific activities,
but these are really just the general
questions that must be answered to identify a
response to a public health problem. Surveillance, risk factor
identification, intervention evaluation, and implementation. Now to implement the
public health approach, practitioners use and
apply scientific methods that come from a
series of core courses. These sciences include
public health surveillance, which we use to monitor a
public health situation, and epidemiology
enables us to determine where diseases originate,
how or why they move through populations,
how they spread, and how we can prevent them. Public health laboratories
have a very important role in supporting public
health by performing tests to confirm disease diagnoses. And laboratories also
support public health by conducting research
and training that’s valuable to the field. As far as informatics
goes, as we continue to move from the use
of paper documents more to electronic
health records, public health
informatics continues to increase in importance. Informatics deals
with the methods for collecting, compiling, and
presenting health information, and it enables us to use
electronic data effectively when addressing a
public health problem. And lastly, prevention
effectiveness. This is closely linked
to public health policy. Prevention effectiveness
studies provide important economic
information to decision makers to help them compare
interventions and then choose one to implement. So together, these
five core sciences can help us protect and
promote the public’s health by giving public health
practitioners the answers that they need. Public health is
better able to respond to a given situation or
problem by using contributions from each of these sciences. So let’s take a look at
the public health approach and how can it can be applied
to a historical example of an infectious disease. During the 1800s in London,
cholera, an often fatal intestinal disease,
was rampant, causing deaths of thousands
of people within hours sometimes of first symptoms. So at that time, and this was
before bacteria and viruses were recognized as the cause
for many illnesses and diseases, popular opinion
held that cholera was caused by bad air coming
from rotting organic matter. This was known as the
miasma or miasma theory. John Snow, a British
physician during that time, he had a different
opinion of cholera. He believed that the
illness was spreading by way of a contaminated
water supply because sewage was
being routinely dumped into the Thames River and in
cesspools near town wells. Because of his work tracing the
route of the cholera outbreak, Dr. Snow’s often considered the
father of modern epidemiology, and his research changed the
way we look at disease today. So let’s apply the public health
approach to Dr. Snow’s research of cholera outbreak. So this is a slide of a
neighborhood in London, and you’ll recall that
first we need to identify the public health problem. Snow conducted public
health surveillance looking at where those people
with cholera lived in London, and he saw that large
clusters of cases were occurring in
specific areas. So you’ll note the
red circle, and you’ll see more black dots
are in that circle and those represent
cholera cases. So the concentration of
cholera cases, you’ll note, are surrounding
the area of Broad. Street and the black
dots represent the deaths from cholera. Notice the higher density of
deaths around Broad Street. Snow was assisted back
then by a local clergyman by the name of Reverend
Henry Whitehead. He was very, very familiar
with the neighborhood and people who lived there. So together– kind of
working separately but then their efforts combined
together later on– they were able to track down and
interview surviving cholera victims and their families
and geographically map the outbreak. And their efforts
highlight the benefit of linking scientific
inquiry with engagement of community
stakeholders to build the shared ownership of health. So next, Dr. Snow
examined the data and tried to identify
risk factors. So that is he tried to
determine the cause of deaths by using the pattern of
where cases were occurring. So this slide illustrates
the location of the water pumps in the neighborhood. These are the black boxes. So on the basis of
his previous work, Snow believed that water was
a potential source of cholera. So the map reveals that
the larger number of cases occurred in areas
near water pumps, and this observation prompted
Dr. Snow to further research the distribution of
water pumps in London. And he identified where
people who had cholera were drawing their water. His findings showed that
clusters of cholera cases were more commonly located
around certain pumps, particularly the pump on
Broad Street, smack dab in the center of that graph. So through this
research, Dr. Snow concluded that drawing water
from the Broad Street pump was a primary risk factor for
becoming ill with cholera. So after identifying
the likely risk factors, the next step in the
public health approach is to evaluate
potential interventions. With the water supply from the
Broad Street pump identified as the risk factor,
Snow then worked to identify interventions
to address the problem. He did a lot of
continuous research, and from that
research he understood that the interventions required
to control the cholera outbreak were basically two
different interventions. One was to stop exposure
to the contaminated water supply in the neighborhood,
and then on a larger scale, to stop exposure to the entire
supply of contaminated water in the area. So using the final step of
the public health approach, Snow implemented
the intervention by getting the handle removed
from the Broad Street pump. And that prevented people
from drawing their water from that pump
because, again, he believed that the
supply of water was the source of
the contamination. That was a pretty
simple but brilliant way of effectively
stopping their exposure to the contaminated
water supply. And then, after a very long
battle with the politicians and the water
companies in the area, Dr. Snow finally convinced
the British government that water contaminated with
sewage, and not smell or bad air coming from
the waste itself, that it was the water that
was the source of cholera and as well as other diseases. So this resulted in the
implementation of policies and laws for water sanitation,
and that was an intervention on a much larger scale than
just eliminating the threat from any one single water pump. But both interventions
had their importance. All right. It’s time for another
knowledge check. So this knowledge
check just asks you to fill in the blanks
with the correct answers. Each public health
core science helps us to blank and blank
the public’s health by providing public health
practitioners with the answers they need. So I’ll give you a hint. The answers both start with P’s. Public health core sciences
help us protect and promote the public’s health. But if you had anything remotely
close to protect and promote we’ll count that as correct. So with this knowledge check–
this is a matching one. And just match each component
of the public health approach with the
questions that they answer. So again, when we ask
what is the problem, we’re basically talking
about surveillance. When we ask what
is the cause, we’re looking at risk
factor determination. And then we want to know,
well, what’s going to work? What’s going to help to solve
this public health problem? That’s when we’re looking
at intervention evaluations. Possible interventions
that we might be able to implement with
our particular population. And then lastly, by process of
elimination, how do you do it? And that’s where you
basically decide what are you going to implement. So this section of the course
introduces the core functions and essential services
of public health. In 1988, the
Institute of Medicine defined three core functions
of public health agencies that must be carried out
at all levels of government for the overall public health
system to work effectively. The three core functions are
assessment, policy development, and assurance. So assessment is knowing
what needs to be done, and it’s based on the
collection and analysis of data. You have to have data before
you can do anything else. Policy development
is much broader than legislation for one. It can be guidelines, standard
operating procedures, laws, rules, regulations– all
of that is encompassed by policy development. And policy development is
based on the information that comes from the
assessment function, and it provides the
use of such information in policy and decision making. Assurance is making sure that
policies and programs get implemented by providing
public health services to those who need them. So if you’ll briefly reflect
on the mission statement that we discussed earlier of
the Institute of Medicine, that public health is assuring
conditions in which people can be healthy, this is
what this core function is talking about. In this graphic, the
three core functions are on the outside
of the circle. You’ll see assessment
on the top right leads to policy development
underneath and then assurance on the other side. The 10 essential
public health services are grieved underneath
these three core functions. These services are
not a prescription for what public health
agencies should do, but rather they’re
really intended to capture the field
of public health and communicate
what it provides. The strength of a
public health system rests on its capacity
to effectively deliver the 10 essential services
of public health. So using the issue of
tobacco use prevention, let’s explore how the essential
services can be implemented. Under the function
of assessment, what are examples of number one,
monitoring health for tobacco use prevention? So one example is to monitor
health among segments of the population. For example, youth. Another example could be
monitoring global tobacco use prevention by country. For number two, public health
investigates risk factors associated with tobacco use,
such as the risk of developing a certain kind of cancer. Assessing the problem
provides more data to inform policy
development, and that’s the second core function,
you’ll recall, of public health. And that’s, again, on
the outside of the circle at the bottom right side. The third essential
service, which is under policy development, is
to inform, educate, and empower people about health concerns. So think of different
ways that you hear about the danger
of using tobacco. Do you hear it from
your physician? So you see public
service announcements maybe in magazines? So all of those are examples. People must be
informed and educated before they become
empowered to make changes, such as quitting tobacco use
or never starting at all. On a larger scale,
empowerment leads to community mobilization,
which is number four. This might include the
work of advocacy groups to rally support around
banning smoking in restaurants. And that leads to number
five, where policymakers then develop policies to do that
work, to accomplish that work. So what other policies
regarding tobacco use prevention can you think of? Often, people might say,
well, raising tobacco taxes or not selling tobacco products
to people under a certain age. Having a minimum age
requirement and enforcing that in retail establishments. And those are all great
examples of policies. After policies are
enacted, they must be enforced to have an impact. If they’re not enforced,
they don’t do any good. So enforcement is number six
of the essential services of public health. And using our example, this
might be fining someone for smoking on an airplane
because smoking is not permitted on airplanes
per federal legislation. Number seven is to link
people to needed public health services. So an example is to refer
smokers to tobacco quit lines or for counseling so that
they can stop smoking. For number eight,
we need to ensure that a competent public
health workforce is in place to help people quit smoking. And for all of the
interventions we develop, it is critical to evaluate
them for their effectiveness, both during and at their end. And this is number nine. So we ask, did the
anti-smoking campaign do what it was supposed to do? Did the tobacco
cessation program achieve its intended objectives? How successful was the
policy that we implemented to raise taxes on tobacco? Did it deter people
from buying cigarettes and thus, help
people stop smoking? So evaluation is critical
throughout the entire process. The essential services of
enforcing laws, linking to care, assuring a competent
workforce, and evaluation, they fall under that core
function of assurance on the left side of the circle. And you’ll recall
that assurance is ensuring provision of services
to those who need them. Now you’ll note in the middle
of this graph there’s research. So research is in
the middle of all of these core functions
and essential services because it’s continually
informing everything. So think about as new tobacco
products are developed and there are new things
coming out all of the time, CDC’s laboratories
are continuously conducting research
on these new products to help us discover their
potential negative health effects and help us to look
at new products that are being marketed or sold and how we
might combat those and battle the tobacco industry. One important point about
these essential services is that while they’re
shown in a very nice graph and that they occur
in a sequential order, they actually don’t always
occur that way in reality. You might have it
where you are you doing a couple of the
essential services and then you might
skip around or you might skip a couple
of essential services and move to a different one. Sometimes things just
aren’t neatly packaged. Sometimes you might do a few
services and then actually loop back and do them over again. And again, with new
research continually informing everything,
that again prevents a nice chronological,
sequential flow. But if you were to look at
this in a sequential order, it does make sense
that you’d start with monitoring
health and then moving all the way through to insuring
competent workforce to actually carry out whatever the
interventions are that you’ve decided to implement
to achieve better health of the population. So the core functions of
assessment, policy development, and assurance, they
must be carried out at all levels of the government
for the public health system to function effectively. And this slide shows the
core functions at the top and the three different levels
of government at the left. So I’ll just go through
each level of government and give you the example of
assessment, policy development, and assurance. So at the federal level,
an example of assessment would be conducting
national public health surveillance about tobacco. And then a policy, as
we’ve already discussed, is that they’ve banned smoking
on commercial airline flights. And then assurance is that
the federal government, such as CDC, provides
federal grants for anti-smoking
research and tobacco use prevention
cessation and control. At the state level, states
also monitor tobacco use. States have autonomy for
increasing tobacco taxes. If you look across
all states, there are a whole bunch of different
types of tobacco taxes. They’re not all the same amount. That’s completely up to the
states to regulate that. And then lastly, assurance. An example of that
may be a estate that has a proposition, such
as Proposition 99– I believe that was in California–
funding for campaigns to prevent smoking. At a local level,
local communities also report on tobacco use. So that is a way that
they conduct assessment to gather data and diagnose. Then that moves, again,
to policy development. So you have county laws
that prohibit smoking in bars and restaurants. Maybe in your county
those are good things. And then assurance,
at the last level, an example of that
at the local level are resources that county
or a local health department might develop to help
people quit smoking. And they might put
those resources in different languages
that are representative of the populations of people
who live in those communities. So again, very different
levels, but each level has to have a role for all of
these functions and services to work together
and be successful. All right. So this brings us to
a knowledge check. Which of the following is not a
core function of public health? And hopefully you
all got this right. The correct answer is authority. So assurance assessment
and policy development are all functions
of public health. So here’s a second
knowledge check. The essential health
services of monitoring health and diagnosing and
investigating disease relate to which core
public health function? Is it assurance, assessment,
or policy development? And remember, it’s learning
more about the health problem, and so you do that
through assessment. And you have to do that
before you can do anything else in a meaningful way. So the next section
of this course is about the roles
of different groups who have a stake
in public health. The field of public health
requires stakeholders with skills and intervention
programs, policies, research, education, et cetera. Partners include governments,
community groups, clinical care providers, employers and
businesses, the media, academia. I could go on and
on but those are the main groups, at least
that this slide shows, in addition to the
infrastructure provided by the government at all
levels as we just covered. So what other sectors
and fields can you think of that have a
stake in public health? When I talk this over
with other groups, some of the answers
that they provide are transportation, housing,
schools, city planning, law enforcement, faith
based institutions. I mean, all of those
are great examples of just other partners who
have a stake in public health. And some of those are considered
nontraditional partners, but our hope is that they
will become more traditional and people won’t think about
only providing with health care providers, for example. Or that basically, we
realize that there’s a health and all
policies approach, which I’ll get to in a moment. Nongovernmental organizations,
often referred to as NGOs, play a key role
in public health, especially at the
community level. NGOs serve many
different purposes, from advocacy or education
to emergency relief and economic development. [INAUDIBLE] types of NGOs
include professional membership organizations, groups that
focus on a specific health problem, citizen
groups, advocacy groups, and foundations that
support health projects and work at the policy level. So the column at
the right just shows an example of each one of
these types of organizations. Along with public
health, health care plays a vital role in
protecting and promoting the health of people. So while the roles of public
health and health care are complementary,
there are differences that are shown on this slide. Public health, as we’ve
talked about before, focuses on populations
while health care focuses on the
individual patient, which is reflected in
different guiding ethics for both those areas. Public health focuses
on prevention. And while health care is
concerned with prevention to some extent,
its main focus is more on diagnosing and
treating the problem. Each type of laboratory
works jointly, yet public health
interacts with the field on behalf of groups of people. And clinical laboratories work
with health care providers on behalf of
individual patients. And the last row
of the table shows that while clinical sciences
are of peripheral importance to public health, they are
essential to the training of health care providers
on the clinical side. So here are some of the
other primary partners in public health. We’re seeing the role
these days of social media as a vehicle for
public discourse on all matter of issues,
including public health concerns. Whereas historically, it was
more public health agencies and other partners that
have educated the public and promoted healthy behaviors
through news and entertainment media. But now, there is more
of a self promotion as well as social media
continues to take off. Employers and
businesses, obviously. They contribute to
the public’s health by providing health insurance. Workplaces also have
wellness initiatives, such as gym subsidies or
workout facilities on site, and these can promote the
health of their employees. Government agencies,
such as the CDC– they work in partnership with
state, local, and tribal health departments. However, important
contributions are made by other governmental
agencies at all levels. City planning departments can
include sidewalks and bike paths to promote and support
safe places for people to be physically active. Education departments can ensure
healthy food options in schools and in vending machines. Similarly, many other
government agencies work as partners
in public health by including health
considerations in their policy development, and this is known
as a health and all policies approach. There’s just this
concept that regardless of what you do as
you’re planning, think about how can
impact public health. And so that’s what I
referred to earlier. It says health and all policies. And really, that opens up the
opportunity for public health to partner with a
variety– there’s really an endless number of different
types of organizations. And lastly, but not
leastly, academia educates and trains the
public health workforce and conducts research
that informs public health and provides a great
service to the field. So we have another
matching exercise for this knowledge check. You need to match
each stakeholder to its role in public health. So for a vehicle for
public health discourse, the correct answer is media. Newspapers, opinion editorials,
social media, all media. Health in all
policies, as I said, is something that the
government definitely can have an active
role in doing, as well as other organizations. But for the purposes of
this knowledge check, the correct answer
is C, government. Education and training
are things that academia contribute to public health. And the stakeholder that
provides wellness initiatives and employee benefits is
employers and businesses. So the last section
of this course covers determinants
of health and explains how they affect public health. As we discussed
earlier, certain factors determine a person’s
state of health. Scientists typically recognize
the same general categories of health determinants
for any population, and these are genes and
biology, health behaviors, social or societal
characteristics, and health services or medical care. So I would like you to think
of some examples of each of these broad categories. What are some examples
of genes and biology? You might think of a person’s
sex or age or immunity levels. For health behaviors it
could be whether or not a person is a smoker. What are that person’s
eating habits? Whether or not a person
takes medications that are prescribed
for a chronic condition that person has. Social or societal
characteristics. They can include
one’s ability to work, the quality of schools,
where a person lives. What’s the quality of
air, water, and sanitation in that person’s
immediate neighborhood? And then, examples
of medical care are insurance coverage and
even one’s proximity to getting quality health care. This chart is an estimate of
how these four major categories of health determinants influence
health at the population level. The chart shows that
health care is not the major factor
determining our health, yet it represents a substantial
portion of the United States budget. Most of what determines
our health you’ll see at the population level
are the social and societal characteristics, whereas
genes in and biology, they have the least
amount of influence. And then health
behaviors, again, a pretty substantial amount. But it’s really the social
and societal characteristics and the ecology, including
the person’s environment, that has the greatest impact. To address the health
determinants on this slide that we just discussed, we
have to have a plan of attack. A means to effect change. The health impact pyramid
describes such a plan. It shows the impact of
different types of public health interventions. So as we move down the pyramid,
the public health impact grows greater, and as
we move up the pyramid, the amount of individual effort
to achieve impact increases. So let’s start at the top. When we start at
the top and go down, we can provide
counseling and education. We can provide ongoing
direct clinical care. Next, we can provide
clinical interventions that require a more
limited contact but confer long term protection. That’s kind of what
preventive medicine does. We can change the context
to make individuals default decisions be easy decisions but
ones that are the healthiest. And at the bottom
of the pyramid, that addresses the socioeconomic
determinants of health. Interventions focusing on the
lower level of the pyramid tend to be more effective
because they reach broader segments
of society and they require less individual effort. This isn’t to say that what’s
at the top of the pyramid is not important because it is,
but implementing interventions at all levels of
the pyramid, that’s what’s going to achieve
the maximum possible sustained public health benefit. And a point to
emphasize here too is that there are trade offs. We have to sometimes give
up resources in one area in order to have a
larger impact in another. But let’s take a
look at some examples of each level of intervention. So the pyramid
illustrates the impact of different types of
public health interventions. And again, working our way
from the top to the bottom. Counseling and education
in clinical settings, public health
settings– they are regarded by some as the essence
of public health action. I went to school and I actually
majored in health education and promotion when I
got my master’s degree in public health. But being at CDC, I’ve
learned a lot about how all of those other
areas, including the area at the bottom, really
make a substantial impact in interventions. But that’s, again, not–
counseling and education– they’re not as effective
as we would like. But that being said,
there are times when counseling
and education are the only forms of
intervention that are available or appropriate. And when they’re applied
consistently and repeatedly, they can have a positive impact. So moving to clinical
interventions, ongoing medical care for a
health condition is an example. For example, in the case
of cardiovascular disease, these interventions can
have a considerable effect. But we’re also limited
by a lack of access to certain patients who
need that type of care and a lack of adherence
to medical instructions and taking prescriptions as
prescribed in the real world. So again, that medical
care has its limitations. So in the very
middle of the pyramid looking at the intervention
level of preventive medicine, let’s talk about
vaccinations as an example. Vaccinations prevent 2.5
million deaths among children around the world every year. So in this case, a single dose
or instance of an intervention can have a lifelong effect. So this is an example of a long
lasting preventive medicine intervention. The next level
down on the pyramid is where we make
decisions the default by changing the context
in which behaviors occur. And it makes it more difficult
to avoid the intervention. So for example, changing laws
to require seat belt use. Making it easier for
people to wear their seat belts because if you don’t
put your seat belt on, you get this really annoying
beeping noise until you put it on, so you want to put it on
and just make the noise go way. But it’s much easier than it
used to be to wear your seat belt. Banning smoking
in certain public places is another example. Both of these examples
and accomplishments in public health have
had a tremendous impact and saved many,
many, many lives. In another basic example,
some of the buildings at CDC– the newer buildings
for example– when you first walk in, the stairs
are what you see before you see the elevator. And the stairs have
windows and maybe have some plants or some music. So that makes it much more
enjoyable and very easy for people to decide to
take the stairs instead of going all the way around the
corner to find the elevator. So that’s a real basic example
of making the healthy decisions the default. At the base of the pyramid are
the public health interventions that affect
socioeconomic factors. If we can improve
the quality of life by helping people
out of poverty, providing basic sanitation,
improving access to education, helping them get jobs, providing
healthy food, medical care, we can greatly improve
a population’s health. So it’s time for
another knowledge check, and I’d like you to just list
four determinants of health. Now remember, it can be genes
and biology, health behaviors, social societal characteristics,
and health services or medical care. In our last knowledge
check of the course, just fill in the blanks
using the two choices. For number one, as we move
down the health impact pyramid, the public health
impact grows greater. Remember, the base
of the pyramid is the socioeconomic factors. As we move up the
pyramid, the health impact becomes greater in terms of
the amount of individual effort that’s required. Again, all levels of the
pyramid are important, but it’s just a nice
framework for thinking about how interventions
can be implemented at different levels. Within each of the topics
we’ve covered in this course, underlying all of our
actions and decisions is the application of the
public health core sciences. I encourage you to build on this
introduction to public health by learning more about
these core sciences and how they contribute to
the field of public health. Let’s review the learning
objectives for this session. The course provided
content to help you describe the purpose
of public health, define some key terms
used in public health. You’ll recall we talked about
epidemics, health determinants. The course helped you
identify prominent events in the history of public health. That’s where we looked at
a few historical highlights of public health
through sanitation and environmental
health, pandemics, disaster preparedness and
response, and prevention through policy. The course helped you recognize
the core public health functions– those three
functions– and 10 essential services. You should be able
to describe the role of different stakeholders in
the field of public health, as well as to list some of
the determinants of health. And lastly, you
should recognize how individual
determinants of health affect population health. Thank you for your attention
today for the introduction to public health. To receive continuing
education units, CEU credits, for
today’s webinar, please complete the webinar
evaluation on CDC TRAIN by logging in and looking
under My Learning. If you or one of your
colleagues were not able to attend today’s
webinar, an archived version of this webinar will be
available on CDC TRAIN in approximately
two to three weeks. For further information
on CDC webinars, please visit Again, thank you
for participating in today’s webinar. Have a positive and
healthy afternoon. [MUSIC PLAYING]



  • Shimaa Mostafa

    thank you very much,
    it was so interesting lecture

  • Saurav Kumar

    thank you

  • Bello Dalhatu

    I appreciate your lecture

  • Narma Quen


  • Anupama Bishwokarma

    very interesting and helpful lecture

  • hibo cilmi


  • Wessen Kifetew

    Great presentation. Very comprehensive lecture! Thank You!

  • Linda Warren -MDH-

    Great lecture!

  • nuur 143

    is so attractive lecture true

  • Hajara Abdullahi Saulawa

    thanks for sharing your knowledge with us

  • Candia Tom Aliti


  • Abdalla Suge

    thank u for your lecture we hope another

  • Kaafi Ina Caamir Maxamed


  • Kaafi Ina Caamir Maxamed

    my hope

  • Ahmed Aden


  • hauwa ali

    its take care of all endemics n epidemics.

  • Cabdilaahi Dalmar

    important lecture and useful for medical proffessional and undergraduate

  • wilson tolbert

    Thanks so much Dr. Susie, what I todayΒ  should go a very long way to open a page that will help other to help themselves

  • Ndawana Seibes

    I am having my intoduction to public health exam on Monday and this lecture is very helpful.

  • raheel ahmed


  • TALHA CH Altaf

    Yer mjy public health technology K bary ma batana K 2 year is j diploma ka kya benefit ha

  • Diallo Fatoumata Battouly

    It's a great presentation thank you

  • Roman KFM

    Public Health is a joke. I know plenty of latino and black HIV patients here in Ventura, CA getting treated like crap. They will stop helping teens and patients if Discrimination and prejudice evidence is shown. They really have nobody overlooking the malpractices of public health. Many kids are dying and spreading the disease because of the snobby workers at Public Health. Yet, they will excuse their lack of compassion or help to 'Not enough funds'.

  • ziad sapty

    You are magnificent

  • inam khan

    Wonderful explanation and wonderful reading only from lecture notes…this is not helpful at all

  • vpcreations n

    Great lecture. Thanks

  • Sakariye Cabdi

    It's very good lecture. Thank you Dr. Susie.

  • amit soni badshah alahabad

    thank you very very so much for your interesting information

  • Victor Chibueze Ijeoma

    Just coming across the very important lecture after more than 2 yrs of its release. Better late than never. I really appreciate it and want to thank all those who made it available for free particularly the CDC. This lecture has added a lot to my previous knowledge of Public Health and increased my desire to pursue a career in Global Health.


    Great course

  • Festo Mwebaze

    the core functions at the government levels need to be customized according to country structures… whereas USA has a federal type of government.. other countries like my own doesn't

  • zacs banda


  • RubeNuvo

    Maximum benefits for the largest number of people!

  • Sandesh Bhusal

    Really interesting and helpful for public health students and health professionals.

  • Nurul huda media

    great lecture

  • John Henry Ebere Okere

    Thanks very much for this educative and well detailed lecture.

  • Ibraahim Abdi Mohamed

    nic lecture

  • Monalisa Mohamed

    Good lecture ever i didnt watch lecture like this thnx alot


    Thank you for this wonderful lecture!

  • Alexandra


  • Chitravenkatesha Rao

    Very useful video. Thank you so much

  • Vanessa Flores

    Thank you! Learning , I start to read and study public health and I learned the meaning of public health with you Dr.! Blessings

  • karamba jawara

    Thanks fot the video. Am from The Gambia and am doing my Higher National Diploma on Public Health.

  • Daana Bekturganova

    was so useful and interesting for me, thank u so much

  • colaad yare65

    Thnk you so much madam

  • Dr:hassan Abdilaahi

    Public health my choose!

  • abdulrahman radwan

    Public health

  • Abdulrahman Radwan

    I like public health

  • James Tesloach

    Thank you so much dr i wonder that is gonna be good for our future

  • Mohamed Janneh

    I love it so very much

  • Sameh Ahmed

    very useful presentation

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